THE VEGETATION OF WOODLANDS. 9 



regarded as a feature to be noted in the study of woods. A 

 good deal may be learned by observing it. Thus, if 

 on examining a wood one finds beneath the canopy a dense 

 vegetation with all the layers represented, it is fairly safe to 

 assume that the canopy is open, that the soil is moist and 

 fertile, and that ground game commits little damage. On the 

 other hand, if the intermediate layers are absent, and the ground 

 is bare or covered only by a low carpet of plants, this indicates 

 a dense canopy or a dry, poor soil, or the ravages of rabbits or 

 grazing stock. 



The trees forming the canopy have a marked influence on 

 the underlying vegetation. If the trees are of middle age and 

 grow at equal distances apart, the greatest amount of light 

 passes through a canopy of ash or birch, less light is admitted 

 by oak, less still by elm and sycamore, least of all by beech. 

 The larch amongst conifers allows most light to pass because it is 

 deciduous and has no leaves from October to May. Scots pine 

 casts shade till it is tall and aged, while spruce scarcely ever 

 allows much light to pass. Where little or no light can pass 

 through the canopy, as in the case of evergreens, there is little 

 or no ground-vegetation. In the case of deciduous trees, it is 

 usual to find a vernal ground-vegetation consisting of early- 

 flowering plants, which appear above ground several weeks 

 before the tree canopy unfolds, e.g., anemone, primrose, wood 

 hyacinth and celandine. These plants are provided with 

 underground stores of food-material, and form their flower-buds 

 during the preceding year, so that in a short time they flower 

 and seed. The leaves follow and, utilising such light as is 

 available, they prepare a food-store for next season. The 

 kind of canopy exerts an influence on this later leafing period. 

 Under an open canopy of oak or ash the leaves can remain 

 active, and the later leafing bracken and other wood ferns can 

 also maintain an existence. Under a canopy such as beech, 

 which permits little light to pass, the activity of the ground- 

 vegetation is so interfered with that the plants are stunted or 

 succumb altogether. 



The dominance of any particular tree depends naturally on 

 climate and soil, but one finds everywhere evidence of man's 

 operations. Under natural conditions the dominant trees are 

 generally limited to one or a few species, but when planting is 

 done any number of species may be present. The forester 



