. Bulletin of the Department of Agriculture. Agriculture; Agriculture. PROGKKSS REPORT ON THE KUlilil' < 0|;.\ BOKKR 25 appear upon the tender leaf blades surrounding 111 <- developing tassel. (Fig- 6.) Such injuries are caused by the feeding of the newly hatched larvae, and, while not economically important, this surface feeding affords a possible opportunity cor attacking the larvae by insecticidal means. The midrib of the leaf blade some- times is entered and tunneled, more particularly by the smaller borers, in the same manner and with the same result as will be described la
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. PROGKKSS REPORT ON THE KUlilil' < 0|;.\ BOKKR 25 appear upon the tender leaf blades surrounding 111 <- developing tassel. (Fig- 6.) Such injuries are caused by the feeding of the newly hatched larvae, and, while not economically important, this surface feeding affords a possible opportunity cor attacking the larvae by insecticidal means. The midrib of the leaf blade some- times is entered and tunneled, more particularly by the smaller borers, in the same manner and with the same result as will be described later for the stalk. INJURY TO THE TASSEL The tassel buds and the immature branches and main stem of the tassel are often entered and fed upon by the young borers (fig. 6) even before the tassel appears above the unfolding leaf blades. Often several adjoining tassel buds are webbed together with particles of frass and silk by the small larvae. In this condi- tion the infested tassel is very conspicuous after it appears above the unfolding leaves. Frequently the injury to the immature tassel stem causes the breaking over of the tip of the tassel even before it begins to expand. As the tassel expands and the buds begin to open the larvae continue to tunnel within the branches and the main stem. This injury usually causes the tassel, or the infested portion thereof, to collapse and break over. Such broken tassels (fig. 7), with masses of frass at the breaks, are very conspicuous and often afford the most noticeable sign of the presence of the insect. It does not necessarily follow, however, that because none of the tassels are broken over in a suspected field the insect is not present, as plants sometimes are attacked only at points lower down than the tassel or at a late stage in their development when the tassel or its stem does not attract the larvae. INJURY TO THE STALK Some of the newly hatched larvae, instead of tunneling within and feeding upon the tassel buds and tassel stem
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