132 Bulletin 224. 



spraying, we counted the egg-clusters laid on the vines. As all of the 

 eggs are always laid under the loose bark on the vines, their presence 

 or absence is a much better and surer test of the number of grubs that 

 may later attack the vine than to dig around the roots and count the 

 grubs one may chance to find in the soil. In July Mr. Spencer 

 reported {The Grape Belt, July 24, 1903) the following results from 

 spraying with arsenate of lead at the rate of 4 pounds in 50 gallons 

 of water: Plot No. 1 was not sprayed; the foliage was much eaten by 

 the beetles; and 97 egg-clusters were found on 10 vines. Plot No. 2 

 was spraj'ed once thoroughly about the time the beetles emerged 

 from the soil; there was but little feeding on the leaves; and only 

 seven egg-clusters were found on 10 vines. Plot No. 3 was sprayed 

 thoroughly about the time the beetles emerged and again about 

 eight days later; there were scarcely any of the characteristic "mark- 

 ings" of the beetles on the leaves; and only one egg-cluster was 

 found on 10 vines. The egg-clusters on the sprayed vines averaged 

 only about 15 eggs each, while those on the unsprayed vines averaged 

 twice as many. This work was done in the most thorough and accu- 

 rate manner by the junior author, Mr. Johnson. These striking 

 results whereby more than 95 per cent of the eggs were apparently 

 prevented from being laid, were certainly very encouraging. It 

 should be said, however, that there were contrary opinions in regard 

 to the efficacy of this spraying (Bulletin 72, N. Y. State Museum, p. 41. 

 Rural New Yorker, June 4, 1904, p. 449). However, another reliable 

 vineyardist also sprayed a large part of his vines but once wth the 

 arsenate of lead, and he felt very sure that he accomplished much 

 toward controlhng this destructive pest; and a superficial examina- 

 tion of his vines in comparison with a neighbor's gave very encourag- 

 ing results.* 



These encouraging results led many of the vineyardists in the 

 infested region to arrange to spray in 1904. 



Experiments in 1904. — This Station also determined to get con- 

 clusive evidence, if possible, one way or the other in 1904. Fortu- 

 nately, a large vineyard was placed at our disposal into which a 

 swarm of the beetles had migrated and fed extensively from a badly 

 infested vineyard across a meadow 30 or 40 rods away the preceding 

 summer. This migration of the beetles in a body from one vineyard 

 into another thrifty one, affording better pasturage for themselves 



*Others who examined this vineyard for the grubs in October reported that "the 

 good results were more apparent than real," but the owner, who was prevented 

 by serious illness from showing the sprayed and unsprayed portions, tells us that 

 the wrong vines were examined. 



