fcd'rl'ON APHi^. 



ill 



cloudy Avi'atiicr, aphis becomes move a])undaiit and suddenly appears over 

 larg-e ai'eas. 



Plant-lioe excrete a sugary 

 liquid, wliicli, falling- on the 

 leaves below, dries to a sticky 

 coating. This appearance on 

 the leaves is a sign of the pest 

 and is familiar to cultivators. 



Many insects attack the 

 cotton aphis and are very im- 

 portant checks upon it ; these 

 are described in a later section 

 under beneficial insects. These 

 insects should be familiar to all 

 who grow cotton and should not 

 be destroyed in error as injuri- 

 ous insects. 



The treatment for cotton 

 aphis lies in spraying with a 

 contact poison, doing tliis when 

 the first colonies appear on the 

 cotton and not delaying until 

 with cloudy weather they spread 

 over the whole field. If culti- 

 vators Avere familiar with aphis 

 and checked it as soon as they 

 first saw it, it would never 

 become so serious a pest. 

 Without this, large areas may in cloudy weather become aiffiected, and 

 though the pest is principally one on farms and experimental cultivation, 

 it is also an important field pest. 



Fig. 129. 

 CoHon Aphis, tcint/ed femalo. 

 {^Magnijied jifleen times,) 



Minor Pests. 



There are a iiumbei' of insects which attack cotton casually, doing as 

 ft rule no harm but possibly injurious in unusual seasons. The Wliite 

 "Weevil ^ is a small beetle, of a dull Avhiie colour, found upon the leaves of 

 all varieties of the cotton plant almost throughout the year. It bites the 

 leaves of the plant, eating in from the edge. It is most conspicuous from 



^ JIi/UocerKs inactdosia: Des L. (Curculionidii'.) 



