MONTANA STATP] P,()AKI) OF HOUTICULTUKE 



71 



Figure 2. White pine tree dying from the effects of the rust. Note the in- 

 fection on the main trunlt and side branches: also the blisters which have broken 

 through the bark, which contain the spores which are carried to currant and goose- 

 berry bushes. (Loaned by the courtesy of the Bureau of Plant Industry, U. S. 

 Department of Agriculture.) 



the wind or carried by birds and insects, and may often be carried 

 on the clothing of individuals. These can not reinfect pine, but 

 should they by any of the above means happen to reach currants or 

 gooseberries, another stage of the disease is started on the leaf, 



