64 



PARASITES. 



"Dr. Eiley mentions having bred a Microgaster from the apple 

 leaf skeleton izer. We have also frequently obtained specimens of 

 an undescribed species belonging to the genus Bracon from the 

 larvae of this insect. 



REMEDIES. 



Concerning remedies, Prof. Riley {I. c. ) says: "A little hand 

 picking at the proper time would do much to prevent its inju- 

 ries, and I incline to believe that it may be extirpated by dusting 

 the trees with air-slaked lime." Prof. French has added the rec- 

 ommendation that the arsenites be used, and Prof. Forbes has 

 advised, in addition to this, that the fallen leaves in the nursery 

 be burned to destroy the pupae. 



Early in July, 1886, I made some experiments with Paris green 

 on skeletonizer larvae infesting nursery trees. The results showed 

 that spraying with Paris green in the proportion of one ounce to 

 eight gallons of water, effectually destroys the larvae without in- 

 jury to the tree; and from some partial experiments made at the 

 same time, which were interrupted by a heavy rain storm, I in- 

 cline to believe that half this strength of solution would be suffi- 

 ciently effective. 



The operation of spraying nursery stock with the arsenites or 

 other insecticides is much simpler than is generally supposed. 

 For stock of one year's growth all that is necessary is to go 

 through the field, lengthwise of the rows, with a wagon contain- 

 ing a barrel of the solution, having a hand-force pump and spray 

 nozzle attached, straddling about every tenth row, and spraying 

 the five rows on each side. In this way a field can be gone over 

 easily and rapidly and sprayed for the leaf roller, skeletonizer, and 

 ■crumpler at comparatively little expense. I presume that for trees 

 two or three years old it would be difficult to straddle the rows 

 with an ordinary wagon without injuring them; but this difficulty 

 may be easily avoided by omitting every eleventh row so that the 

 wagon can pass through at any time. 



Special pumps on wheels, with spraying apparatus attached, are 

 now manufactured for the purpose of spraying various 'crops with 

 insecticides, and these would serve the present purpose admirably. 



