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strated to be in every way superior. The Boxelder seed germinated 
poorly, making an uneven stand, and while in the seed leaf both Box- 
elder and Ash were much injured by cutworms, which did practically 
no harm to the opposite plats, where young trees were used. 
The seed plants required hand weeding, making cultivation the first 
year more difficult and expensive, and in the spring of the second year 
the seed plats had to be thinued to a single tree in the hill, again 
increasing the cost. A count made at the end of the first growing 
season (see Bulletin 20, S. Dak. Experiment Station) showed that the 
seed plat of Boxelder was a failure, while in the seedling plat 83 per 
cent grew. Of the Green Ash 89 per cent of the seedlings lived, while 
only 49 per cent of the seed grew. 
The following varieties were planted pure: Boxelder, Green Ash, 
Silver Maple, White Elm, Russian Poplar (Populus certinensis). As 
compared with mixed planting, the disadvantages of pure planting are 
very apparent in this plantation. The mixed plats in which shade- 
enduring trees were used as nurses are now so thick as to completely 
shade the ground, and no cultivation has been necessary in them for 
four years. The more valuable trees in them, such as Ash and Elm, 
are in better condition than when planted pure, having been benefited 
by the side shade of their more densely foliaged neighbors. In the 
pure-planted Boxelder plats, while the trees have grown quite as well 
as in mixed planting, they are of themselves of low intrinsic value, and 
hence when the Boxelders are gone nothing will remain. Used as a 
nurse, the Boxelder reaches small fuel size, and when it is removed 
there remains a grove made the more valuable by having used it. 
Silver Maple shows the same characteristics, planted pure, except 
that at Brookings the young trees winterkill and sprout from the 
crown, thus growing in coppice form. As before stated, the Russian 
poplar failed during the years of drought. 
In the Ash and Elm plats cultivation is still necessary seven years 
after planting. This fact alone makes the pure planting of these spe- 
cies inadvisable. The trees have not made as tall growth, and are 
much more forked than the same species in mixed planting. Trees 
planted in the plains are much more apt to head low than in forest 
regions because of the intense sunshine and the heavy winds. There 
is a constant use in western farms for pole timber, and its value is 
greatly increased by straightness and freedom from knots. If the 
young trees can be grown free of low branches their timber will be 
much stronger and more useful for all farm purposes. Hence the great 
importance of planting varieties the wood of which is useful in farm 
economy among others which wil) encourage length of stem and free- 
dom from branching. Quick maturing kinds like Cottonwood and 
Boxelder may be planted alone where the object is merely to secure a 
supply of cheap fuel, but even in this case the method is not economi- 
cal, since it could be accomplished with more durable species in mixture. 
