Insect pests of farm, garden and orchard . Fir,. 9S.—(I. wheat-straw allVcliil \>y juiiil-woriii; h,.uhilt ;is seen IVoin iilxivc. (AlU-r Rik-y.) INSECTS INJURIOUS TO SMALL GRAINS 137 woody in character, and contains from 3 or 4 to 20 or more yel-lowish larvae, about one-eighth inch long when full-grown. TheselarvsB remain in the straw until the following spring, when theyissue as adults and commence again the life cycle in the new damage is done by the worms cutting off the sap supplyfrom the head, causing it to become shortened, containingcomparatively few kernels, and such kerne
Insect pests of farm, garden and orchard . Fir,. 9S.—(I. wheat-straw allVcliil \>y juiiil-woriii; h,.uhilt ;is seen IVoin iilxivc. (AlU-r Rik-y.) INSECTS INJURIOUS TO SMALL GRAINS 137 woody in character, and contains from 3 or 4 to 20 or more yel-lowish larvae, about one-eighth inch long when full-grown. TheselarvsB remain in the straw until the following spring, when theyissue as adults and commence again the life cycle in the new damage is done by the worms cutting off the sap supplyfrom the head, causing it to become shortened, containingcomparatively few kernels, and such kernels as develop are aptto be small and shriveled from lack of nourishment. Also becauseof the brittleness of the straw high winds are apt to break muchof it down.—Gossard. The presence of the pest is always indicated at threshing by. Fig. 99.—Wheat straw-worm (Isosomn grande Riley): o, ventral view; b, sideview of larva; c, antennae; d, mandible; e, anal segment, ventral view; /,adult female; g, fore-wing; h, hind-wing; i, aborted wing, (.\fter Riley.) short, hard bits of straw, containing the larvte, which arc carriedout with the grain instead of going over in the straw. It hasusually been considered necessaiy to separate and burn these,l)ut Professor F. M. Webster finds that the larvtc in them areprobably killed in threshing, as he has been unable to rearadults of cither the joint-worm oi- lis paiusites from such bits ofstraw. Coiilrol.—A rotation of the wlu^at crop is of })rimary impor-tance in the control of this pest, and whcic wheat is not plantedon the same land and is sown as far from that of the previous 138 INSECT PESTS OF FARM, GARDEN AND ORCHARD year as possible there will be but little damage. It is obviousthat the stubble should be plowed under where possible, or burnedduring the late fall or win
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