Early Development of Chestnut Sprouts. 41 



factor being "present in trees only during a limited period at 

 the beginning of the growing season, and almost entirely absent 

 *in summer when the greatest amount of water is used." 



Effect of Light and Shade on Height Growth. — Measurements 

 were taken on two adjoining plots similar in slope, aspect and 

 soil conditions, but differing in light conditions. In one, a clear 

 cutting had been made three years ago, while in the other, timber 

 for ties, posts and poles had been removed at the same time, 

 leaving still a rather full crown cover, density about .6. The 

 results are here summarized : 



Period. Under Full light. Partial Shade. 

 1 st year, 5.6 feet 5.1 feet 



2nd " 4.0 " 2.4 " 



3rd " 2.9 " 1.5 " 



Total 12.5 " 9.0 " 



The difference in amount of growth in height is much the least 

 for the first year. In the second year the sprouts in the open 

 make a growth of 66 per cent, greater than those in the partial 

 shade, while for the third year the increase is 93 per cent. These 

 results reaffirm the statement elsewhere made concerning the 

 relatively high tolerance of sprouts during the first year of life 

 As the food supply in the parent stump diminishes and the 

 sprout comes to depend to a greater degree upon the products 

 of photosynthesis its tolerance diminishes. The rate is seen to 

 be relatively rapid if, as is probable, the conclusion is warranted 

 that the slower rate of growth results from a diminished supply 

 of light. 



There is still a greater difference in diameter growth under the 

 two conditions. Sprouts growing under a moderate shade do 

 not even by the third year attain the stout form which is usual 

 with sprouts in the open. The decimation of sprouts in shade 

 is to be found in a following section. 



Effect of soil conditions on Height Growth. — The amount of 

 annual growth in height for each of the years was measured on 

 three year old chestnut sprouts, in each of the four different for- 

 est types, to determine the influence of site quality. The Maltby 

 tract contains in small plots a wide variety of site conditions. 

 There are at least three distinct site qualities with regard to 

 moisture and depth of soil, where the Chestnut forms a promi- 



