trees, even though partly living, become weakened to such an extent that 

 they are no longer able to compete with their more vigorous neighbors. 



In drying, treated trees become stiff enough to act as props for others 

 which might be severely bent or broken bv heavy snowfall. This was ob- 

 served following an early winter storm where other trees near the treated 

 plot had been damaged while those supported by chemically killed trees 

 were unharmed. 



It takes a year or less for treated white and red pine to become bare of 

 foliage. During that time the light reaching the ground gradually increases. 

 Since no abrupt change in the canopy takes place, the remaining trees appear 

 to accommodate themselves to the changing conditions without a setback 

 which accompanies t^he usual type of thining operation where the trees are 

 felled. 



Thinning with axe or saw leaves the pine forest in a tangled inflammable 

 condition. Dry needles remain on the tops and branches for several years. 

 The chemically killed trees dry out. remain standins. and do not prevent easy 

 access throughout the stand. The increase in fire hazard is not significant. 



c 



Sample Field Results 



A 70-ACRE mixed stand of hardwoods and white pine was treated to release 

 the pine from an overstory consisting of white, red, and black oak, soft 

 maple, and other hardwoods to a lesser degree. The average canopy height of 

 the hardwoods overtopping pine was 30 feet and the pine understory 10 to 

 ]5 feet. Sample counts showed a distribution of about 400 hardwoods and 

 600 white pine trees per acre. The average diameter of hardwoods at breast 

 height was four inches. 



The decision to destroy hardwoods in favor of pine was due to the low 

 quality of the hardwoods. There was little prospect of developing a hardwood 

 stand of even moderate value without radically altering its composition 



The chemical treatment was done by a four-man crew working between 

 brushed out property lines. Each man was equipped with a carpenter's apron 

 holding several hundred treated tabs and a treating tool or spud. 



Rubber gloves, which were tried for a few days, were discarded as the 

 men complained of discomfort due to excessive hand perspiring. A pro- 

 tective hand cream proved to be a satisfactory substitute for gloves with 

 no complaints about its use. 



Crew members received about a half hour of instruction following which 

 they carried on with one man acting as a working foreman. He assisted in 

 keeping the line of progress straight and made decisions relative to skipping 

 small areas containing insufficient pine to warrant treatment of the hardwoods. 



Most of the trees were treated with one tab. The larger ones required 

 two or more, according to diameter and size of crown. 



Observations 



Color change, accompanied by some wilting, was observed after 48 hours. 

 After six days treated trees showed browning of the foliage over the treated 

 area. 



Light at the ground was more than doubled six weeks after the work was 

 done. 



10 



