Definitely one of our most frequent questions is ‘should ivy be removed from trees’. We are happy to have ivy as positive part of our ecosystem.
Autumn-flowering, it is a vital source of late-season nectar for invertebrates and
pollinators, as well as a winter nutrition source for birds and other hungry wildlife. It offers
safe harbour for many creatures, including one species of invertebrate here on the Common
that is on the rare and endangered red book list. Ivy is not parasitic – it obtains its nutrition
from the ground, not from its host tree.
The danger that ivy does present is when its weight and mass increase the ‘sail area’ of the
tree, making it more prone to being blown over in winter storms; particularly where ground
may be waterlogged or where the tree’s vigour is reduced for any reason, limiting its ability
to compete with the ivy.
Our conservation team follows London Borough of Richmond upon Thames policy; we recognise ivy’s important role in providing habitat and nutrition for pollinators, invertebrates and birds. We aim to manage sympathetically the balance between tree vigour/safety and the vital role ivy plays within our ecosystem.
A site assessment in January 2017 identified trees of potential concern that would benefit greatly from the ‘banding’ of ivy from base to approx. 1.5m on trunks, along with clearing around the base of these trees. This creates a much-needed clear view of tell-tale signs of concern such as:
- fungal fruiting near the base (a sign of rot in the root system)
- ground heave (when the tree starts to move and the soil cannot hold firm)
- ‘bark inclusions’ where a tree has multiple and the damp in the fork can lead to fungal attack
This treatment also reduces the sail area (once the ivy dies back) and lessens associated risks. Therefore, our existing policy is to clear from good specimen trees and those near to paths and roads, whilst leaving more than enough habitat. We also clear from trees thought to be at risk, in order to check trunks periodically. As with much of our conservation work, this will not be carried out in
one fell swoop, but gradually as part of our three to five-year plan, working within the seasons which will cause least disruption.
Banner image: Ivy bee enjoying late-season succour from ivy flowers. Photo credit: Penny Smallshire