Red spider on cotton (Tetranychus bimaculatus Harvey) . t seen) was one whichof badly infested pokeweed stalks The pest spread fanlike until itGOO feet from the pokeweed. Thein shape, comprised 13 acres, andwas general. While such a case as spots, with 25 to 100 per cent dam- I II I RED i • 11 I i: O > i iiI 111N . 13 NATlRAI • i\ l in il l l m. \i.| m 11 -. In both the seasons of L911 ami 1 ? >I_ red spider occurrence wa ~i severe throughout July and earlj August. The last two week of August in both cases, however, witnessed so greal n reduction ofthe pesl that l>\ the end of thai mo
Red spider on cotton (Tetranychus bimaculatus Harvey) . t seen) was one whichof badly infested pokeweed stalks The pest spread fanlike until itGOO feet from the pokeweed. Thein shape, comprised 13 acres, andwas general. While such a case as spots, with 25 to 100 per cent dam- I II I RED i • 11 I i: O > i iiI 111N . 13 NATlRAI • i\ l in il l l m. \i.| m 11 -. In both the seasons of L911 ami 1 ? >I_ red spider occurrence wa ~i severe throughout July and earlj August. The last two week of August in both cases, however, witnessed so greal n reduction ofthe pesl that l>\ the end of thai month il was hardl) noticeable,:i rule. This phenomenon, indeed, happens suddenly, and the agencies which work to produce il are unquestionably of greal economicvalue. The ageing and toughening of the leaves al aboul this timeni;i\ cause many mites to desert the cotton for other plants, butanother factor of probably much greater importance is the increasedabundance of several species of insecl enemies which seem to gaindominance nl jusl this m, « A-P] 1 •• 1 - ? t - £**** • i A* L ?i . .•» >-* i 0 \ severe example oJ red-spider work In a cotton Held Nenrlj all plant* In theI nre In the i ondll loi 8. 1 ertaln I?..k<-\\ • -i d stnlkflllnst ration. (Original i i MM \ I H IMI I I M 1 -. \- before mentioned, climatic conditions exert a marked influenceupon the welfare f the pest. During times of little rainfall andhigh temperature reproduction goes on h\ leaps and bounds; onthe other hand, long, heav^ rains work havoc to the red-spiderpopulation. In spite of the fad that the red spiders inhabit theunderside of the leaves, many are washed off by rains and many moreare destroyed by the upward bombardment of -and particles, whichmay always be seen coating the lower leaves after storms. In appear- true thai a few heavy rain-, especially if they continuefor -mne time, accomplish as much toward controlling the pest as 14 Till. I,K1) BPIDEB ON COTTON. a
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Keywords: ., bookauthorunitedst, bookcentury1900, bookdecade1910, bookyear1913
