Saturday, 17 January 2015

Looking after the health of our trees

Ruby and I have been going around the whole site doing the tree health survey this week. It's a process that takes a couple of days, but as we are a site that has relatively few trees this is quite quick! We walk all the popular routes and busy areas of the property, eying up all the trees, looking for any potential dangers. We will be working on a few small actions arising from the survey over the next few weeks.

One tree was leaking sap from a wound
This interesting willow has lots of good nooks and crannies which makes great habitats for bats and insects
The first action we've taken was to reduce the height of the old hollow willow out the front of the visitor center. We were sad to have to take such drastic action on this iconic tree, lots of the staff and volunteers are very fond of it, but it was starting to become unsafe. All the new healthy growth was on the top of the tree, supported by a slowly rotting trunk, and with it being so close to a main path we didn't want it to crack and fall over the path.

The lovely looking but rather precarious old willow
We borrowed a large chainsaw form Anglesey Abbey and John got to work on Friday morning. He reduced the height in stages, taking the weight off the top slowly, stopping the whole tree splitting longways down the middle while he was doing the work. As he was cutting we realised just how rotted the tree was as the saw passed through parts of it like butter.

 John was able to push his hand through parts of the wood where brown rot had taken hold. Brown rot is one of the common methods of wood decaying. A fungus attacks the cellulose in the wood, leaving behind the lignin which creates part of the structure of the water transport system in the tree, the xylem vessels. As this drys out it gets a characteristic cubic appearance and the brown colour which gives this type of rot its name.

The finished job.

 The willow is still home to lots of creatures, a confused lesser stag beetle was found emerging from the trunk this morning, the sunshine fooling him into thinking it was spring already. We also found this fella as we were chopping the tree, giving Ruby a fright as he was the size of a tennis ball!

A rather hansom spider