326 INSECTS AFFECTING VEGETATION 



MANUFACTURED PRODUCTS. 



Freshly sawed hardwood lumber placed in close piles during 

 warm, damp weather in the period from July to September, inclusive, 

 presents the most favorable conditions for injury by ambrosia bee- 

 tles. In all cases it is the moist condition and retarded drying of the 

 lumber which induces attack. Therefore any method which will 

 provide for the rapid drying of the lumber before or after piling will 

 tend to prevent loss. It is important, also, that heavy lumber should, 

 as far as possible, be cut only in the winter and piled so that it will 

 be w r ell dried out before the middle of March. 



The damage to lumber and square timber when the bark is left 

 on the edges or sides can be prevented by removing the bark before 

 or immediately after the lumber is sawed, or by sawing and piling 

 the material during the winter, or if sawed at other times it should be 

 piled so that rapid drying will be facilitated. 



SEASONED PRODUCTS. 



Unfinished Seasoned Products. Injury by powder-post beetles 

 to dry hardwood lumber and other material in stacks or storehouses 

 can be prevented as follows : 



(1) Have a general inspection of the material in the yards and 

 storehouses at least once a year, preferably during November or 

 February, for the purpose of (a) sorting out and destroying or other- 

 wise disposing of any material that shows the slightest evidence of 

 injury, as indicated by the presence of fine powdery boring dust, 

 and (6) sorting out and destroying all old and useless sapwood ma- 

 terial of any kind that will offer favorable breeding places for the 

 insects. 



(2) Prevent the introduction into the lumber yards or store- 

 houses of any infested material, remembering that the insect may be 

 thus distributed to or from all parts of the world. 



(3) Adopt a system of classification of all dry or seasoned hard- 

 wood stock which will provide for (a) the separation of the pure, 

 heartwood material from the pure and part sapwood material; (6) 

 classification of all kinds of wood most liable to attack, such as hick- 

 ory, ash, oak; (c) the successive utilization or sale of the older mate- 

 rial (remembering that material one year old or over is far more 

 liable to injury) ; (d) providing against the accumulation of refuse 

 material in which the insects could breed; and (e) treating the best 

 material with linseed oil or kerosene to prevent attack. 



Finished Seasoned Products. Damage to finished handles, oars, 

 spokes, rims, hubs, wheels, and other unpainted wagon, carriage, 

 machinery and implement stock in factories, wholesale and retail 

 storehouses, and army and navy stores can be prevented by the adop- 

 tion of the same general rules as those given under rougn products. 

 In addition, damage can be controlled and prevented in the follow- 

 ing manner: 



Sort out and (a) destroy all articles showing the slightest evi- 

 dence of powder-post injury, or (>) treat with kerosene oil such in- 

 fested and slightly injured articles as may be tested for required 

 strength and found to be of sufficient value for retention, placing the 



