Report on Arboriculture Talk

Arboriculture
A talk by Mike Turner, Royal Parks Arboricultural Manager
April 26th 2012

Arbor is Latin for tree and Culture means to care for and grow.

Seven years ago each Park had its own manager for trees, now a team of 4 oversee all the Royal Parks, the gardens of 10 and 11 Downing Street, Canning Green and Poets’ Green: in total 2035 hectares of parkland and 13 Km of the Longford River. 485 are woodland with 150,000 trees of which 1500 are veteran trees. To put this in perspective, the London tree population is 8 million giving an average of 38 trees per hectare. Bushy Park has 32 trees per hectare but Richmond Park has 88 per hectare.

Trees have many benefits; they have landscape value, reduce the risk of flash flooding, reduce noise, provide shade, provide a habitat for wildlife and reduce air pollution.

There has been a review of street trees by the London Assembly. Assessment is based on 4 variables: basic value based on size (trunk area, nursery prices, planting costs); functional value; adjusted value (location, amenity value, appropriateness); full value or life expectancy.

Sensors on trees in the Parks have shown a 4degree lower temperature than outside the Parks. Also the trees help reflect heat from the ground.

Priorities for inspections in Bushy Park are the main paths, roads and hotspots followed by areas where the public pass through but do not linger. Less busy areas and those with no or restricted access have lower priority. Approx. 90% of Bushy Park has been inspected with the addition of an aerial view.

Where trees are damaged, sound sensors are used to check the extent of the decay. It is possible to allow fungal growth and still keep the tree. The current legal framework protects all wild birds, nest, bats etc. Most small holes where branches may have broken off or been removed are bat roosts.

Veteran tress have a higher biodiversity value but require more care and can also be dangerous. Each tree has an individual management plan with a total score indicating the effort needed to conserve it.

Unfortunately there are new pests and diseases such as Oak Processionary Moth, Massaria (a fungus on London planes), Bleeding Canker, Leaf Miner, acute Oak decline.

You may well see some of us with binoculars inspecting Oak trees during June and July.

Report by Jane Cliff