New York Agricultural Experiment Station. 317 



The hexagonal folding fumigator has an advantage over all 

 other forms of so called box fumigators in, that it contains the 

 least amount of waste space, and that it can be folded into 

 small compass for transportation or storage. 



For fumigation of deciduous trees over ten and under sixteen 

 feet in height hexagonal folding fumigators can be constructed 

 and handled at less cost than can tents, but the additional ex- 

 pense for chemicals required by the folding fumigator would 

 probably more than counterbalance the difference. 



All forms of covers used in orchard fumigation have a dis- 

 advantage in that there is a limit to the size which can be 

 handled. As yet no single cover has been devised for trees over 

 20 feet high. Marlatt^ states that citrus trees 30 feet high are 

 fumigated in California by using two sheets, one overlapping the 

 other. (It should be noted that he describes the handling of 

 these tents by means of 25-foot poles with tackle. It is a 

 mechanical impossibility to use tackle of this size on trees over 

 25 feet high.) Lapping one sheet over the other and making a 

 tight joint may be possible on citrus trees and thorough enough 

 for " black scale," but could not be made to work on deciduous 

 trees for San Jos6 scale. 



It is not advised that any one attempt the building and hand- 

 ling of folding fumigators over 16 feet high and never more than 

 10 feet in diameter or with G-foot sides. We believe that fumi- 

 gators with 5 foot sides and 15 or 16 feet high can be handled as 

 easily as the 12 foot fumigators with 6-foot sides. When con- 

 structed over 12 feet high spruce rails cannot be used for stiles. 



COST OF FUMIGATION. 



So many factors have to be taken into account in estimating 

 the expense of fumigating trees in an orchard, that it is only 

 possible to give an approximate estimate of cost. Even this 

 must be conditioned not only by style of fumigating outfit used, 

 but also by size and shape of tree to be fumigated as well as the 



^Yeaa-book, U. S. Dept. Agi-. 1S9G:229. 



