590 



AMERICAN FORESTRY 



How Cones Are Affected. 



THESE LONGITUDINAI, AND TRANSVERSE SECTIONS OF THE SUGAR PINE CONES, NATURAL 

 SIZE, SHOW THE PRIMARY EGG GALLERIES, B-1 MADE BY THE CONE BEETLE. 



caused by the larvae of tiny wasps, 

 known as seed cholcidids. These feed 

 entirely within the inner lining of the 

 seed, which outwardly presents a nor- 

 mal appearance. Ordinarily the only 

 way to detect the damage is to cut the 

 seed open, when it will be found hollow 

 with the small, headless maggot-like 

 larvae lying in it. Fir suffers espe- 

 cially from these insects. The maggots 

 of flies and midges also cause consid- 

 erable damage to fir cones. 



In looking for evidence of the pres- 

 ence of these various pests, beetles, 

 worms, cholcidids and maggots, it is 



frequently necessary to cut open the 

 cone. The beetle, it is true, betrays it- 

 self by a small entrance hole at the base 

 of the cone, with castings or small pitch 

 tubes, during the early summer. Later 

 the cones assume a brown, withered 

 appearance. On the other hand, as has 

 already been said, there is no external 

 evidence whatsoever of the presence of 

 the seed cholcidid. The fir-cone mag- 

 got and the cone moth can best be dis- 

 covered by opening the cone, sectioning 

 it in several different ways and then 

 searching for the caterpillars or the 

 active larvae. 



