260 



REPORT OF THE 



No. 3 



roots, ascribable to a drying-out that takes place in periods of drought in shallow 

 or leachy soils. The result is that at the time the new needles are expanding, 

 there is a sudden demand for water that cannot be supplied and, in consequence, 

 the young needles turn pale and then redden from the tips downward. Owing 

 to the dry weather experienced last summer (1921), the blight, while not as 

 abundant as in 1918, was more sharply defined than in 1920. The forest com- 

 missioner for the State of Maine reports that a similar situation has prevailed 

 in the pine forests on sandy soils in the southern part of Maine. But white 

 pine {Pinus Strobus) is not the only tree affected in the blight areas, although 

 it probably suffers much more severely than other types; proof is accumulating 

 that shows that other timber species are involved to a greater or less extent, 

 dependent on their relative susceptibilities. A full account will be published 

 when the investigations in hand have been completed. The status of 633 white 

 pine trees, whose history has been followed since 1918, is summarized in the 

 table that follows: 



Blighted trees studied 358 



Checks (healthy trees) 275 



Of the checks, two only have developed blight, and under known condi- 

 tions. They blighted in 1919, following a partial lifting of the thin soil cover 

 and its permanent displacement from the bed of coarse broken rock on which 

 it lies — the action of ice. These trees died in 1921. The blighted trees have 

 been divided into two classes: (1) those with trunks 6 inches or less in diameter 

 (b.h.); (2) those with trunks more than 6 inches in diameter. 



From the results obtained, it is reasonable to conclude: (1) that young 

 stands are not likely to be seriously depleted by needle blight; (2) that injury 

 to heavily blighted mature stands may be so great as to be a deciding factor 

 in determining the time of harvesting. 



(2) Butt Rots. 



Butt or stump rots constitute the outstanding destructive agencies at work 

 in our Ontario forests. No type of forest is exempt, and every mature stand 

 becomes more and more susceptible with increasing age. Butt rots, once estab- 

 lished, continuously decrease stumpage values; they are also responsible for 

 most windfalls, and so for the vast amounts of debris that litter the floors of 

 our forests, affording a limitless supply of highly combustible wasted materials. 

 There are various types, but all are due to the action of parasitic fungi. For- 

 tunately, they are almost altogether restricted to mature or suppressed timber; 

 young trees are practically immune. This fact greatly simplifies the problem 

 of control. In this connection, it is in place to state that any effective plan 

 of scientific forest management is bound to take cognizance of the part played 

 by butt rots in the economics of the forest, and the administration of any such 

 plan will not only secure a maximum yield from the forest, but will also make 

 a long stride forward in the matter of fire control. 



