EXPERIMENT STATION BULLETINS. 121 



4. THE STEAWBERRY LEAF-ROLLER. 



( Phoxopteris comptana. ) 



One of the most troublesome insects of the season of 1898 was the strawberry leaf- 

 roller (Phoxopteris comptana) .* From all oyer the southern part of the State, 

 wherever strawberries were grown, came complaints. Specimens of the curled leaves 

 were sent us from Three Rivers and the adult moth was bred from them. The cater- 

 pillars are small yellowish or green "worms," which feed on the leaves and cause them 

 to curl up tightly into little clumps, which are then bound together with a silken 

 web. Often the enclosed places are partially lined with the same material, making 

 a nest. The caterpillars or larvae may be foiuid usually by pulling apart some of the 

 furled leaves. They vary in color from pale yellowish to quite a decided green, and 





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Fig. 5. Strawberry Leaf-roller, Phoxopteris com'ptana. (Original.) 



when full grown are about one-third of an inch in length, slender and gently tapering. 

 The adult winged form, not seen so often, is a very small and delicate moth, reddish 

 brown and dusky in color, with black and white markings and about one-fourth of 

 an inch in length, while the extended wings measure a little less than half an inch. 



This dainty little moth comes forth early in the spring and lays its eggs for the 

 first brood on the young strawberry leaves. These eggs hatch and the "worms'" or cater- 

 pillars appear in June. If numerous, they devastate the strawberry beds and then, 

 becoming adults, l«,y luore eggs in September. These eggs hatch and the young 

 "worms" haA'e just al )ut time enough to become full-grown and go into the ground 

 for the winter. 



REMEDIES. 



After the first year of course no poison should be used on the plants before the 

 berries are gathered, but directly after gathering the berries, or during the tirst year 

 before the plants bear, the ])lants should be cut off close with a mowing machine and 

 burned. The field may then be sprayed with Paris green and lime, which will serve 

 to kill numbers of the full-grown worms in the leaves and also to poison what young 

 larvae may come from the eggs already laid. The spray, of course, should be reiieated 

 as long as any caterpillars remain. Tliis metliod should ]U(ne of great benefit and 

 the regular rotation of ciops will also be found useful. In some instances the lields have 

 been burned over, with good results, instead of cutting with a machine. This was 

 done about the time that the second brood of worms appeared. 



Tlie worms are easily killed with a spray of Paris green and lime, but as this must 

 not be used before the wheat is harvested, some otlier remedy is often required, and 

 this is found in kerosene cmulsioii. Obviously tliis must not be sprayed on ri])ening 

 fruit, but the spray must be applied in time to allow the oil to evaporate before the 

 fruit is picked. If this is done as soon as the worms appear and repeated until just 

 before picking time it will ])rove a comparatively easy task to keep the worms in 

 check. It must be remembered, however, that kerosene emulsion req\iires nnich more 

 careful application than the arsenites, for each worm must be hit to be killed. After 

 the crop is harvested the plants sliould be mowed and treated with Paris green as 

 previously advised to guard against tlie appearance of the pest next season. 



* The hyiiieno])terons iiara^^ite Teineliicha cnoki an«l |)erilaiii)>ut) t-vaneus were brt'd frniu this iiKitli. 

 They were (k'ttTinincd l)y Mr. Win. .\shme;iil of the l»ei>artiiient o^ .Agriculture, Wanliington 1). C. 

 through the kindness of I>r. L. (). Howard. 



