EVAPORATION IN PENNSYLVANIA 215 



off. These records, therefore, about cover the growing season 

 of the chestnut in this region. It will be noticed that there was 

 greater evaporation in the spring of the year than at any other 

 season. 



The hill was covered at the time of the American Revolution 

 with a mixed growth of conifers and deciduous trees; a large per- 

 centage of the latter chestnut. The present orchard was grafted 

 on the third generation of chestnuts since that time. At present 

 a young, dense growth of coniferous and deciduous trees is appear- 

 ing on the hill. 



Judging by the growth, these climatic conditions appear to be 

 nearly the optimum for deciduous trees of the temperate zone, 

 especially for the chestnut tree. 



THE PLANT Wf)RI.n. VOL. 17, SO. 7, 1914 



