VARIOUS FORCING METHODS. 89 



earth about the hills, will also assist greatly in smother- 

 ing the weeds, besides having considerable fertilizing 

 value and acting as a partial mulch. 



It is customary with many gardeners to place head- 

 less barrels or boxes over the hills in spring in order 

 to force an extra growth of stalk. By this plan the 

 stalks shoot up long and slender but do not weigh more 

 than if left to grow in their natural manner. They 

 are rather more tender than stalks not forced, but the 

 process somewhat weakens the hill, and it is on the 

 whole not profitable. 



Portable Forcing House. — In his forcing book, Pro- 

 fessor Bailey describes a unique plan for open field forc- 

 ing by installing a system of surface steam pipes to be 

 covered with a movable roof of muslin. In spring the 

 cloth roof is removed. 



