BBC HomeExplore the BBC
This page has been archived and is no longer updated. Find out more about page archiving.

24 September 2014

BBC Homepage

Local BBC Sites

Neighbouring Sites

Related BBC Sites


Contact Us

Features

You are in: Lancashire > Nature > Features > Ask the gardener: Pests and diseases

snail on a leaf

Ask the gardener: Pests and diseases

If your garden is over-run with creepy crawlies (eww!) Bill Blackledge can tell you how to get rid of 'em...

Warton's Bill Blackledge is one of the county's most popular and sought after gardeners.   If it's green and needs watering, Bill can tell you about it.  He has been answering BBC Radio Lancashire listeners' queries for over thirty years, which means he's been there nearly as long as the transmitter!

His knowledge is encyclopedic. After training at the under the then Ministry of Agriculture, Bill spent over twenty years at the Department of Biological and Environmental Services at Lancaster University.  Now, he's a regular course tutor at Alston Hall, Longridge and Lancaster Adult College.

For three decades, Bill has travelled the county with fellow judges as a regional judge for North West in Bloom.

So, whatever the problem, we like to think Bill can sort it out…… at least that's the theory!

------

Alan Phillips asks...

Our primroses flower heads are being pecked or removed by something eating the stems it would appear; ie the flower heads are left lying on the ground. Can you explain?

Bill replies...

Primroses do suffer from aphid damage and caterpillars Alan which mainly eat the leaves but have been known to damage the flower heads.  It would be worthwhile to check for slug and snail damage, but from the way you have described the damage to the flower heads it looks as though it could be birds which are pecking the flower.  I am sorry that I am not able to give you a concise answer.

------

Brian Whittle asks...

My Pyracantha leaves are covered with what seems to be a waxy coating with black spots under. The coating can be peeled back and the leaf under is dull. Can you suggest a cure? Thank you.

Bill replies...

Pyracantha Brian is prone to powdery mildew disease and this could be the covering on the leaves of your shrub.  They also suffer from Pyracantha Scab and also Fireblight which affects the flower heads.  I do feel that it would be worthwhile giving your plant a thorough spray with a fungicide such as Dithane or a systemic fungicide such as Systhane Fungus Fighter which will help to control the spread of powdery mildew and also scab.  You may have to spray more than once to keep the disease under control and to stop the spread onto new leaves.

------

Peter Bache asks...

I planted a Fatsia (24 inches tall) in the spring last year and for a few months it grew really well in its shady site. During August however, its smaller newly formed leaves were showing multitudes of pin holes which multiplied until the fleshy part of the leaves were eaten away, leaving just a skeleton. Since then strong new shoots have turned yellow and lifeless, and I have had to cut it back to older but healthier growth. Can you advise cause and treatment? This condition has also appeared on laurels close by, but they have not been so badly affected.

Bill replies...

You will find Peter that Fatsias and Laurels both suffer from shot hole disease which is a fungal disease and causes small brown spots to appear on the leaves and these spots are then replaced by small holes.  Unfortunately there is not cure for this disease but it is well worthwhile to ensure that both your Fatsia and Laurel receive plenty of feed, mulching and watering during dry periods.  You also say that the leaves are now in skeleton form which could have been caused by caterpillars and it is well worthwhile to check closely on the underside of the leaves for tiny caterpillars which can sometimes be difficult to see.  You will need during springtime to cut back your Fatsia to healthy shoots and providing that you keep your plant well fed I am sure that your Fatsia will recover.

------

Julia Veal asks...

My elderly father in law is having a lot of problems with codling moths. Last year his entire apple tree crop was full of the codling moth maggots. He tried a Pherome trap last year without success. What advice could you give him for this problem?

Bill replies...

I find Julia that using Pherome Traps is the most efficient method of controlling the Codling Month but, it is important that the traps are placed on the tree in sufficient time to catch the male moth before fertilisation of the female.  Codling Moths pupate during the winter months spending this time in bark crevices and in springtime the adult insects emerge and the female after mating with the male lay their eggs on leaves and young fruits.  The resulting caterpillars then burrow eating the inside of the fruit.  Pherome Traps work by giving off the same scent as the females and the male is therefore attracted into the trap where the sticky tape kills the males.  There are also insecticide sprays which can be used but is difficult to obtain full control with very large trees and timing of these sprays are critical.

------

Jane Hall asks...

I am creating a wildlife community garden. We have started a log-pile, in a shady corner, but I notice coral spot on some of the dead wood. Is it safe, or will it infect the nearby hedge?

Bill replies...

I am afraid Jane that your deadwood log pile is a breeding ground for Coral Spot and the air borne spores will infect living trees through broken branches, pruning cuts and damaged stems.  With regard to your hedge and other trees and shrubs which you may have in the garden I am afraid that it is a bad policy to leave dead wood and log piles in close vicinity.

------

Jason asks...

I have recently discovered fruiting bodies at the base of my paulownia tomentosa and after further investigation found that the roots are rotting at the base of the tree. I was too late to identify them as the recent frost and rain has turned them to mush. There were no bootlaces present in the surrounding soil but the wet spongy roots were coated in white mycelium. I cant find any literature that shows paulownia succombing to anything other than honey fungus but the fruiting bodies didn't seem to have collars on their stems. Any ideas? PS the crown is showing dieback and bacterial ooze is pouring from the bark at the base at the site of the fruiting bodies. I am worried as I was planning to plant 10 or so apple trees nearby.

Bill replies...

Paulownia Tomentosa is a magnificent tree Jason and well established trees produce beautiful spikes of mauve bell shaped flowers which stand above the giant leaves and I can therefore understand your concern regarding the rotting of the roots around the base of your tree.  The mycelium spores around the base of the tree is one of the symptoms of Honey Dew and I would again check underneath the bark at the base of the tree to see if there are any bootlace strands.  The die back of the crown and the bacterial ooze from the bark is a worry but again, like yourself it is difficult to say for certain whether this is has been caused by the Honey Dew fungi and I feel that it would be worthwhile obtaining a second opinion from a Tree Surgeon.  With regard to your ten apple trees I would personally refrain from planting until the cause of the problem with your tree has been determined.  Sorry that I cannot be of more help.

------

Jan Thurley asks...

I have had a honeysuckle for about three years, and every year it starts off beautifully with fresh healthy growth then later something completely strips the leaves off it. Also, the leaves on my box plants, which are in pots, are turning brown and have white/creamy tips.

Bill replies...

It sounds as though Jan the leaves on your Honeysuckle have been attacked by caterpillars which can quite easily decimate plants.  At the first sign of damage next year you will need to check the underside of the leaves to see if there are any small caterpillars present and then spray with an insecticide. Honeysuckles can also suffer from aphids but the damage caused will only cause the leaves to become distorted.  It may also be worthwhile to check and see if there are any slimy deposits because quite often you do find that snails eat the leaves of climbing Honeysuckle.  With regard to your Box Plants there is a fungal disease which does attack Box - causing the leaves to brown and the tips to go grey - but I am afraid that there is no product on the market to cure this disease.  If your Box Plants are situated in an exposed area the browning of the leaves could be wind scorch damage.

------

Mrs J Satterly asks...

We have a silver birch tree in our garden with rust stain running down trunk of tree, it has been like this a couple of months.  Please advise many thanks.

Bill replies...

One of the troublesome diseases of trees Mrs Satterly is bacterial canker which is a fungal disease that attacks cuts and abrasions in trees and the tell tale signs are amber brownish gum oozing from the infected areas and, this could be the cause of the rust stained material running down the trunk of your tree.  It would be worthwhile to obtain a second opinion from a local tree surgeon who will also be able to advise you on what steps you can take.

------

Shirley Burrows asks...

My pelagoniums have brown rust spots on the leaves, which then turn brown and shrivelled.  What can I use to treat it?, as I am worried they will die if not treated.

Bill replies...

If your Pelegoniums are suffering from rust Shirley you can spray with a general fungicide to keep the disease under control and a popular product is Dithane which is obtainable from most Garden Centres.  If you require a systemic fungicide I would suggest Systhane Fungus Fighter which is again obtainable from Garden Centres/DIY Stores.  Spray early morning or evening but not in direct sunlight as this will cause scorching of the leaves.

------

Jim Forteith asks...

My lawn is showing brown leaf-like fungi which I believe may be Lichen. I do not know how to treat. It has appeared in one lawn in sunny conditions and now appeared in a shady lawn.  Can you help? Thank you

Bill replies...

The leaf like lichens are quite a common occurrence on lawns which are badly drained and also in shady areas Jim and what you will need to do is to apply a moss killer to your lawn or lawn sand.  This needs to be applied approximately two to three ounces per ten square feet.  You will need to try and aerate your soil and I would also apply a general lawn fertiliser to give your lawn an added boast.  You also find that lichens appear if your soil is very acid and if this is the case a light dressing of lime can be very beneficial.

------

Darren Taylor asks...

The new vegetable shoots in our small patch are being destroyed by tiny slugs. We have copper tape all around and a couple of beer traps which deter the large slugs, but we cannot stop the small ones. Any ideas?

Bill replies...

The small grey slugs are certainly the troublesome ones Darren and what I find useful is to place pieces of black polythene or old pieces of sacking amongst your vegetable plants. When you turn these over the following morning you will find numerous slugs which you can disperse of.  You can use slug pellets providing that you can keep them away from the birds and wild life (hedgehogs/frogs) and you can do this by placing pellets under small pieces of corrugated sheets which the slug will be attracted to but the dead slugs will be out of reach of birds and wildlife.  You can also use this method with small plastic seed trays - raising the tray approximately half and inch from the soil surface - again the slugs can eat the pellets but will not be accessible to birds, etc.

------

Jinny asks...

We are overun with shrews and moles each year the hills and tunnels get more numerous and the garden is now sinking. Is there anything natural we can do as we are opposed to any killing methods. I did read about a mixture of fox and another predator mix to spread near the holes but this was an American site so not too sure it would apply. I would be very grateful for any help. The soil is heavy clay

Bill replies...

There are some unusual methods Jinny for trying to stop Moles in gardens.  One is to place mothballs down the holes and another is to place Holly leaves or other prickly leaves such as Berberiss down the run to make it uncomfortable for the Moles.  There is also the ultrasonic Mole Vibrator which when turned on gives out a high pitched noise which, again, will deter the Moles.  And, last but by no means least Moles do not like the scent of cats.

------

Catherine Blackburn asks...

My garden is infested with Vine Weevil! I have only just discovered what has been eating the leaves of all the rhododendrons, roses, shrubs etc having found a vine weevil and identified it. My rose leave are now turning yellow as well as having holes in them. My question is, how can I treat such a large area of infestation? It isn't simply confined to pots or to one area of the garden... the damage is very widespread. When and how should I start to tackle this problem? Many thanks in advance for any advice!

Bill replies...

Vine weevil is a problem pest Catherine and is very difficult to eradicate.  The adult vine weevil is nocturnal and tell tale signs of damage are serrated eaten leaves.  If you go out in your garden late evening with a torch you should be able to see the adult weevils on the leaves.  They are black in colour and are half to three quarters inch long and have pointed noses.  These need to be removed and destroyed.  The main problem is caused by the grubs of the vine weevil which borough into the soil and start eating the roots of plants.  There is a chemical insecticide on the market - Provado Vine Weevil Killer - which can be used as a drench to kill the grubs in the soil but is mainly used on plants grown in pots and containers.  There are also biological controls which, again, you wash into the soil and the tiny nematodes will start to eat the grubs of the vine weevil. These biological controls can be purchased through adverts in Gardening Magazines and also from Garden Centres.  It is a difficult problem to overcome and you will have to be diligent on keeping a watch for adult weevils and destroying any grubs you find in the soil.

------

Judith asks...

I have a large magnolia in my garden which has produced lovely white flowers each Spring before the leaves arrive. We have had this for over 40 years and it's never let us down. However, this year I notice that the seeds are going black and falling off. Also the leaves are full of holes and going brown on some of the branches. My husband reckons the leaves are being eaten by snails (lots of them about this year) but this wouldn't cause two different problems surely?

Also we seem to have two different types of seed heads - one which is long and thin with a serrated look and one which looks like an alien! I'm confused! Advice would be much appreciated.

Bill replies...

I would check the leaves on your Magnolia to see if they have been infested with caterpillars - caterpillars have been a problem this year Judith.  Your husband thought that the leaves had been attacked by snails and again this is quite possible but you would have noticed a slimy trail deposit left by the snails.  Regarding the 'alien' which is on your Magnolia this is a seed pod and due to warmer temperatures more Magnolias are producing these seed pods.  What you need to do is to wait until these seed pods are just beginning to split then remove from the tree and collect the seed. 

------

Sarah Bakewell asks...

I have 2 problems with my sufinia petunias, firstly they are covered in mildew, and secondly there are many leaves that are turning yellow and then withering and dying.
The plants are still flowering but the foliage looks extremely unsightly. Can you advise?

Bill replies...

With regard to the problems affecting your Sufinia Petunias Sarah I do not think that at this time of year (August) it is worthwhile spraying your plants with a fungicide to cure the mildew on the leaves.  This year has been a disastrous year for Petunias - they do not like moist damp conditions - and all over the country they are suffering from yellowing of the leaves and withering and dying.  I am afraid that it is impossible to improve the condition of your plants but, if we do have a late Indian summer it will be beneficial to your plants and all I would recommend is to apply a liquid feed at weekly intervals.

------

Ian asks...

I have a rose bush that is infested with both greenfly and ants, I know that ants have been known to farm aphids, but will either damage the rose bush? The ants have nested directly at the bottom of the stem. The rose bush is potted

Bill replies...

The ants Ian will protect the aphids from ladybirds and the sugary glucose which is secreted by the aphids is ideal food for the ants.  Regarding the ants nest if it is in the actual pot of the Rose Bush it will cause damage to the roots and I feel that they need to be removed.  The easiest method is to soak the whole pot in a large container of water which will drown the ants.  Once you have eradicated the ants nest you will find beneficial insects such as Ladybirds will return and keep the aphids under control and also small birds such as Blue Tits.  If you prefer to spray your Rose Bush to control the Aphids I would suggest that use one of the safer organic sprays which will not harm wild/bird life.

------

Heather Drewry asks...

I have an Acer. Which is outside. I have been told it has Mealy Bugs on it. I have used Provado Ultimate Bug Killer twice but it hasn't made any difference, if anything it seems worse. Is there anything else it could be instead? Or is there something else I could use to clear the problem up, as this plant has been with me for sometime and I don't want to lose it.

Bill replies...

Mealy Bug is problem pest Heather on a wide range of plants and you will find that in time Provado Ultimate Bug Killer will control the pest but what you do need to do is give your Acer a thorough spray with the insecticide and spray to run off.  The time to spray is early morning or late evening - do not spray during the day or in the midday sun as this will cause scorching of the leaves.  There are other insecticides which you can use such a Liquid Derris Plus - which is a natural insecticide - and also Spray Day Insecticide.  The important factor is whichever product you use you need to give your Acer a thorough spray to disturb the aphids which are enclosed in a cocoon.

------

Ray Sellars asks...

Our magnolia has started getting some sort of disease that leaves the leaves like skeletons. Do you know what could be causing this?

Bill replies...

I am certain Ray that the problem with the leaves on your Magnolia Tree has been caused by caterpillars and you will need to check the leaves to see are there are still caterpillars present.  Occasionally you will find that snails will climb up the main trunk of the Magnolia and these will also start eating the leaves.  Again, you will need to check the leaves for snails.

------

Theresa Sloyan asks...

We planted a young Laburnum tree this year. Its leaves seem to be eaten but I cannot see what is doing the damage. can you tell me what it is likely to be, and how to treat it.

Bill replies...

I have a Laburnum Tree in my garden Theresa and from time to time I do find snails have climbed up the main trunk and have started to eat the leaves and it is worthwhile checking your tree to see if snails are doing the damage.  The problems with slugs and snails has been problematic this year due to the very damp weather.  You need to keep a check on the leaves of your tree just to see if it is snail damage or damage by caterpillars and, to overcome the problem you can place a grease band around the tree which will deter the snails from climbing up and also there is available self adhesive copper tape which can be placed around the tree and which again will deter the snails.

------

Naomi asks...

I have recently started to grow herbs on my kitchen window sill indoors.  I have green chillis and bell peppers too.  I have noticed that they have terrible green fly, they seem to be really affecting the growth and health of the pepper and starting to do the same with the chillis which were growing really well.  What can I use for this that is safe? I plan to use the chillis and peppers to cook.

Bill replies...

Quite often Naomi Peppers become infected with Greenfly and with your Pepper being a food crop I am always reluctant to recommend insecticide sprays.  But, there are in the market safe insecticide sprays for use with food crops and one which is quite often used is Savona which, is a fatty soapy liquid, and when your spray it onto your Peppers the aphids become enclosed in the soapy liquid and suffocate.  You could also use a soapy liquid mixed with water and just wash this onto your plants and this will help to keep the aphids under control.  It is important however to give both your Peppers and Chillies a thorough washing before using. Please do remember to read all the instructions of any product you decide to use.

------

Rebecca MacFarlane asks...

One of my potted Acers turned black and died. On inspection, the soil in the pot is full of tiny jumping insects. Did these kill my tree? The insects can now be seen under the surface of the soil in my other pots how can I get rid of them before my other trees die? 

Bill replies...

I passed your question on to an eminent Entomologist at Lancaster University and he has stated:

"If these tiny jumping insects are springtails as I strongly suspect (not being able to think of anything else which would be tiny and jump, at least not without a fuller description) they are most unlikely to have been responsible for the death of the plant as they feed on fungal hyphae in the soil."

Following the above comments it is difficult to pinpoint what has caused your Acer to die back Rebecca - it could be waterlogging of the soil which quite often happens if you use a peat base compost.

------

George Smith asks...

There is mottled umber moth on my pear tree what can I use to get rid of it?

Bill replies...

The mottled Umber Moths are usually seen on wing during October/November time with last sightings being seen late April.  They fly at night and you often seen them resting on trees during the day light hours. Eggs of the Umber Moth hatch out in March and the larvea/caterpillers of the moth feed on the leaves of a wide range of trees and ornamental fruit trees until the late May time.  Regarding the solitary moth you have seen on your Pear Tree George I would not worry too much but I would suggest that you keep an eye out for caterpillars.

------

Angela Dawson asks...

I have two orange plants, I noticed the other day a damaged looking orange on closer inspection there was a green grub inside the orange. What is this and how can I treat the plant?

Bill replies...

I passed your question on to an eminent Entomologist at Lancaster University and he has stated:

"Without seeing a specimen it is impossible to say what it is.  If there is only one fruit showing signs of damage I would say no treatment is necessary and if there is only one grub per fruit again I would suggest leaving nature to take its course.  An externally applied contact insecticide would have no effect on an insect larvae already inside the fruit and a systemic insecticide would probably render the fruit unfit for human consumption whether it killed the insect or not."

------

Susan Patnell asks...

I have lillies in pots and they have started to get little red beetle like flies on them. How can l get rid of them?

Bill replies...

Your Lillies Susan have been infected by the Lilly Beetle which, is a 'beautiful' red beetle but is certainly a problem pest for Lilies.  Until recently the only cure was by going out daily and collect the beetles from the plant and destroying them and I found the easiest way of collecting the beetles was by using small jar and brushing the beetles into the jar with a small paint brush.  There is however now on the market an insecticide spray - Provado Ultimate Bug Killer - which will control Lilly Beetle. You will need to read the instructions carefully before use.

------

Matthew Kolakowski asks...

Our privet hedge has started to die in sections. It seems to have some sort of infestation of very small green insects that cluster underneath the leaves. The leaves are now starting to wither, curl and die. The worst effected part is underneath an Acacia tree. Please can you help us rescue it!

Bill replies...

To control the insects Matthew you will need to spray your infected hedge with a general systemic insecticide which can be obtained from Garden Centres and DIY Stores.  You will need to spray early morning or late evening to avoid leaf scorch - which can occur if you spray midday during sunny weather.

------

Letty Scott asks...

I have a lonicera - about two three years old and was flourishing until recently when leaves are falling, particularly in the middle area. What should I do?

Bill replies...

I would check your plant Letty for aphids and also the rust disease as your Lonicera (Honeysuckle) is prone to both, and both the aphids and especially the rust disease can cause leaf drop. If aphids are present you can spray with a general contact insecticide and if rust postules are present - which can appear on both the underside and upperside of the leaf - again you will need to spray with a recommend fungicide such as Dithane.  You will also find that Honeysuckles prefer to be in a slightly shady spot - they are a woodland plant.

------

Michelle Aston asks...

I have an acer the stems are covered in what looks like mini legless woodlice! They are different sizes and slighlty different colours. Apart from this it seems healthy?

Bill replies...

It looks Michelle as though your Acer has been infected with a scale insect and I would spray the stems with an insecticide spray and the one I would recommend is Provado Ultimate Bug Killer.  You will need to spray early morning or late evening - try to avoid spraying in direct sunlight which can cause leaf scorch.

------

Karl Green asks...

How do I stop squirrels eating the new buds on my acer pseudoplatanus?

Bill replies...

I am afraid that there is not easy answer to your question Karl. N matter how you try to protect your trees the squirrel will find a way of getting to the new buds and I am afraid the only way to protect your trees is by trapping the squirrels and I would contact the Pest Control Department within your Local Authority regarding traps and how to disperse of the squirrels.  I am afraid that you are not allowed to set squirrels free in the countryside.

------

Sheila Revel asks...

I have a four year old acer which is covered in black fly. I have never had this before and it is affecting the new growth of leaves. Why has problem suddenly occured?

Bill replies...

Black Fly has been a problem this year Sheila and I am afraid that you are going to have to spray with an insecticide to control the problem.  If you require an organic insecticide I would use Organic Pest Control or another natural insecticide product is Bio Liquid Derris Plus.  Do not spray in direct sunlight  - I would advise spraying early morning or late evening.

------

Nigel Maitland asks...

We have a Magnolia Stellata which has been in our garden for three years. This year the tree which is now 5' tall is covered all over with a grey green growth on all its joints, the growths look a bit like a moss but are hard and crusty.The tree is still covered with white flowers but no sign of leaves yet. How can we get rid of it and will it damage the tree? Our soil is very sandy and free draining. We would appreciate some help. Thank you.

Bill replies...

The moss algal/lichens growth has been quite common on a wide range of trees this year Nigel and this has been caused partly by this year's mild winter.  This can also happen if trees are situated in a very shady and damp position and I have seen this happen quite often to mature Magnolia Stellatas.  Regarding treatment I am afraid there is no chemical available at the present time but, you will find that during the summer months the moss lichen growth will start to shrivel and can be easily peeled off.

------

Pauline Beevers asks...

Rabbits have made a burrow in my garden which is next to a field.  What is the best way discourage them and how do I get rid of the burrow?

Bill replies...

I feel that to overcome the problem long term Pauline you are going to have to erect a rabbit proof fence.  You can use one inch galvanised chicken mesh wire which needs to be approximately three feet high but also needs to be one foot below the soil surface.  This is quite an expensive operation but is the most reliable rabbit proof method.  There are products on the market - such as Renardine (which is made from animal waste products and comes in a liquid form) - you soak old rags in the product and place around the garden and it is the scent given off by the Renardine which is reputed to keep the rabbits away.

------

Dave Brown asks...

I have bought a Gardenia Kimberley Jasmine plant from a garden centre which is kept indoors, and have recently noticed that some white millipedes have appeared around the base. What is the best method of removing them, please?

Bill replies...

I am worried that the white Grubs Dave could be the grubs of the Vine Weevil or the grubs of the Sciarid Fly and you will need to check if these grubs are in the soil.  The tell tale signs if it is Sciarid Fly is that if you knock the plant tiny little black midges will appear from soil level and from under the leaves. If it is Vine Weevil there will be white pinkish grubs in the soil.  There is a product on the market which will kill both grubs and this is Provado Vine Weevil Systemic Insecticide.

------

David Bright asks...

My laurel hedge seems to being eaten by something as there are a lot of chunks out of the leaves. The hedge looks good aprt from this.

Bill replies...

It is difficult David to pinpoint which pest is causing damage to your Laurel Hedge but, there is a good chance it could be the adult Vine Weevil.  The tell tale signs are there - chunks and notches eaten out of the leaves - and the Vine Weevil attacks a wide range of shrubs such as Camellias, Laurels and Rhododendron and the Weevil is approximately half an inch long, has a pointed nose and is black in colour and they are nocturnal which means that you will have to go out late in the evening with a torch to see them.  If you do see them you can catch them in your hand and disperse of them.

------

Richard Brown asks...

I have a camelia and I have just noticed that the leaves are turning very black and there are what looks like small brown insects on opposite side of leaf?

Bill replies...

Camellias can suffer from scale insect damage Richard and this could quite easily be the problem with your Camellia plant.  The scale insects can be found on the underside of the leaves and the insects secrete a sugary glucose which attracts ants and also on which a black fungi grows causing the leaves to go very sticky and black in colour - this is commonly known as Sooty Mould.  You can spray the insects with an insecticide spray and the one I would recommend is Provado Ultimate Bug Killer. I would recommend spraying early morning or late evening and avoid spraying in direct sunlight.

------

Elaine Price asks...

My ornamental maples, fig tree and ornamental plum have developed light green/ greyish patches on the tunks and stems. Some of these have tiny black dots within them, others have progressed to a bright yellow fungus type growth. What can this be and can it be treated?

Bill replies...

Due to the very warm and damp humid conditions we have had this winter Elaine there has been a vast increase in alga and lichen growth on the stems and trunks of a wide range of ornamental trees and, unfortunately, there is no chemicals on the market at the present time which you can use but you will find that during the summer months these green/grey patches will shrivel up.

------

Lisa asks...

We have just bought a new house that has a beautiful pear tree that fans the entrance. We know the tree is circ 150 years old and looks as though it is not very well.  The trunk and branches have a greenish /white and black covering.  It did produce a lot of fruit in the summer, but most of it was not fit to eat, we were told it was diseased.
Please can you advise what to do, I am a complete novice!

Bill replies...

It is very difficult to say exactly what problems and diseases your old Pear Tree is suffering from Lisa.  The green and black covering on the stems and branches is probably alga and fungal growth which often affects old fruit trees and this should shrivel up during the summer months.  You say that last summer the pears were diseased and unfit to eat and this could quite easily be Pear Scab which can drastically deform the fruit.  There is a fungal spray which you can to use to keep Scab under control but, again, the difficulty is that your Pear Tree will be very large and you will need specialised equipment to completely spray the tree and you would need a spray programme i.e. regular spraying two/three times over the growing period.  With it being a very old tree I feel it would be advisable to contact a Tree Surgeon to see if your tree needs pruning and requires attention.

------

Katie Halls asks...

On the citrus trees in the garden, there seems to be a combination of two pests, one white and woolly under the leaves which has attracted ants, so I'm wondering if it is aphids also something that seems to be leaving a ziggy zaggy line on the leaves and they are curling, any suggestions?

Bill replies...

You are correct in saying that we are dealing with two pests Katie.  The white woolly pest could either be woolly aphids which secretes a waxy coating which protects the aphids from predators but, these aphids usually congregate around the stems and young shoots.  The other pest could be the Mealy Aphid - these aphids have a waxy like coating and usually appear on the under side of the leaf. Both of these aphids will secrete a sugary glucose substance which will attract ants.  The ziggy zaggy lines on the leaves of your Citrus plants will have been caused by Leaf Minor and the grubs of these insects burrow into the leaf and feed on the leaf tissue and this is what caused the zig zag affect and if you look closely you will be able to see the tiny grubs and these can be squashed between finger and thumb.  Because we are dealing with a food crop I am always reluctant to recommend an insecticide spray but there are contact safer insecticides available which contain a fatty soapy liquid which can be used on food crops but, you will need to read the instructions carefully.  These will keep the aphids under control but will not kill the Lead Minor Grubs and if may be better for you to just remove the affected leaves.

------

Martin asks...

I have a young prunus nigra in the garden which seems to be doing well but this year some of the small branches are covered with a green thin fungus/lichen that extends and wraps along the twigs, smothering the buds as it does so. The underside of the fungus/lichen is white and if you take some time you can sort of unwrap it from the twigs, though that is harder to do when it is around small buds. Is this serious and if so what should I do?

Bill replies...

Moist damp conditions are ideal for algal growth and lichens, especially if the trees are growing in a shaded spot.  Unfortunately there is not much that you can do to control the spread except to continue with what you have been doing.  During the summer months the alga growth and the lichens will tend to shrivel up.

------

Mrs T Tyldesley asks...

I laid a complete new turf lawn in November, which started to die back within weeks. I have today been told by the supplier that it has leatherjackets, I have checked and found at least 6 leatherjackets in a 12 inch lenghth of turf I have 44 m2.  He has said that he will replace the turf, but will I not end up with the same problem in 6 weeks time even if I pick them out? The soil underneath is so waterlogged that I will not find every one. Also what about the new plants I have already purchased and want to put in, it is a start from fresh project after building work. The supplier has insisted that he wants to know tonight what I want to do.  HELP.

Bill replies...

Leatherjackets are the larva of the Crane Fly/Daddy Longlegs Mrs Tyldesley and the Crane Fly lays its eggs in the lawn during early autumn time and when the eggs hatch the leatherjackets burrow into the turf and start feeding on the roots.  With reference to your problem I feel that it is important that your infested turf is removed from your garden as soon as possible and as you say your soil is waterlogged you will find that the leatherjackets will come to the soil surface and these can be removed by hand or the birds will eat them.  I am sure that your supplier will have treated any new turf to kill the leatherjackets but, it is worth checking the new turf to check if there are any leatherjackets visible.  Regarding the new plants that you have purchased leatherjackets usually feed on the roots of turf but have been known to eat the roots of small plants.

------

Ron asks...

We have two box hedge trees, one either side of our front door.  One is lovely but the other one is going bare in the middle and seams to be dying off.  The tree is about 3ft high.  It looked like it had little cobwebs over the part that has now got no leaves and the little stems look dead.  What can I do to restore the tree and what do you think happened to it?

Bill replies...

There are a number of fungal disease which are now causing damage to Box Hedges Ron - dieback is occurring in the shoots and stems and as far as I am aware there is no immediate cure but you are recommended to feed your hedge Spring and Summer time to encourage new shoots to appear.

------

Les Sims asks...

We laid new turf in a garden in October 2006. The turf died within 6 weeks, our suppliers now say that leatherjackets have caused this and they are spraying their fields now (February). Can you advise as I didn't think this is the time of year to deal with leatherjackets. Is it possible for these to kill 300 sq metres of turf?

Bill replies...

It is impossible for me to say without seeing your turf that is has died due to the infestation of Leatherjackets Les but, it must have been a very heavy infestation to kill your turf within a 6 week period.  If you have the same problem again you will need to peel back some of the turf to see how many Leatherjackets are feeding on the roots.  Regarding spraying there is a spray which can only be used by the commercial sector and this will be the one that your suppliers are using.  For the amateur gardener there is a new product on the market called Provado Lawn Grub Killer which will control Chafer Grubs and Leatherjackets but this is best applied August/September/October time when the grubs are very small.

------

Robert Blackwood asks...

I have Japanese Acer, it's about 5 yrs old. Has been doing well but last season developed an orange fungus on one of branches. This I cut out but now is at base of plant and one root is covered. My local garden nursery suggested applying surgical spirit to the affected area. This worked briefly but has come back with a vegeance. Is this fungi scale? From RHS description I read it does not appear to be. No mention of orange. The next problem is the wood then dies. It's a small beautiful tree and I would hate it to die. Also what is best feed for Acer? Thank you

Bill replies...

It is difficult to pinpoint exactly what the fungal disease can be Robert but one of the most common diseases, which attacks a wide range of shrubs, is the Honey Fungus (Armillaria) and the symptoms are a white fungal growth appears near the bark at ground level, and on the roots are strands of fungi which are black and are similar to boot laces, and in the Autumn time amber coloured toad stools appear around the base.  The other disease which caused die back of branches is Coral Spot where you will find raised pink spots on the branches.  You can also get die back of the branches if your Acer is growing in very badly drained soil.  With regard to feeding your plant I would use a general base fertiliser sprinkled around the base of the Acer in early Springtime - Fish Blood and Bone Meal or GrowMore are good established products to use.  With your infected Acer you will need to cut out any diseased branches and stems.

------

Steve asks...

I have an apple tree and the trunk and limbs are green and the apples have maggots in what can I do to cure this problem?

Bill replies...

It is quite common for Apple Trees especially it they are growing in a shady spot to have algal growth on the trunk and stems.  This algal is caused by very wet and damp weather conditions and I would not worry about it Steve it is just a natural occurrence.  On the question of maggots in your apples it could quite easily be the grubs of the Codling Moth or the grubs of the Apple Saw Fly and you will need to spray your tree with a contact insecticide early June and repeat again three weeks later.  You can also control Codling Moth with a Pheromone Trap which will attract the male Codling Moths. When inside the trap the moths will get stuck to the sticky glue preventing them from fertilising the females.

------

Katie Cordell asks...

We have a lilac which we planted this summer as quite a mature tree. It doesn't seem to have any mushroom type growths at its base, but the top leaves are withering and the lower leaves are covered in a white fungal layer. We'd like to use an organic spray if possible, is there one you recommend?

Bill replies...

A number of Lilacs have suffered this year Katie due to the very high sustained temperatures during June/July and August this year, and with your newly planted mature tree I am sure this is the main reason why the leaves have withered and dropped off.  On the question of white fungi on the leaves it is far too late to spray now (December) but to avoid infection next year when the leaves have all fallen they will need to be collected and disposed of.

------

Jo Edwards asks...

We have a lemon tree, that's about 5ft tall, its not bearing fruit, but the leaves are very strong in citrus smell, it's doing really well but we keep finding little larva wrapped in a silk like substance that curl the sides of two leaves together. We have never seen any sign of a beetle/moth/insect and are totally baffled to what they are. Hope you can help, thanks.

Bill replies...

The pest you have described Jo is Mealy Bug and it is quite a common pest of citrus trees. The silky fluffy substance that you describe protects the Mealy Bug from predators and both the adults and young extract sap from the plants.  Clusters of these pests are often found on the stems and leaves axles and also on the underside of the leaves.  If you only have one or two clusters the easiest method would be to wash these clusters off with a damp soapy cloth rather than spraying with an insecticide spray.

------

Tony Edgley asks...

Can I treat polypore fungus at the base of my large Beech tree or should it be cut down?

Bill replies...

Many thanks for your question Tony but I am sorry to have to inform you that I am not aware of any method or any chemicals available to treat Polypore Fungus on the base of your Beech Tree.  With regard to whether you should cut your Beech tree down I would contact your Local Authority or a Tree Surgeon for on the spot advice.  Your Local Authority will advise you if there is a Tree Preservation Order on your tree and also if the tree needs to be cut down.

------

Debbie Candy asks...

Please help! My Bay Tree has black power on the underside of the leaves (I think it is some sort of insect) I tried cleaning it of with soapy water but it came back two weeks later. Can you help?

Bill replies...

Your Bay Tree is suffering from sooty mould Debbie and the sooty mould is caused by scale insects which live on the underside of your Bay leaves.  The scale insects secrete a glucose substance on which these sooty mould grows.  Washing with a soapy liquid will keep the mould under control but will not kill the scale insects.  If you are growing your Bay Tree for ornamental purposes you can spray your tree with a systemic insecticide and the one I would recommend is Provado Ulimate Bug Killer.  It is however important that if you do spray you will not be able to use the leaves for culinary purposes.

------

Stephen asks...

I have a plum tree growing in my garden, and have had a large crop of fruit this year.  However a large number of mushrooms have grown on the tree over the last month or so.  What does this mean and how do I get rid of them?  Any advice would be appreciated

Bill replies...

The toadstool/mushrooms growing at the base of your Plum Tree Stephen are the fruiting bodies and these produce spores which are then dispersed and form fine spider like strands which are called Mycelium - this is the vegetated part of the fungi which lives on decayed matter - dead tree stumps and roots - and it is the Mycelium which produces the toadstools/mushrooms.  To stop the toadstools/mushrooms spreading you will need to remove them by hand before they disperse the spores. The fungi which gardeners' fear most is the Honey Dew Fungi (Boot Lace Fungi) and they will feed on live roots and can seriously damage trees.  The toadstools are amber in colour.  If your require any further information please email me again at BBC Radio Lancashire.

------

Bev Cordier asks...

I have large holly bushes in my front yard. They are covered in a white powdery substance and are withering away. Any ideas?

Bill replies...

The white substance Bev on the leaves on your Holly Bush is powdery mildew which is an airborne fungal disease and to keep it under control you need to spray the leaves which a fungicide.  I would use a systemic fungicide such as Systhane Fungus Fighter which you will need to spray until it runs off.

------

Barry Cuff asks...

I have a very large willow tree and at the base of the trunk where the bark has eroded there are quite a few large holes that some type of insect has caused. Should I spray insecticide over the affected area? Any suggestions to save the tree would be appreciated.

Bill replies...

What I would do Barry is when your Willow Tree is completely dormant spray the trunk of your tree with a tar oil winter wash which will control both pests and predators. Also, to minimise the risk of infection from bacterial canker it would be worthwhile to fill in the holes with a plastic/bituman filler.

------

Janet Henderson asks...

I had a hydrangea in a pot for about four years and the other day while tidying outside the plant just lifted off the soil, it had no roots at all. When I checked the pot I found white grubs, can you tell me what they are and how to get rid of them as they seem to have eaten all the roots in the pot.

Bill replies...

I am quite certain that the grubs which have eaten the roots off your hydrangea Janet are the Vine Weevil grubs.  It is a troublesome pest and first and foremost you must disperse of the grubs and soil and give your pot a good clean.  You will need to check the other pots you have in your garden and I would recommend the you water the pots with the systemic insecticide Provado which will kill any Vine Weevil grubs which are in the soil.  There is also a biological control for the Vine Wevil grubs called Nemys H which can be obtained through Garden Centres and Gardening Magazines.  There is also a potting compost that you can use which contains a chemical which will kill the grubs as they enter the soil and I would suggest that you use this compost if you do a lot of container gardening.  Again, this can be obtained from Garden Centres.

------

Steph Robinson asks...

A friend was listening to your programme on Tuesday evening and just caught the end of you explaining about the disease the rhododendrons had been effected with at Rivington Pike. Would you please give the the information again as I have quite a few and would like to know what to look for and the treatment that can use or what to do if it strikes. I've also been told that it is airborne and it can be passed to oak trees which I also have. Thank you very much.

Bill replies...

The disease in question is caused by the fungi Phytophera Ramuram.  The spores are airbourne and the fear is the disease maybe passed onto our native Oaks.  I  personally am not familiar with the disease Steph but, there is extensive information about the disease on the DEFRA Website - giving details of the symptoms and who to notify.

------

Heather McNiven asks...

My raspberries have been smothered with Shield bugs this year and apparently they are due to hibernate soon. Can I erradicate them before they go to roost! What will kill them as they do spoil the crop and I had about 10 per fruit stem.

Bill replies...

There are quite a number of different species of Shield Bugs Heather.  The main common garden species is the plain green Shield Bug and although they are not renowned for causing a great deal of damage they do suck sap from the leaves. They are however beneficial to the gardener as they also eat aphids and other garden pests but, in your case, with there being substantial amounts of the Shield Bugs on your Raspberries they will do damage to the leaves by sucking the sap.  I do not think they will harm the fruit but if you have any damage to the fruit this could quite easily have been caused by the larvae of the Raspberry Beetle.  If you need to use an insecticide spray to kill the Shield Bugs I would recommend Spray Day.

------

John Jones asks...

Are the lilac trees dying off through a new disease? Mine are suffering badly now.

Bill replies...

I am not aware of any new disease which are attacking Lilac John but Lilacs are prone to Honey Dew Fungi (Boot Lace Fungi) and it would be worthwhile checking around the base of your tree for any amber coloured toadstools which is one of the symptoms of Honey Dew Fungi.  It is also worth taking into account this year's extremely high summer temperatures which have caused die back to quite a number of trees/shrubs including Lilac. What you will need to do is to cut back any dead/diseased branches and next Spring apply a liberal dressing of a general base fertiliser and, if possible, I would also mulch with well rotted manure.

------

Johanna Duke asks...

I have ten pyracantha shrubs and three are covered with a white mildew substance/fungus?  It started on one and has in the past couple of weeks spread to the other two.  Can you tell me what to do or identify this fungus?

Bill replies...

The white mildew on your Pyrachantha shrubs Johanna is powdery mildew which is an air borne fungi disease and, to keep this under control you will need to spray your shrubs with a fungicide and the two which I would recommend are Dithane 945 and Fungus Fighter - both of which will control a wide range of diseases including powdery mildew.  You will need to spray your shrubs thoroughly to run off.

------

Dave Armstrong asks...

I have a number of gooseberry bushes and the leaves have been eaten away from the edge to the stem  - what is responsible for this? Can't be slugs or snail, the stems are too prickly.

Bill replies...

The main pest of Gooseberries Dave is Gooseberry Saw Fly and the caterpillars of the Saw Fly can devastate the leaves of the Gooseberry Tree in a very short period of time.  The first group of caterpillars will appear on your Gooseberries early May time but with this year's very hot summer the Saw Fly has produced three to four batches and I am sure it is the Saw Fly Caterpillars which are now damaging you Bushes.  To keep the caterpillars under control you need to spray your bushes with an insecticide such as Spray Day - which will kill aphids, black fly and also caterpillars.

------

Olly asks...

How do I stop cats from coming in my garden and fouling my soil?

Bill replies...

There are some weird and wonderful methods of trying to deter cats from gardens.  One method is to fill cordial bottles with water and place around your garden.  When the large tom cat comes into your garden it sees it reflection in the bottles and scarpers.

The high-tech method is to buy a 'sonic cat repellent machine' which can either be plugged into mains or battery operated and, when the cats go anywhere near the machine it gives off a very high frequency sound which scares the cats away.  There are also aromatic plant oil granules - which you scatter around your garden soil, and the pungent smell given out from granules is reputed to keep cats at bay.  Renardine is another very popular product and contains a mixture of animal waste materials - it comes in a liquid form - soak in rags and place around the garden, and this again gives out a very pungent animal smell which deters cats.

------

Denyse Gregson asks...

For the last three years I have had scab on apples and pears. The pears being particularly bad. Please advise what to use and when.

Bill replies...

Scab is a serious disease in both apples and pears - the leaves become mottled with brown spots - the fruit becomes badly scarred and disfigured and, it can also affect the shoots and stems.  To keep scab under control you need to spray at regular intervals through the spring and summer months with a fungicide spray.  Do not spray your trees when they are flowering as, this will affect pollination by the bees.  The fungicide which I use is Dithane.  This is contact fungicide which I find very effective.  I also would recommend during the autumn and winter months to rake up fallen leaves which will contain infected spores - these need to be dispersed of.

During the autumn and winter months spray the trees with a funicide to kill any harbouring spores.

------

Norman Hough asks...

I have some patches of black stuff growing on my lawn, what is it and how do I get rid of it?

Bill replies...

The 'black stuff' on your lawn is almost certainly the black algal growth which you find on lawns which are poorly airated and badly drained.  You can easily remove the algal growth by watering your lawn with a moss killer or alternatively dressing with lawn sand which containers ferrus sulphate (watering within two days of application will be needed to avoid scorching).  Spiking your lawn in the spring and autumn will also help to aerate the soil and keep down the algal growth and regular feeding and top dressing your lawn will also beneficial

------

Brian Rowe asks...

I have just moved house and there are a number of apple trees in the garden. One has a scab on every leaf. Can you tell me should I remove all the leaves now or should I wait until after the summer?

Bill replies...

I feel it would be worthwhile Brian to spray the infected apple tree with a recommended fungicide to control the scab.  A good safe contact fungicide is Dithane.  Spraying your infected tree will help to stop the spread of the disease to your other apple trees.  I would also next year work out a spraying programme for all your apple trees to ensure that the disease is kept under control.  This briefly entails spraying the trees approximately every three/four weeks during the early Spring/Summer time.  During the Winter months it would be advisable to collect all the leaves off the trees and burn them.

------

Eileen Sandham asks...

I started a compost bin a year ago when we tried to take some compost out there are millions of ants - how do I get rid of them?

Bill replies...

With so many active ants around your compost bin Eileen it could well be that you have an ants' nest in your compost bin or in close proximity and, it may be worthwhile to remove the rest of the compost from the bin to check if indeed there is a nest there. Destroying the ants nest will obviously irradicate your problem.  If you cannot find a nest I would carry on using the Nippon Powder but, I would mix the powder with sugar - ants will then carry this mixture down to the nest to feed the queen and if you can actually kill the queen the nest will cease to function.

------

Anne Joyner asks...

We have a couple of acres of garden in the country but have a big problem with rabbits.  They eat all the new shoots and often dig for the roots.  Is there any pest control I could use to deter the rabbits or is there anything I can plant around the shrubs that the rabbits hate the smell of?

Bill replies...

The most successful Anne would be a rabbit proof fence.  The fence would need to be approximately four foot high and the wire mesh needs to be approximately one to two inches in diameter.  You will need a five foot roll because you will need to bury six inches of the wire at least below soil level to stop the rabbits burrowing underneath.  I realise this method is going to be very expensive to fence the whole two acres of your garden but I feel it would be worthwhile to fence at least part of your garden where you have your herbacious plants/vegetable plot and shrubs of significant value.
You mention other methods and there is a product on the market called Renardine which comes in a liquid form - made from animal waste products - and has a pungent smell.  It is the actual smell which keeps the rabbits at bay. You will need to soak old rags in the Renardine and place the rags around your trees and shrubs.

------

Y Wilkinson asks...

My father has a very high amount of wood pigeons in his garden and area, and he wonders if there is anything he can do to make them relocate elsewhere? He is 81, very ill, and their constant cooing and messing on mum's clean washing is upsetting him. Do any of the sonic bird scarers work for wood pigeons please? Many thanks.

Bill replies...

The best method for keeping the wood pigeons at bay is going to be the sonic bird scarers.  The man-made scare crows tend to work for only a short period of time before the wood pigeons become accustomed to them.  Some gardeners have placed plastic replicas of birds of prey on their gardens and they say they have been very effective at keeping the pigeons at bay.
I hope that your father gets well soon.

------

I Calvo asks...

Please can you tell me how I can get rid of moles in my garden?

Bill replies...

There are some weird and wonderful methods of getting rid of moles in your garden.  One method is to place moth balls below soil level along the runs - the idea being that the smell would deter the moles.  There is also the sonic mole deterrent which makes a high pitch sound which the moles dislike and another old method is to place prickly leaves such as Berberris and Holly again along the runs with the object of deterring the moles.  Last, but by no means least, there are the mole traps which I 'still think' can be purchased from Hardware Stores or farmers' auction marts and, it may be worthwhile if there are any farms in close proximity to have a word with the farmer who may be able to help you.

------

Katheryne Sparey asks...

Can you please tell me how to get rid of worms which are in the compost from my indoor plants.  They got infected by being beside a plant that had been outside for a while.

Bill replies...

I feel the easiest method would be Katheryne to gently knock your indoor plants out of the pots and remove any worms that will be around the side of the soil and also in the pot.  Worms are a beneficial creature to the garden and I am reluctant to advise the use of an insecticide as a soil drench and I am sure if you carry out the above process a couple of times you should be able to disperse the worms.

------

Mel asks...

How can I stop crows from digging worms up from my lawn and making holes in it?

Bill replies...

Over the summer months the most effective method is to use the high tech bird scarer which makes a piercing humming noise.  I find the man-made scarecrows seem to be only affective for only a very short period and you finish up with the crows perching on the head and arms!

If your lawn is also being frequented with other birds such as starlings you may have problems with soil borne pests such a Leather Jackets or Chafer Grubs and to overcome this problem it is well worthwhile to apply a dressing of top lawn in autumn.  This will help to keep the grubs under control.

------

Marie Blower asks...

My red robin, which is in a large pot, has lost most of its leaves and has green powder on the stem. Bone meal was added to the pot about a week before. Could this have caused the problems and can I save my tree? Thank you.

Bill replies...

It happens quite often with Photinias (Red Robin) that if the plant dries out or, they suffer a check in growth Marie they do tend to drop their leaves, and I feel it would be worthwhile to prune some

------

Ian Lever asks...

I've got white fluffy growths on my apple tree, what are they?

Bill replies...

I am quite sure that the growths on your apple tree have been caused by woolly aphids.  What happens Ian is the numerous aphids secrete a white waxy coating to protect them from predators.  They do not cause a tremendous amount of damage to the tree but if you are worried you can spray with a general contact insecticide. I find the easiest method is to wash the growths off with a hose pipe.

------

Jane Hook asks...

What can I do about rose chafer beetles? My white iceberg roses are infested although the red flowered climber next to it hasn't any sign of infestation.

Bill replies...

The two types of Chafer Beetle which could be infecting your Iceberg Jane - one is the Cock Chafer which is a large reddish beetle and this beetle will eat the leaves of your rose and the other is the smaller Rose Chafer Beetle which tends to eat the petals of the rose.  The most affective control method is to go out once or twice a day and pick off the beetles and destroy them.  You could spray with a general contacting insecticide but there is always a chance that spraying will damage the flowers.  If you do spray - spray early morning or in the evening and not in direct sunlight.

------

Margaret Bostok asks...

My daughter has found her containers and baskets from winter time are infested with cockchafers. How can she destroy them so she plant summer plants now? She has no grass at all.

Bill replies...

The cockchafer grubs in your daughter's hanging baskets and containers Margaret will eat the roots of a wide range of plants - the grubs can grow up to two and a half inches long - they are white in colour with three pairs of legs and a brown head - the bodies are shaped like the letter C.  If your daughter does not want to kill the grubs I feel the best method for disposal would be to place all the grubs from the baskets and containers into a large bin bag and dispense of it.

------

Bob Whiting asks...

Two weeks ago I planted tomato plants in a prepared plot and some of the leaves at the top are begining to turn white. What is the cause? Someone said it might be blight. Would the replacements be better grown in large tubs or is blight an airborne fungus? If it is I'll make up a cover for them.

Bill replies...

The white powder on your leaves is mildew and it is not often you see mildew on the leaves of tomatoes so early in the year.  I would dispose of the plants and start afresh. I would also personally grow tomatoes in tubs in a multipurpose compost but I would be inclined to leave planting for a couple of weeks until the weather gets warmer - especially if you're planting outdoors.

------

Anne asks...

Could you please identify the growths on my azalea, I cut them of last year and sprayed them, but they are back.

Bill replies...

The Azalea Gall is a common disease in Azaleas causing the leaves to distort into small galls and swellings - which can also occur on the stems.  If you look closely Anne you can sometimes see the white powder on the galls which is the fungal spores and is not easy to control using a fungicide spray and I find the best method is to cut out the infected leaves and shoots.

------

Margaret Wordley asks...

My Clematis is being eaten by black ants, any suggestions please?

Bill replies...

I usually find that ants do not do a large amount of damage to plants Margaret.  But they love feeding on honeydew which has been secreted by aphids and I feel your Clematis will have been infested with aphids which in turn, will have secreted the sweet honeydew glucose which the ants have been feeding on.  You will need to spray your Clematis with a general insecticide spray - which not only will kill the ants - but also any aphids.  To avoid leaf scorch please spray your Clematis early morning or evening - not in direct sunlight.

------

Erica Haddon asks...

My lawn suffers each year from leatherjacket larvae. April/May time for about two weeks the crows shred the lawn and it looks like mini bombs have gone off. It all happens between sunrise and 6am. Any suggestions gratefully received.

Bill replies...

I would like to start answering your question by giving you some tips on how to control the Leatherjackets in your lawn.  The Leatherjacket is the larva of the Crane Fly (Daddy Long Legs) and the Crane Fly lays its eggs in late summer in the lawn - the grubs hatch out in the Autumn time and the will eat the roots of your grass throughout the Winter/Spring/early Summer - causing your grass to have swards of yellow patches.  It is important that you try and control the Leatherjackets in the early stages.  You can water your lawn in the Autumn with an insecticide or you can treat your lawn - again in the Autumn - with Autumn Top Lawn which, contains Carbaryl.  You will need to continue each year with this treatment to keep the pests under control and, this will cut down the food chain for the Crows.

------

Janet Caine asks...

One of my beautiful phormiums in a pot has mildewy white powder at the base of the leaves, which I know may be phormium Mealy Bug. I've read that it's hard to treat as the bugs are tightly packed in the dense base leaves. Is my plant doomed?

Bill replies...

Mealy Bug is not any easy pest to control and you are going to have to spray your Phormium Janet with a systematic insecticide and the one I would recommend is Provado Ultimate Bug Killer.  The insecticide kills a wide range of pests including Mealy Bug and you will need to give your plant a thorough spray. It will kill the pests by contact and also part of the insecticide is absorbed into the plant leaf system and this will ensure that the deep seated Mealy Bugs and Scale Insects are controlled.  You may need to repeat the spraying in approximately two/three weeks time and I would spray your plant either early morning or late evening.  Do not spray in direct sunlight as this could quite easily scorch the leaves.

------

Joanne Young asks...

I have a Bay Tree in my garden and the trunk has what looks like white mould on it.  Is this something that can be treated?

Bill replies...

The most problematic pests of the Bay Tree Joanne are scale insects and the insects secrete a glucose substance on which a grey fungal mould grows and this could be the mould which is on the stem of your Bay Tree.  If the trunk of your tree is not too large I would be inclined to wash of the mould with a fatty soapy liquid (Savona) which can be purchased from Garden Centres/DIY Stores.

------

Terry Taylor asks...

I have got a lot of ants on my fruit trees, could you tell me what is the best product to get rid of them please?

Bill replies...

I am always reluctant to recommend insecticides to control pests on edible crops Terry but there are organic sprays available which contain natural fatty acids which are safe to use and can be used on edible crops right up to harvest.  If you decide to use one of the organic sprays  I would recommend spraying your fruit trees early morning or late evening to avoid leaf scorch.

------

David Jackson asks...

Why do my apples (French Golden Delicious) come out with scarred skins?

Bill replies...

I am sure your Golden Delicious David is suffering from Apple Scab Disease which not only discolours the fruit but also the leaves. The disease is very problematic in hot and humid conditions.  The most effective method of controlling the disease is by using a spray programme starting early Spring when the leaves are just beginning to appear and you will need to spray at regular intervals until late June/early July, but you must not spray when your trees are flowering as this will affect pollination by the bees.  I feel it is too late this year to start spraying but it is important to collect all the leaves when they drop in the Autumn and and burn them. 

------

David Underwood asks...

How do I get rid of moles in my garden?

Bill replies...

There are many unusual methods of deterring moles from your garden David and quite a number are based on moles being very sensitive to noise and smell.  You can buy a Mole Sensor Deterrent - battery operated - which will give off a high pitch piercing sound when inserted in the mole hill and switched on.  These are quite expensive and a cheaper method is to place a couple of children's plastic windmills along the mole run and these will also give off high pitched sounds in windy weather.  Placing moth balls down the mole runs again is used to deter the animals and also soaking pieces of old rags in greasy oil and again placing these down the mole runs is supposed to be effective.  An old country method is to place prickly leaves of brambles/holly and rose clippings vertically down the run to act as a deterrent.  What you have is basically the equivalent to a barbed-wire fence.  The most effective method which some people object to using is mole traps - which can be purchased from hardware stores.

------

Terry Jenkins asks...

l have a privet hedge which is very slowly dying, small sections each year, leaves turning brown, started to water twice a week, to no affect, privet is quite old. The rest is very healthy all though there is ivy in the middle, could this be the problem, please advise.  Thanks.

Bill replies...

A common soil borne disease which effect Privet Terry is Armillaria Root Rot (Honey Fungi).  The roots are attacked by boot lace black fungi strands which spread and grow through the soil causing sections of the Privet Hedge to die back steadily, and it could quite well be that your Privet Hedge is suffering from this disease.  Visual effects could well be amber coloured toad stools growing around the soil of your affected Privet Hedge and if you peel back the bark at base level again in the infected area you will see fungi strands.  It is a very difficult disease to control but I would advise you to remove any dead Privet shoots and branches.  On the question of the Ivy which is in the middle of your Hedge it would be very advisable to cut this back and if possible remove it.

------

Sue Eaton asks...

My Acer and Magnolia Susan outdoors have a white glue-like substance on them with disc shaped creatures stuck to it. I looked up mealy bug and I'm not sure if it is this as they are outside. I blasted them off with the hosepipe and the white stuff like marshmallows was all stuck to the fence. These are not on the leaves but on the branches and trunks. What could it be please? My magnolia is 15 years old and never ailed a thing although we moved to this garden two years ago and I brought most of my shrubs with me. Please give me the benefit of your experience.

Bill replies...

What you are going to have to do Sue is to spray your plant to run off with a systemic insecticide and the one I would use is Provado Ultimate Bug Killer which will kill scale insects and also mealy bug. I would spray your trees early morning or late evening and if it is a bad infestation you will probably need to spray more than once and as explained above you will need to spray to run off using a powerful jet.

------

Kate asks...

We have just moved into a new house with three plum tress. Most of the fruit is infested with small maggots. What can I do about this problem for next year?

Bill replies...

A serious pest of the Plums Kate is Plum Sawfly and the tell tale signs are a tiny hole in the Plum which is surrounded by a sticky glucose substance and inside the Plum is a creamy white grub which is the grub of the Plum Sawfly, and I am sure that this is the grub you are having problems with. What you will have to do next year is to spray your Plum Trees approximately seven to ten days after petal fall - using a contact insecticide and hopefully the insecticide will kill the emerging grubs of the Sawfly before they have chance to enter the young plums.  For this year it is important that you collect any infected plums and disperse of them.

------

R Walsh asks...

I have two pots with pelagoniums in them in one of the pots the leaves are full of holes but I cannot find anything on them can you advise please?

Bill replies...

There are two pests which could be the cause of your problem.  One is the flea beetle which eats small holes in the upper surface of the leaf and there is also a wide range of moth and butterfly caterpillars which will eat holes in your Pelagoniums.  Many of the caterpillars are nocturnal feeders which is why you will never see them during the day.  Dusting your plants with an insecticide dust will help to keep the flea beetle/caterpillars under control and also spraying your plants with Spray Day will help to control the pests.

------

Sally Turner asks...

How do I get rid of ants on my small bird of paradise? There are no aphids and the plant does not have blossoms yet so I'm not sure what is drawing them!

Bill replies...

Like yourself Sally I am slightly mystified as to why there are numerous ants on your Bird of Paradise Plant if there are no aphids present and your plant is not in flower. As you will be aware aphids secrete sugary glucose which ants love and the flower of the Bird of Paradise secretes masses of nectar - which again the ants love to eat.  It is very unusual but it would be worthwhile to knock your Bird of Paradise out of its pot to see if there are ants in the soil.  If there are numerous ants in the soil I would think that there would be a small ants nest inside the pot.  If this is the case you will need a large container full of water and immerse your pot in the container  this will drown all the ants. It may also be worthwhile to dust around the soil of the pot with a recommended ant killer dust - one which contains permethrin.

------

Christine Edwards asks...

I am finding small bright red beetles on my lilies which have been in containers for a few years without a problem. Help please!

Bill replies...

The red beetle on your lilies Christine is the Lilly Beetle which is fast becoming the most troublesome pest for lilies.  Until recently the only method of control was to go out daily and remove by hand the beetles but there is now an insecticide on the market -  brand name Provado Ultimate Bug Killer - which kills a wide range of pests including Lilly Beetle for up to a period of eight weeks. I personally have never used this product but the control of Lilly Beetle is listed by the company among the pests.

------

Terry Griffiths asks...

I have a victoria plum tree which has done well this year, I do have some saw fly infestation, but not as bad as previous years due to me hanging up a trap to catch the male fly, the problem I have is the fruit is going bad on the tree and withers away, they have a purplish bloom on the plum I recognise this as the plums that are going to rot, can you please tell me what your thoughts are on this problem.

Bill replies...

It sounds as though your Plums Terry have been infected with Brown Rot which is a fungal disease. The fungi can gain entry through wounds in the fruit ie. birds pecking and Sawfly holes and the spores of the fungal disease can be easily spread by birds, rain splash and insects and the plums deteriorate very quickly and become shrivelled.  You need to remove the infected fruit to stop the infectious spores and you will also need to remove any fruit which as dropped on the floor.

------

Jo Wollington asks...

I recently grew peas in a container but they become covered in a very fine, grey powder.  I have now harvested the whole crop and pulled the plants out to take to the garden waste tip.  Could you tell me what was wrong with the plants?  Also how do I use the harvested peas to produce seedlings for next year?  Many thanks.

Bill replies...

Your peas have been infected with powdery mildew Jo which is an airborne fungal disease.  It covers all the plant with a fine grey powder and can decimate a crop very quickly.  The weather conditions this year have been ideal for the spread of the disease and with it being a food crop it is very difficult to control using fungicides and not many can control the disease.  The disease is very dominant during the summer months and  it may be worthwhile to try and grow a more early crop of peas next year.  On the question of keeping peas for seedlings next year I would be slightly wary - taking into account the problems with the powdery mildew

------

D. England asks...

How do I get rid of caterpillars eating my home grown cabbage?

Bill replies...

The problem with caterpillars on cabbages is that we are dealing with a pest on a food crop and I am always reluctant to recommend using insecticides.  However, there are contact insecticides which can be used but you will need to read very carefully the instructions in regard to what type of food crops they can be used on.  Sometimes the easiest method - which is quite tedious - is to go out daily and remove the caterpillars by hand.

------

Stephen McGowan asks...

I have a Kilmarnock Willow planted in the back garden and recently the leaves have started to develop bright yellow/orange spots with what looks like powder underneath the leaves. Do you have any idea what this could be and is there anything I can do to stop this ? I have looked online to try and identify this but with no success.

Bill replies...

Your Kilmarnock Willow Stephen has been infected with rust - an airborne fungi disease which, as you describe causes yellow orange spots/postules on the leaves.  You can spray the leaves with a fungal spray such as Dithane or Systhane Fungus Fighter which will help to keep the disease in check.  You will also need to ensure that when the tree has shed all its leaves the these are removed and destroyed.  It would also be worthwhile during the winter months to spray the stem and branches and also the soil around the tree with a fungal spray to kill any harbouring spores.

------

Brian Dawkins and Robert Macinnell ask...

How do you treat ants nests on lawns without damaging the grass?

Bill replies...

I sympathise with both of you with your problems with ants nests on your lawns and unfortunately there is not simple answer to your problem, and this years dry summer has only increased the problem.  To try and cure your problems you need to irradicate the ants nests which are underneath your lawns and to do this you will need to kill the queen ant whose job is to continuously lay ants eggs within the nest.  The ants you see scurrying on the lawn are the working ants and they take back food to the nest to feed the queen.  If you check where the working ants are coming out of the holes in the lawn and place in this area a mixture of Nipping Ant Powder and sugar the ants will take this mixture down to the nest and feed the queen and hopefully in time the nippon/sugar mixture will kill the queen stopping the egg production and the ants nests. I would also carry on using a general ants dust/insecticide to keep on top of the working ants.

------

Mary Clay asks...

I have a yeodensis ornamental cherry that only got planted a few monts ago and is around 6-8 ft high. It is bleeding sap in various places up the truck and on some branches. What is wrong with it and what can be done?

Bill replies...

If there is orange gluey liquid oozing from the trunk and branches Mary the symptom is synonymous with bacterial canker - which is an air borne fungal disease which enters Cherry Trees through damaged branches and wounds in the tree.  The other disease which your tree could be suffering from is Gummosis which is a physical disorder which causes patches of gluey gum to appear on the surface of the branches and trunk and both Cherry and Plum trees are very susceptible.  You do need to check your tree carefully Mary and if the gluey substance is appearing from damaged branches if could well be canker and you will need to cut out the infected areas and treat the wounds with Aborex.  If there is just patches of glue gum on healthy stems and shoots it could well be Gummosis for which there is no specific cure but applying a good general base fertiliser in early will help to improve the vigour of the tree.

------

Anne Armitage asks...

We have a large blue spruce next to our driveway and it continually drips sap on to the cars, it is hard to remove and is damaging the paintwork, can you tell me why it has started to do this, its been happening for most of the summer.

Bill replies...

It could well be Spruce Aphids that are causing the problem. The aphids secrete honey dew and it could quite well be that it is the honey dew droplets which are dripping onto your car.  Another cause could be if one or more of the branches on your tree has been infected with bacteria canker. The orange gluey substance caused by the bacteria canker could be secreting from infected branches and again dropping onto your car.  The Blue Spruce is a lovely tree and I feel it would be worthwhile to contact a Tree Surgeon or your Local Authority to check your tree out.

------

Trudi asks...

My potted (grafted) minature willow is being eaten alive by tiny grubs! They have devoured all of the lower leaves and are now moving up the tree. Now even the uneaten leaves are looking very sorry for themselves. The bugs look like little caterpillars. Help!

Bill replies...

It is tiny caterpillars which are doing the damage Trudi to your Willow and you will need to spray your Willow with an insecticide spray.  The one I use is Sprayday Greenfly Killer Plus - which kills a wide range of aphids and also caterpillars.  You will need to give your Willow a complete spray to run off.  Although your Willow at the moment looks 'worse for wear' it will recover.

------

Ann Watt asks...

I purchased a Fatsia Japonica two years ago as a little foot high shrub but now its grown to about 5-6 foot high. It was very healthy until last week when it appears to have been ravaged by some kind of bug that's eating all the leaves. I have inspected the leaves at various times of the day and can't see any larvae etc...  What should I do to stop this?

Bill replies...

If the damage Ann has occurred over a short period of time it looks very much that the problem pest is caterpillars.  Some of the species of caterpillars are nocturnal and just feed in the evening and this is probably the reason why you have not seen any.  If just the edge of the leaves have been eaten away it could also have been caused by the adult Vine Weevils but, if as you say, there has been substantial damage caused it does point towards caterpillars.  What you need to do is to dust the leaves of your plant with an insecticide dust or you can use an insecticide spray such as Sprayday.  It may also be worthwhile to go out in the evening with a torch to see if you can see any caterpillars. The adult vine weevil is approximately half an inch long - black in colour - and has a pointed nose.  If the leaves of the plant have been badly damaged you can prune your Fatsia Japonica back in the Spring time and it will produce young shoots again.

last updated: 14/05/2008 at 11:45
created: 20/10/2006

You are in: Lancashire > Nature > Features > Ask the gardener: Pests and diseases



About the BBC | Help | Terms of Use | Privacy & Cookies Policy