Red spider on cotton (Tetranychus bimaculatus Harvey) . ,i. Cross section of normal cotton leaf; . cross section ol cotton leal red spider. The puncture Is near lower right-hand corner. Highly magnifiedi tatbora Illustration I distorted, and drop. Figure 5 shows an uninfested cotton plant forcomparison with figure 7. infested. The lower have- usually are firstattacked, but infestation spreads upward until often only the barestalk and one or two terminal leaves remain, i Sir fig. s. i Suchplants almost invariably die. The injury to the leaf and the dis-coloration which follows the
Red spider on cotton (Tetranychus bimaculatus Harvey) . ,i. Cross section of normal cotton leaf; . cross section ol cotton leal red spider. The puncture Is near lower right-hand corner. Highly magnifiedi tatbora Illustration I distorted, and drop. Figure 5 shows an uninfested cotton plant forcomparison with figure 7. infested. The lower have- usually are firstattacked, but infestation spreads upward until often only the barestalk and one or two terminal leaves remain, i Sir fig. s. i Suchplants almost invariably die. The injury to the leaf and the dis-coloration which follows the feeding of the mites are easily under-stood by referring to figure 6, winch represents (a) the appearanceof healthy cotton leaf:tissues and (6) the condition of the tissueafter feeding by the pest. As previously intimated, the worst spotsof infestation arc cither to be found in close proximity to yards withIxtrders of violets or to a clump of pokeweed stalks. Large fields areprobably never completely damaged, bul -mailer fields frequentlybecom
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Keywords: ., bookauthorunitedst, bookcentury1900, bookdecade1910, bookyear1913
