INSECTS AFFECTING PARK AND WOODLAND TREES I I 



The two winged flies or Diptera include comparatively few species 

 which are injurious to forest or shade trees, and most of these are of slitrht 

 importance. The gall-makino- midges, Cecidomyidae, cause deformities in 

 various plants, but ordinarily they are of little commercial importance. 

 They are easily distinguished from other galls, if they contain inhabitants, 

 by the peculiar jumping larvae which by bringing the extremities together 

 and then suddenly straightening, propel themselves an inch or more. 



The beetles or Coleoptera are a group which includes some of the most 

 important and destructive enemies of trees. The llattencd, metallic Bupres- 

 tidae are frequently met with in bright daylight, and their legless, white 

 larvae are easily recognized by the enormous, flattened head and the more 

 or less flattened body .segments. They usually make wavy, irregular 

 galleries. 



The long-horned l)orers or Cerambycidae, are generally rather large 

 beetles, somewhat cylindric in shape and with long antennae ; in some cases 

 they are enormously developed. The white larvae are normally legless, 

 usually rounded, and with the head only slightly flattened, and as a rule they 

 make well defined galleries more or less circular in section. This family 

 includes a large number of very destructix'e borers. 



The leaf feeders or Chrysomelidae are relatively abundant on various 

 trees, and some species are exceedingly numerous. The beetles present a 

 somewhat \ariable a|)])earance both in color and shape, and the larvae are 

 equally diverse. The latter, normally, have six legs, with rounded body, 

 and freijuently there is an anal proleg ; as a rule they are leaf fec-ders. 



The weevils or Curculionidae may be easily recognized by the distinct 

 snout and hard shell or I'xoskeleton. The wood-boring grubs belonging to 

 this family are legless, curled and thickened anteriorly, and may work 

 t:ither in Ijark or wood. 



The i)arkor wood borers, .SciWytidae, are all small species, usually some- 

 what cylindric in shape and brown or black in color. Their wood-boring 

 larvae are legless, rountl, slightly thickened anleriorl\- and frequently smaller 

 than the erubs of weevils. 



