366 BOARD OF AGRICULTURE. [Pub. Doc. 



realized until about 1910, when a general investigation to 

 locate cases of the disease was begun. In 1911 and the spring 

 of the following year, so many cases of this disease were found 

 on imported pines at the time they reached this State that it 

 seemed wise to issue an order which would prevent their intro- 

 duction, and this was accordingly done, so that no new cases 

 can now be brought into Massachusetts. 



If this disease ever gets established in our forests, the at- 

 tempt at the reforestation of our wild lands, which is now an 

 attractive proposition, may as well be abandoned, and it has 

 seemed wise to take every possible precaution to prevent this. 

 With no new stock liable to have the disease, coming in, the 

 problem restricts itself to the discovery and elimination of all 

 cases already present in the State. This is best accomplished 

 during the months of May and June, when the trouble is most 

 evident to the eye, on the pines, and during August, Septem- 

 ber and October, when it shows on currants; for this peculiar 

 disease, after living in the pine for a greater or less number of 

 years, finally breaks through from the inside, and on the sur- 

 face of the bark produces its spores, which pass to the currants 

 and there produce another stage in the leaves. In the fall this 

 stage in its turn produces spores, and, if these pass to jiines, 

 they infect the trees. 



From this it follows that pines may have the disease for 

 several years before it shows, though usually traces of it are 

 evident. When the spores are forming on the bark in the 

 spring, however, the trouble is easily recognized. Currants 

 examined in the fall also show the disease if it is present, and 

 by an inspection of both of these kinds of plants the trouble 

 can be positively located. 



All white pines and other five-leaved pines received by nurs- 

 eries in Massachusetts have been carefully inspected now for 

 several years, and all sales from infected blocks stopped. Some 

 sales, however, were made before any knowledge of the disease 

 was available, and, as far as possible, all of these trees have 

 been traced and inspected where they now are. Whole blocks 

 of nursery trees not showing any evidence of the disease have 

 been destroyed, simply because one or two in the block were 

 affected, at a loss of thousands of dollars to the nurserymen; 



