POWDER-POST DAMAGE BY LYCTUS BEETLES. 15 



in the dead wood of natural growth of osage orange, sassafras, 

 and fig. 



Adults of the velvety Lyctus are active from the middle of March 

 till the last of August at Washington, D. C. General emergence 

 occurs from June to the last of July. 



THE WESTERN LYCTUS.i 



The western Lyctus is a rusty red-brown, slender beetle, somewhat 

 flattened and elongate, and from about one-seventh to about one- 

 fifth inch in length ; the punctures on the wdng covers are very fine 

 and placed in more or less distinct double rows. 



This species is recorded from California in commercial products, 

 seasoned orange wood and hickory, tanbark oak, and cordwood of 

 live oak. 



Adults of this species are active from April till the middle, of 

 September. 



CONDITIONS FAVORABLE FOR ATTACK. 



Second-growth white wood or sapwood of the finest quality of 

 hardwoods, especially hickory, ash, and oak, which has been stored or 

 piled in one place for two or three years or longer is especially liable 

 to damage by Lyctus beetles. This is particularly the case if the 

 material has not been handled or moved and if the old stock is 

 allowed to accumulate. Refuse and useless sapwood material and 

 infested stock piled about the sheds or yards, sapwood piling sticks, 

 etc., are sources of infestation. If the different species of hardwoods 

 are not placed in separate piles, the species of w^oods not so liable 

 to attack often become infested. 



CONDITIONS UNFAVORABLE FOR ATTACK. 



Material of species other than hickory, ash, and oak is less liable 

 to attack. Sapwood seasoned for less than 8 to 10 months w ill not 

 be attacked, and heartwood is never attached^ (fig. 12). 



The conditions wall be rendered very unfavorable for attack by 

 powder-post beetles wherever hardwood stock in yards and store- 

 houses is handled as follows: Material inspected and rehandled an- 

 nually, preferably in November and February, and that showing 

 evidence of powder-post attack sorted out and burned; all refuse 

 and useless sapW'Ood material burned; as far as practicable, all dry 

 or seasoned hardwood stock separated into heartwood, pure sapwood, 

 and part sapwood, and into hickory, ash, oak, etc., and classified ac- 

 cording to the number of years it has been seasoned, and the oldest 



^ Lycttis cavicolUs Lpc. 



2 Exhaustive strength tests conducted by tlic Forest Service show that the heaviest, and 

 consequently the strongest, hickory avcrasres liclow 10 rings per inch in rate of growth, and 

 that, weight for weight, red hickory (heartwood) is as strong as white hickory (sapwood). 



