PLUM INSECTS 247 



About 28 days, on an average, after entering the ground the 

 beetles emerge, })ut not all this time is passed as a pupa; 12 

 to 16 days are spent in the soil befon* pupation, and after the 

 transformation to the adult it takes s(;veral days for the beetle 

 to become hardened enough to work its way to the surface. 

 These bcu'tles of the new generation do not as a rule lay eggs 

 th(^ same season, but after fcnxling greedily on the fruit (Fig. 223) 

 for som(^ time seek hibernating quarters on the approach of 

 cold weather. In the North, the damages done by these new 

 beetles may be very great, especially on plums and apples, but 

 in the South, where early maturing varieties 

 are grown, it is of less importance. 



Methods of control. 



Curculios thrive in neglected, over-grown, 

 unpruned and uncultivated orchards sur- 

 roun(l(>d by stones walls or neglected hedges 

 and situated near pieces of woodland. The 

 first step towards their control consists in 

 correciting as far as possible all these con- 

 ditions at variance with the best horti- Fkj. 224. — Plum 

 cultund prafti.,.. HilHTnating shclfr sl,„ul.l IXi'l^^.^HoTniu;;: 

 be reduced to a minimum by th(^ removal of 

 all stone walls and stone piles, by the cleaning up of over- 

 grown hedges and fences and by th(^ destruction of all trash 

 under which the beetles might find shelter. The trees should 

 be properly pruned to admit the sun, for curculios are shy 

 creatures, preferring the dvvp shade for their work, and 

 furthermore it has been shown in Illinois that direct sunlight 

 striking the fallen fruit is soon fatal to the grubs within. Where 

 the trees are large and the ground is k(>pt smooth and free from 

 weeds, it is worth while to rake the fallen fruits out into the open 

 where the sun can strike them. In doing this the small early 

 drops should not be neglected, for a large percentage of the 

 grubs develop in fruit not mu(;h larger than peas. 



