126 EXPERIMENT STATION. [Jan. 



now, as it is a matter of general observation that many of the 

 trees which burned this season commenced to recover a few 

 weeks after being affected. 



Strong, dry winds are important factors in producing sun 

 scorch, and an excellent illustration of this may be found in the 

 ninth annual report of the Hatch Experiment Station (pp. 81, 

 82) ; but, technically speaking, the cause of sun scorch is the 

 exhalation of watery vapor from the foliage in excess of the 

 amount of water supplied by the root s. Sun scorch is a common 

 phenomenon, peculiar to many plants, and, while its occurrence 

 on the pine appears to be new to most people, we have observed 

 it for twenty-five years to a very limited extent. The cause of 

 the recent sun scorch of the maple and white pine is to be found 

 in certain meteorological conditions, but the immediate cause 

 may be traced to the peculiarly dry winds of July, together 

 with the inability of the roots to supply sufficient water. The 

 effect of sun scorch is more marked on the western side of a tree 

 or forest, — a fact which has been noted by various observers 

 besides ourselves. 



4. Premature Defoliation of Trees. 

 The premature defoliation of trees, which has been very 

 common this season and which occasioned considerable corre- 

 spondence, as usual, gives rise to much unnecessary anxiety. 

 Among the many well-known causes of defoliation maybe men- 

 tioned severe drought, and even excess of water may cause it. 

 Elm trees, however, are likely to lose their leaves both in early 

 summer and fall, and this is also common to other trees ; but 

 the loss of foliage in the case of the elm is seldom serious 

 enough to cause alarm ; and even the shedding of the twigs of 

 the elm, which occurs to considerable extent, often periodically, 

 generally causes little damage. 



5. Asparagus Exist. 

 This disease has been more prevalent than usual the past 

 summer in certain localities, but less so in others. It has in 

 some places affected those beds which in ordinary seasons 

 seldom show outbreaks except in the late fall. The rust 

 occurred in a rather unusual form for this section, since as a 



