Up near the huge Wishing tree I noticed a very old and very dead rotting tree trunk. I rubbed my hands together in glee, anticipating the sheer number of mini ecosystems we might be able to keep our eye on for the next twelve months. And sure enough, this week we noticed lots and lots of spider webs and a few holes: some large, made by wood peckers and some small made by wood boring insects.
First let me introduce you to the second, albeit dead, tree we will be studying over the coming year:
You can see A7 by the Wishing Tree at the back, and B4 standing next to the dead tree.
The following photo shows the dead tree, taken from the Wishing Tree side:
And a final one with my gorgeous B4 (sorry, can’t help myself!):
The Importance of Deadwood
Dead and decaying wood is incredibly important, whether it is found within living trees, standing dead trees, or dead wood lying on the floor. It is the perfect environment for a variety of insect colonies which in turn provide food for bats and birds.
Decaying wood offers a huge number of constantly changing microhabitats. Because of this, deadwood is always left intact and untouched to allow colonisation to occur as swiftly as possible. Veteran trees (of which there are many in the woodlands we are studying) provide most of the decaying wood. Much of the decay happens inside the ring of living sap wood where fungi works to decay the inner deadwood whilst preserving the outer living wood. Far from damaging the tree, inner decay causes a hollowing out, creating trees which are often more stable than non-hollow ones. The goal of the conservators is therefore to keep the veteran tree alive for as long as possible, to encourage this sort of decay.
However, this tree is looong dead and the first thing we noticed is that the trunk is covered with moss and has many holes drilled into it:
You can probably see in the background one of the many holes we found in the trunk. I took a photo of a couple of the other ones because you can clearly see they have been hammered away by the beak of a bird, very probably one of the many woodpeckers which reside here:
In the last photo above you may be able to see some of the insect holes we found. It is the insect populations in deadwood which are so important as they feed those higher up in the food chain.
The other thing we noticed was the spider webs. I had no idea there was such a variety of webs. In fact the only type the deadwood didn’t have was the common ‘orb’ web. We found one which seemed to be a mishmash of web threads:
Some that seemed to create shelves within the giant holes of the deadwood:
The ones which fascinated me the most though were the webs which seemed to create their own tunnel:
Aren’t they beautiful? Of course, when we returned home I needed to look up the different types of webs that spiders weave. There are four main ones, three of which we had found just in our tree:
And here they are from the deadwood trunk:
The next time we study this deadwood I will be encouraging the children to carry out some research into how the local conservators are taking part in a veteranisation process. But that’s a nature study for another day.