350 MR. T. W. WOODHEAD ON THE 
Distribution of Dominant Woodland Trees and Plants of the 
Undergrowth in the Huddersfield District. 
Having determined some of the chief factors influencing the 
distribution of woodland plants iu typical areas, it remained 
to extend the observations over a wider area, and so discover 
to what extent the results were capable of more general 
application. Consequently similar observations were carried 
on over an area of 66 square miles and the results recorded 
on maps of 6-inches to the mile scale. 
This area is included in sheets 259 N.E. and S.E. 260, 
261 N.W. and S.W., 271 N.E., and 272 N.W. and N.E. of the 
6-inches to the mile Ordnance-Survey maps. 
The two maps (figs. 9 & 10, pp. 352-3) show these details on 
a greatly reduced scale. This reduction, however, made it 
impossible to indicate the many small details studied ; this will 
be easily understood if they are compared with the sketch-maps, 
figs. 1-5 and 7 &8*. "The map (fig. 9) shows the distribution 
of the dominant trees, viz.:—Coniferous trees, chiefly Pinus 
sylvestris, Oak (Quercus Robur, Linn.), and Birch ( Betula verru- 
cosa, Ehrh.); and shade-trees, chiefly Sycamore (Acer Pseudo- 
platanus, Linn.), Elm ( Ulmus montana, Stokes), and Beech (Fagus 
sylvatica, Linn.). Areas are also indicated where trees occur 
buried in peat, these are chiefly Birch. 
On comparing this with the undergrowth map (fig. 10) we see 
that the area covered by trees is relatively limited, while that 
covered by plants which are common in the undergrowth of 
the woodiands is much greater, especially to the west—i. e., 
species like Bracken (Pteris aquilina, Linn.), Deschampsia, Ling 
(Calluna Erica, DC.), and Bilberry (Vaccinium Myrtillus, Linn.) 
cover large tracts in a comparatively treeless region. We also 
see that while Bracken is absent commonly under shade-trees, 
it is not infrequently found there, and, on the other hand, it is 
not uncommonly absent under trees with an open canopy. 
The distribution of Vaccinium Myrtillus is very interesting, 
especially when considered in the light of observations on its 
distribution elsewhere and the history of the vegetation in this 
* In working out these details in the field I found it necessary to have a 
number of duplicate maps on which to record preliminary observations and 
build up the facts. To avoid the cost of many Survey Maps, tracings of the 
necessary areas were prepared and these were used as “ negatives” from which 
the required number of prints were made on Thornton's Universal Photo- 
paper; these proved very useful. 
