STORAGE SHEDS 139 



field they are driven into these sheds, the team removed, 

 the building closed up and the trees exposed to the fumes 

 of hydro-cyanic acid gas. This is used primarily against 

 the scale insects and has little or no effect upon any of the 

 fungus troubles. The process is always attended with 

 some danger as the gas is extremely poisonous. It re- 





FIG. 65. Hauling the Trees to the Storage House. 



quires from twenty to thirty minutes to fumigate a load 

 of trees. 



Storage Sheds. Where nursery trees are grown to any 

 considerable extent, some arrangement will be necessary 

 whereby the trees can be graded and packed for shipment 

 during the winter months. Where the winters are too 

 disagreeable to work out in the open, sheds must be pro- 

 vided. In the colder states these must be built substan- 

 tial enough to hold a large number of trees and sufficiently 



