What does a tree surgeon do? Jon Hammerton is most at home scampering up and down trees, but what does his job actually involve, and what advice can he offer for gardeners? Jon answers our questions below.

How Jon climbs trees

In this exclusive clip, he takes us through how he climbs trees, the equipment he uses and how he gets up to the top.

Q. What are you checking for when you're climbing around in the trees?

Dead wood, splits and cracked limbs - limbs that will split out under heavy snow, rain or wind. So we look to reduce them - taking end-weight out to prevent the tree from dropping these limbs. We also do crown-liftings where we take the bottom branches off so you can see under and it stops the crowns touching the ground.

Q. What else does your job involve?

Every part of my job is to do with the trees from the roots to what goes on at the top. Each season has different jobs - in winter, we remove trees and wood that we've lost in the summer and mill the timber. In summer, we tidy the trees up by thinning and dead-wooding, and strengthening trees with cables and bolts. If trees aren't looked after from a very early age, things that haven't been done become problems when they mature. Here at Kew we like people to see the trees as they are, and as they would be in their native situation.

Q. What kind of work do you do at root level?

Getting the ground conditions right for the tree is very important. We have a lot of compaction at Kew - the trees' feeder roots live in the top 20 to 25cm (8-10in) of the soil and have been getting trampled over many years, compacting the soil and starving the trees of nutrients, air and water. We use a de-compaction machine to loosen the soil around the tree so the roots can get what they need.

We also clear away the grass which can take away moisture from the tree when it rains, and encourage the gardeners to blow leaves under the trees when they fall to create natural, organic mulch which traps moisture and encourages worm activity.

Watch Tony’s exclusive tips on mulching.

Q. Is arboriculture all about tools or do you use other solutions to help you with your work?

We innoculate the trees with Mycorrhizal, which is friendly fungi that helps the tree to become more adaptable to harsh weather conditions, and at the same time prevents it from being infected by aggressive fungi. In a woodland situation, there would be a natural fungal balance but in an artificial environment like Kew we need to create one through inoculation and mulching with organic matter. You can use Mycorrhizal at home but it doesn't like artificial fertilisers, so be careful when you’re feeding your tree or neighbouring plants.

Q. How can I look after my trees at home without calling the professionals in?

If you're planting new trees, make sure that you buy a tree that will fit your garden. Formative pruning is important at a young age - prune the tree to the shape that you want it as soon as possible using secateurs, which are better than using a handsaw, but using a handsaw now is better than using a chainsaw 50 years on.

Watch Tony’s exclusive tips on pruning.

Q. What health and safety precautions should I take at home?

Don't take on anything that you can't do. You shouldn't be working off ladders - it's dangerous. Anything above what you can reach you should be bringing a professional in. Use the right and best equipment. There are good amateur and professional handsaws available and trees love them - but wear gloves and goggles when you're using a saw. Take your time - don’t rush - and get advice if you’re not sure.

Q. Who should I contact if I need help?

Before you start any major work on an established tree in a garden check with the local authorities, to see whether it has a Tree Preservation Order on it, or whether you're in a Conservation Area. If it has, you'll need to apply for permission to have the TPO lifted, which you can get through your local planning department. Always seek advice from a professional company that has been recommended. You contact your local authority or the Arboricultural Association who can recommend a registered or approved contractor in your area.

Q. How do I get rid of rogue samplings, for example: sycamores?

Dig them up as small as possible, don’t wait for them to get big and don't cut them.

Q. What can I do with trees, roots and branches that have been removed?

Try to shred it, and then compost it, don't burn it. Compost the chips or use them as a mulch. Use any logs to build a stag beetle bank - it doesn't have to be big like the one we have at Kew, and you can help to preserve the stag beetle population.

Q. Do tree houses damage trees?

Many tree houses today that are professionally built aren't attached to the tree, and therefore allow room for growth. Using nails and clamps to attach a tree house will restrict the growth and movement of the tree and create problems later on in the tree's life.

Q. When is it safe to let children play in trees?

It's a serious issue; you can't get intimate with a tree unless you climb it and cuddle it. If a child feels comfortable climbing a tree, let them do so - with the appropriate supervision of course!

Video clip - Jon in action

Here's a clip from the series where Jon climbs down the inside of an elm tree.