11 



shaking in a bag until thoroughly dry, because if moisture r3mains 

 unevaporatecl it is apt to form mildew when the nuts are prematurely 

 packed for shipment. 



Nuts for planting should not be scalded, and care should be taken 

 not to cook the kernels of nuts intended for sale. Some growers 

 claim that the hot-water treatment is objectionable because the nut- 

 shells lose a certain degree of polish, rendering them less desirable 

 for market. 



Heat. — Infested nuts can be subjected to a -temperature of l)e- 

 tween 12.5° F. and 150° F. without injuring them for food or for 

 seed, and this will effect the destruction of the larvae within. Some 

 growers of chestnuts destroy the w^eevils by kiln-drying. 



Cold storage. — Cold storage has been employed and is successful 

 in arresting the development of the larva?. The appearance of the 

 nuts is scarcely different from that of those not so stored, but nuts 

 thus treated and submitted to the writer after becoming dry were 

 deficient in flavor, having an acrid and moldy taste. 



A crude form of cold storage has been successfully followed by a 

 Virginia grower. It consists in placing nuts in the earth under the 

 shade afforded by his house, where the soil temperature, after the 

 nuts are gathered, does not exceed 50°. Since most insects are inac- 

 tive below 51° this has the effect of restraining their development, 

 causing the eggs or minute larva^ to die. 



Preventives. 



Choice of location for the orchard. — The selection for the 

 planting or grafting of chestnuts of a locality with reference to the 

 chances of immunity from injury by nut weevils is a matter of great 

 importance. For this reason it is most undesirable to plant in the 

 immediate vicinity of woodland abounding in wild chestnut and chin- 

 quapin, since these trees furnish natural breeding places for the in- 

 sects, and are, therefore, a constant menace to successful chestnut 

 culture. Too frequently growers suffer losses from weevils because 

 they neglect to gather the wild chestnuts or chinquapins in the im- 

 mediate vicinity of their cultivated groves. Another phase of bad 

 management which is frequently practiced is the grafting of culti- 

 vated varieties on native chestnuts growing in rocky and uneven soil, 

 often on hillsides, as shown in figure 11. In such places it is impos- 

 sible to harvest a complete crop, and, what is of equal importance, to 

 gather the remnants. Hence, to secure these results, it is impera- 

 tive to plant or graft trees on smooth ground (fig. 12), first for the 

 sake of economy, and second to permit the collection of all of the 

 nuts, leaving none for the propagation of weevils. It is also neces- 

 sary to keep the soil clean of herbage, as shown at the left of fig- 

 ure 12— not overgrown with brush, as illustrated at the right. 



[Cir. 99] 



