Flowers of deciduous woodlands
The pleasure we gain from a deciduous wood owes much to the myriads of smaller plants which gain a footing wherever they can. The flowering plants and ferns occupy the ‘field’ layer, below that mosses and fungi predominate, and the trunks and larger limbs of trees are colonized by mosses, lichens, liverworts and fungi.
To appreciate the whole range in this community, it is necessary to visit a given wood at different times of the year. The greatest diversity ofusually occurs in spring and early summer. In spring many flowering plants, such as primroses, wood sorrel and wood anemones, seize the twin advantages of rising temperatures (guaranteeing that there are insects abroad to pollinate them) and a still leafless tree canopy to admit ample sunlight. As the canopy develops overhead a dappled shadow engulfs the woodland floor and a second generation of more shade-resistant herbage flourishes, dominated in the southern lowland oakwoods by a green carpet of dog’s mercury. Other more colourful inheritors of the shady floor are bugle, ground ivy and bluebell. The particular blend of flowering plants is conditioned partly by type (whether it is acid or alkali), the density of the canopy and the kind of trees and leaf litter around. Thus, in some damp northern ashwoods on limestone soils, the field layer is dominated in summer by ramsons, giant bellflower and yellow archangel.
Summer is also the high season for ferns which thrive well in the still, moist conditions found in the woodland interior. Best known is bracken, which flourishes in shade. In spring its uncurling downy fiddleheads are part of the magic of the quickening woodland. Some species, notably polypody ferns, are epiphytic on the limbs of trees, often in association with mosses, lichens and liverworts. Unlike ferns, these latter plant groups have no tubular system for conducting water and so are dependent for survival on colonizing moist sites.
Fungi differ radically from the foregoing plants in having no chlorophyll for making food reserves, so they must either live off decaying wood or parasitise living tissue. Their fruiting bodies-the mushrooms, toadstools and bracket fungi-appear mostly in the autumn.