Sheena Patterson of Oxford Garden Design sees the trees from the woods

There’s not much I wouldn’t do for my daughters including, it seems, swinging through trees like Jane chasing Tarzan.

Last weekend found our tribe participating in the Go Ape experience, which involves climbing up trees to dizzying heights and descending on long zip wires whilst admiring the views. This is not something I’d normally recommend for a woman of my age but as it was a birthday treat for daughter number two I was literally dragged along and banned from spectating.

I confess to being a bit of a tree hugger so at 18 metres off the ground, I got this strange feeling of how small I am, but also how in touch I was with the environment. It almost goes without saying that having strong, healthy trees is all-important at the Go Ape sites.

Protecting them is of paramount importance, and an environmental impact assessment is an essential part of the planning application for every site.

Arborists use sonic imaging to ensure trees are sound enough to support the activities and softwood protectors are put around trees before cables are wound around them.

From my lofty position, as far as my eyes could see, all the trees looked in perfect health making it all the more poignant that I know that the scene could be dramatically different in 10 years’ time.

Plant pests and diseases were hot topics at this year’s RHS Chelsea Flower Show, which featured displays that aimed to raise awareness about the UK’s biosecurity and susceptibility to imported problems. Ecologists warn that ash dieback is now unstoppable and that Britain’s ash trees are doomed. Their demise also threatens hundreds of insects, mosses, lichens and birds. Gloomy news indeed. It will take several years for the disease to spread. Some trees will fight back for a while but will eventually succumb.

Reflecting on this from my tree top position, it wasn’t hard to see the impact this is going to have.

Just as Dutch elm disease devastated the landscape in the mid-70s, once again our trees are under threat. Horse chestnuts have been hit by two life-threatening diseases. The first is bleeding canker: bacteria infects the bark, cutting off the water supply to the crown. The other involves a relatively new pest to the UK: the leaf-mining moth, originally from the Balkans.

Aside from the obvious problem of children being deprived of illicit games of conkers in school playgrounds, it’s hard to imagine a landscape without horse chestnuts.

Drastic action might help. A killer disease affecting larch and sweet chestnuts appears to have been eradicated in the Forest of Dean after 100,000 trees were felled in 2012, since then there have been no new reports of the disease in that area.

The nice young man who helped to strap me into a tight, life-saving, harness at Go Ape, assured me that they take their responsibility to the environment very seriously.

Apparently they work with specialists to ensure that the tree top antics of middle aged women and their like have minimum impact on the forest and an annual health inspection takes place at every site.

So although the trees of Britain are under threat, it is comforting to know that there are plenty of people willing to take action and make a difference.