The importance of providing food for wildlife.

I have always felt that gardeners should be working to support nature in the garden wherever possible. So providing food for wildlife especially in town gardens is a really positive thing.
Just by using a small tree like the Hawthorn, Crataegus monogyna you can easily combine great aethetic pleasure with a really useful source of food for the local bird population - or indeed humans if you want to go through the labour of cooking up some Haw Sauce!