124 



HATCH EXPERIMENT STATION. 



[Jt 



in. 



together with the unusually severe drought occurring in the 

 summer of 1905. The occurrence of so many difterent fungi 

 on the pine, which especially predominated during the late 

 summer and fall, was very largely a secondary result of the 

 weakened condition of the tree caused by winter-killing. 



Relation between Soil Aeration and Germination 



AND Growth. 



For some time our attention has been given to the relation 

 existing between seed germination and plant development, 

 and soil texture and aeration. This problem possesses a 

 practical bearing, inasmuch as it underlies the question of 

 soil selection for specific crops. It is not our purpose at 

 present to go extensively into this subject, but only to touch 

 upon one phase of it. It is well known to gardeners and 

 others that aeration, or the presence of air in soils, plays 

 quite an important role in the development of seedlings. 

 This experiment was made to determine what effects forcing 

 air through soil would have upon germination and growth. 

 For this purpose we made use of loam placed in two boxes, 

 18 by 18 by 18 inches. In each box there was a round 

 funnel, 4y2 inches in diameter, buried under the soil 1^/2 

 inches from the surface. Both funnels were connected with 

 block tin tubes leading outside of the box, one of which was 

 attached for a period of six hours each day to a water blower, 

 and the other remained unconnected. Lettuce seed, which 

 is (|uite susceptible to aeration, was employed, and 1,500 

 seeds were placed in each box, and the necessary data per- 

 taining to germination, etc., were noted. 



Tabic shoioing Bcmlts of Aeration on Orowth of Lettuce Seedlings. 



1,500 Seeds in Eneh Box. 



