36 HATCH EXPERIMENT STATION. [Jan. 



the lindens had been sprayed earlier, or about July 1, as 

 at the time of the first spraying the spot was beginning to 

 appear. 



None of the elm trees, either the sprayed or unsprayed, 

 developed much of the leaf spot. All that can be said in 

 favor of the sprayed trees is that their foliage remained green 

 longer than the other trees, and the trees retained their 

 leaves the latest of any. We estimate that linden trees 

 affected as these were, if sprayed twice during the season, 

 would result in a gain of from two to five per cent, in their 

 groAvth and development. The cost of spraying was insig- 

 nificant, as the trees were not large. The question involved 

 in all such instances is, whether the tree is worth the 

 expense. This depends on the owner's interest in such mat- 

 ters, and in the means and facilities to have such work done. 



Crops under Tent Cloth. 

 Much interest has been manifested in Massachusetts and 

 Connecticut in the last two or tliree years in growing Sumatra 

 tobacco under tent cloth. That the environmental condi- 

 tions of i)lants are greatly modified under tent cloth is avcII 

 known. Besides exerting a characteristic influence on the 

 texture of the plants, we might expect, from our knowledge 

 of the conditions which favor fungous infection, that the 

 conditions prevailing under tent-cloth culture would result 

 in producing in certain cases beneficial results. In some 

 instances tobacco growers have planted cucumbers, water- 

 melons, tomatoes, etc., on the border of tobacco beds planted 

 under tent cloth, largely as a matter of curiosity, to see how 

 they would develop under these conditions. So far as the 

 production of fruit is concerned, it may be stated that these 

 experiments have been a failure, because no adequate pro- 

 vision was made to fertilize the flowers. As a result of 

 this, plenty of fruit sot but did not mature. The foliage 

 of watermelons which was observed under tent cloth was 

 in excellent condition. We noticed, however, on a few 

 vines about a dozen leaves affected with AUernaria, which, 

 however, showed no tendency to spread. Muskmclons de- 

 veloped good vines and foliage, but towards the latter part 



