PHENOLOGY OF FOREST TREES 141 



Catalpa (catalpa speciosa) 

 May 13, buds opening 



Willow (salix nigra) 

 May 13, leaves out 



The spring of 1909 was decidedly backward in seasonal growth but 

 the weather was not severe enough to cause a marked freezing back. 

 A few of the trees that normally develop early had their buds start 

 in March, but the subsequent weather was just cold enough to retard the 

 growth already made and not sever enough to kill this slight growth. 

 Later when warm weather did come most of the species made an ex- 

 ceptionally rapid development and there seemed to be less variation 

 between the different species, than is the case in a normal season. 



^ 



