The "Handbook for Phase 1 Habitat Survey" describes woodland as an area where the vegetation is dominated by trees more than five metres high when mature forming a distinct, although sometimes open, canopy.
Woodlands are amongst our most complex and diverse habitat systems and there is no such thing as typical woodland (my observation!). Many factors influence what a particular woodland will be like and what wildlife one might find there. The influences that readily come to my mind are (in no particular order if significance):
- The type of tree that forms the canopy; broad-leaf deciduous trees, evergreen conifers or a mix of the two
- The density of the trees and how close together they are; whether there are clearings, glades and rides between them
- The foundation soil underlying the woodland; variations between acid/alkaline and dry/wet soil can produce significant differences
- The area covered by the woodland; larger woodlands are likely (but not necessarily) to be more diverse
- The age of the woodland; obviously older woods will have more mature trees than a recent plantation
- The management of the woodland; this plays a major role and may be harvesting for timber, coppicing for hurdles, cover for pheasant rearing and so on
A woodland typically has three layers:
- The canopy formed by the upper branches of the trees
- The under-storey formed by shrubs that can grow and prosper in shade under the canopy
- The floor which is profoundly affected by the amount of light reaching it through the canopy and the leaf mix that falls from the trees
Put all this together and you quickly see why woodlands can be so diverse; there are so many factors at work. In simple terms though there are five main types of woodland you might encounter in Dorset. I have described each in this section, click/tap the images below for more information about them:
- Broad-leaf: a woodland where the canopy is formed almost exclusively by deciduous broad-leaf trees like ash and oak
- Acid: a woodland where the acid soil means that the tree mix is often oak, birch and possibly some Scots pine
- Wet; a woodland where the floor is almost continuously wet, often with standing water, where alder. poplar and willows dominate
- Mixed: a woodland where conifers have been planted amongst deciduous trees, often pines amongst beech
- Plantation: a woodland almost exclusively pine or spruce planted for a timber crop
Walk into any woodland and look at the main trees present and you can easily decide which of these environments you are in. Each is quite distinctive and has a unique feel and a unique flora and fauna. Look for evidence of the trees being in straight rows, this indicates a recent plantation.
There are no 'natural' woodlands in Dorset but there are some that are classified as ancient and these tend to be where the wildlife is most diverse and well established.