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or less hard and compact. Water speedily runs over the surface, carrying 
soil and debris, which it deposits in the beds of streams. Places which 
wash badly are exceedingly common and cause the loss of much tillable 
land. 
THE MODEL WOODLOT. 
After a review of the reasons for maintaining woodlots it is well to 
consider the organization of a model woodlot. 
Number of Trees.—It should contain the number of trees consistent 
with the most rapid development of the best timber. Trees should stand 
close enough in youth to stimulate growth in height and to produce long, 
clear trunks. As the stand approaches maturity more and more space is 
required for each tree until at last probably only one hundred and fifty to 
two hundred trees of the original three or four thousand remain per acre. 
Thinning is brought about naturally by the struggle for supremacy. 
Distribution and Soil Cover.—lrees should be evenly distributed over 
the entire area, always close enough together to prevent many direct rays 
of the sun from reaching the ground in summer, since the large openings 
give grass, a very dangerous enemy of forests, a chance to grow. The ideal 
soil is loose, porous, rich in vegetable mould and is covered with a thick 
mat of leaves and leaf humus to the exclusion of all grass and light-de- 
manding weeds. 
Forest Cover.—The trees which should be found in a woodlot depend 
upon two factors—(1) the economic value and (2) silvical characteristics. 
Such trees as black walnut, black cherry, ash, oak, maple and poplar have 
the greatest economic values. The other factor has to do principally with 
the soil, moisture and light requirements. For example, sugar maple re- 
quires rich upland soil and very little sunlight for its best development, 
while sycamore will grow on any wet soil if it has plenty of light. Thus 
we shall find in a model woodlot the species best suited to the soil, water 
supply and the uses to which the timber is to be subjected. In no case 
should there be any worthless species. 
Reproduction.—In order to maintain the desired acreage of our timber 
producing area some efficient method of reproduction is necessary. This 
is usually found in the presence of large and mature seed-bearing trees, 
which scatter their fruits over long distances until they find lodgment in 
places suitable for germination. Another method of reproduction is by 
