350 МН, R. S. ADAMSON : AN ECOLOGICAL STUDY 
in groups and not as scattered trees. Three forms occur in the wood: 
the Dutch Elm, U. hollandica, Mill., which is confined to the edges ; 
another species of Elm, which appears to be U. satira, Mill., is much more 
numerous, it produces suckers freely. Ulmus glabra also occurs. * 
Betula, Birch, with the exception of a solitary (single) tree, is confined to 
the loam area, where it is fairly abundant. Both forms of the tree occur, 
much the commoner being В. tomentosa ; the other, B. alba (= В. verrucosa), 
is represented by a few individuals only. | 
Pyrus torminalis, Service Tree. About five or six trees of this species 
occur in the wood, all on the clay ; this is the only locality in the county. 
Some of the trees are remarkably fine examples; the largest has a cireumference 
of 5 ft. 6 ins. at a height of 4 ft. from the ground. This tree was at one 
time marked for felling, but the owners refused to allow it to be cut down. 
P. torminalis is mentioned by West f as being probably extinct from the 
county. 
Pyrus Malus, Crab-Apple. A single large example of this occurs in the 
wood. The apple is more abundant in some of the other Ash-Oak woods in 
the county. 
Acer campestre, Maple. Several small trees of this species occur scattered 
through the Ash-Oak part of the wood. Shade-bearing trees, such as 
Sycamore, Beech, &c., ате quite absent, and the wood is entirely free from 
planted conifers. 
Shrubs. —All over the clay part of the wood there is a thick layer of 
coppiced shrubs. On the loam area shrubs are much less abundant, and in 
parts almost absent. The shrubs are cut in definite areas, one each year, the 
rotation being about 18 years. The length of rotation for coppice shrubs 
varies in different parts of the country ; thus the average rotation in Kent is 
10-15 years, while in Somerset $ it is 10-12 years. 
Corylus Avellana, Hazel, is the dominant shrub all over the wood, either 
. pure or mixed with Ash or other species. Hazel occurs sparingly on the loam. 
Fraxinus ewcelsior is also extremely abundant and in large parts shares 
dominance with Corylus, or locally on small areas it may occur pure. Many 
of the ash shrubs are growing from extremely large stumps, which seem a 
further indication of the former greater importance of the species. 
Acer campestre is also abundant, but not nearly so much so as the two 
former. Both the type form and the variety leicarpon occur in the wood. 
Ulmus sativa. А small patch of shrubs of this occurs in one part, quite 
remote from the standard elms. This form has very small leaves and very 
large cork-wings to the stem. 
* For the identification of these Elms I am indebted to Dr. C. E. Moss. 
T West, 1898, р. 247. t Moss, 1907, р. 52. 
