This week has been national tree week: the annual celebration of trees and a marker of the beginning of the tree planting season. I will admit that although I know the trees at Flatford are integral to the garden's wildlife value, I don't think about them as much as I should - probably because they largely get on with the business of being trees, without much help from myself and my colleagues! This week has been a great opportunity to reflect on their importance.
The tree that stands out for me is the large silver birch that stands opposite the entrance. Planted a good fifty or so years ago, this tree is now mature as Silver Birch are a fast growing pioneer species (one that colonises bare or disturbed habitats). The birch is an ideal tree for us to have in this position, as it has quite an open canopy and so allows some light to filter to the plants below it. This layered habitat of canopy and understory can support a diverse array of organisms, and the birch itself supports a large number of specifically adapted and generalist invertebrates.
From my casual observations, it is the alders that have been drawing the most attention from the birds at Flatford this week. Alder are in the same botanical family as the silver birch, but are happiest in moist soil and hence they grow in the area between the garden and the river. Alder trees are familiar to many, as they have catkins and the seeds are formed inside a structure reminiscent of a small pine cone. It's these that have been the focus of the birds' attention with goldfinches, siskins and blue tits all twirling acrobatically as they seek out their seedy meal.
There are lots more interesting trees at Flatford, each with their own story to tell. They really have the power to define the place in which they exist, and be very beautiful at the same time.
If you're looking for something to do over the next couple of weekends, but don't have the space to plant a new tree, think about nest boxes. It's reckoned that the best time to put up new boxes is in the autumn, as this gives local birds a good opportunity to check them out before the breeding season kicks off. There's loads of information on making and siting nest boxes on the RSPB website.