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These insects are probably more beneficial than injurious. The more 

 valuable trees might be protected with a lead arsenate spray. Galerv- 

 cdla luieola, Miill. (elm leaf beetle) continued to be a serious pest of 

 elms, particularly the European varieties. A study of climatic 

 conditions revealed an interesting correlation between arrest in the 

 development of this insect and unseasonable cold weather. Earlier 

 studies show that under normal conditions, oviposition by G. luteola- 

 begins in the latter part of May and continues, through June, being 

 at its height in the middle of the month. The month of Jane was 

 therefore divided into three ten-day periods, and the maximum, 

 minimum and effective temperatures were tabulated from 1905 to 1914. 

 These tabulations are given in full, and in conjunction with the tentative 

 conclusions advanced, give an approximate basis for determining the 

 probability of serious injury locally before the brood has developed 

 to such an extent as to damage the trees materially. In May, a fair- 

 sized colony of Lymantria {Porthetria) dispar, L. (gipsy moth) was 

 discovered in Westchester county. The control measures adopted 

 proved efficient, though as yet extermination cannot be definitely 

 said to have been secured. A scattered infestation of Eiiproctts 

 chrijsorrJwea, L. (brown tail moth) was discovered on Fisher's island 

 and the eastern end of Long Island ; the pest had very probably 

 drifted with the winds fiom the adjacent mainland of Connecticut. 

 The Jassid, Alehra albostriella, Fall. (Norway maple leaf hopper) 

 caused an unexpected and severe injury to Norway maple at Newburgh, 

 N. Y. Chionaspis pinifoliae, Fitch (pine leaf scale) was again reported. 

 One lot of material was heavily infested by Chalcid parasites, especially 

 Asjndiotiphagus cifrinus, Craw. ; smaller numbers of Aphelinus 

 mytilaspidis, Le B., were obtained. Another species, Perrissopterus 

 pulchellus, How., has also been reared from this pine scale. Leucaspis 

 japionica, Ckll., infested Norway maples at Stamford, Conn. Other 

 scales noticed were Physokermes piceae, Schr. (spruce bud scale) and 

 Phenacoccus acericola, King (false maple scale). Tetraleurodes mori. 

 Quaint, (mulberry white fly) was observed on Kalmia latifolia 

 (mountain laurel). 



Forest tree pests : — The season of 1914 was marked by an extension 

 of the ravages of Malacosoma disstria, Hb. (forest tent caterpillar). 

 The hickory bark beetle [Scolytus quadrispinosus, Say], Rhyacionia 

 (Evetria) huoliana, Schiff. (European pine shoot moth), and Monaithro- 

 jpalpus huxi, Lab. (box leaf midge) also occurred. Tortrix fiomferana, 

 Clem, (spruce bud moth) was reported upon ornamental spruces ; 

 in one instance, at least, the blue spruce was attacked. Early spraying 

 with arsenate of lead, 3 lb. to 50 U.S. gals, of water, is the most 

 promising method of checking this insect. Cacoecia {Archips) cerasi- 

 vorana, Fitch, was unusually abundant in the latter part of June in 

 southern Rensselaer and northern Columbia counties. This leaf- 

 feeder confines itself to chokeberry and is therefore of no economic 

 importance. Elaphidion villosicm, F. (maple and oak twig pruner) 

 was unusually abundant along the Hudson valley and numerous 

 reports of injury were received from the vicinity of New York City. 

 Tibicen septetndecim, Linn, (periodical cicada) causes injury by 

 oviposition ; a case was reported where badly affected trees were 

 much stunted. 



(C238) c2 



