THE DOCK FALSE- WORM. 37 



or other repellent materials safe to the trees, provided the lower 

 limbs are kept well up from the ground and any props used are also 

 banded. The bands should be applied about August 15, and not 

 later than September 1, and under ordinary conditions will remain 

 effective until the fruit is picked. A satisfactory sticky substance 

 may be made by heating 5 pounds of resin until it is melted and then 

 adding 3 pints of castor oil, stirring thoroughly. In using any sticky 

 substance it may be applied directly to the trunks of the larger trees, 

 but if there should be any occasion to use it on trees not more than 

 three or four years old (trees of this age sometimes bear a few apples), 

 a band of paper should first be tightly wrapped about the trunk and 

 the material applied to this, otherwise it may roughen the bark of the 

 tree. Needless to say, this paper band should be removed after the 

 fruit is picked. A band of this substance one-sixteenth inch thick 

 and. 3 inches wide is sufficient and will cost about 3 cents a linear 

 foot. The cotton bands are cheaper, costing from 1 to 2 cents a 

 linear foot for bands 6 or 8 inches wide. It takes only a few minutes 

 to apply either material to a tree. 



SUMMARY. 



The dock false-worm is the larva of a sawfly (Ametastegia glabrata 

 Fallen) found all over Europe and in Canada and the northern part 

 of the United States, from the Atlantic to the Pacific. 



The larva is a green, wormlike creature, which feeds on dock and 

 related plants; frequently, however, where conditions are favorable, 

 it finds its way at maturity into apple trees, where it bores into the 

 apples to hibernate, making them unsalable. 



The dock false-worm has four generations annually, each generation 

 occupying roughly a month, except the fourth, the larvae of which 

 hibernate and complete their development the following spring. 

 Only the larvae of this last generation are known to bore into apples. 



A number of parasites have been reared, both from the egg and 

 from the full-grown larva, and while these are valuable in partially 

 controlling the false-worm, probably they will never control it 

 absolutely. 



Apples may be protected from this insect by keeping the orchard 

 free of dock and other food plants, or, where this is not possible, 

 by banding the trees with cotton or some sticky substance safe to the 

 trees in the latter part of August and leaving the bands on until after 

 the fruit is harvested. 



