446 Agricultural Experiment Station, Ithaca, N. Y. 



At the outset, it should be said that the phenomenal injury 

 wrought by last winter was probably not wholly the result of low 

 temperature. The drought of the last summer and fall no doubt 

 augmented the injury. It is well known that trees suffer more 

 from cold weather when the ground is very dry. I have compiled 

 some figures from the reports of our meteorological bureau to 

 show the conditions existing last winter. It will be seen that the 

 total rainfall for last year was about twenty-eight and a half 

 inches, whilst the normal precipitation is thirty-five to forty 

 inches. During the period from July to December, inclusive, of 

 1895, the rainfall was less than sixteen inches, which is two and 

 a third inches below the rainfall of the like period of 1894, even 

 though that period was also a very dry one. 



There are probably two ways in which the effects of a drought 

 augment winter injuries. In the first place, the tree is probably 

 weakened in vitality by an excessively dry season, and is thereby 

 unable to endure so great exposure to cold. In the second place, 

 there is evaporation of moisture from trees during the winter 

 season, and if the ground is very dry this loss cannot be readily 

 met; and the tree thereby " freezes drj'," a condition which every 

 nurseryman knows is generally fatal to trees. The extent to 

 which loss of moisture may take place through the bark of dor- 

 mant twigs may be determined by cutting off the twigs and 

 quickly sealing over the ends with wax, weighing them, and then 

 detecting the loss in weight from time to time. The following 

 figures of such measurements will serve to emphasize the fact 

 that moisture is lost from winter twigs, although they are not 

 designed to show the actual rate of this loss when the twigs 

 occupy their natural position on the tree. 



April 7th, a cion of apple weighing 4.425 grams was placed on 

 a balance, and the loss by evaporation measured at intervals dur- 

 ing three days. The cut end of the cion was sealed with wax to 

 confine evaporation to that which may take place through the 

 bark. The balance or scales was placed in a living room, where 

 the readings could be taken at frequent intervals. It will be 



