338 BOARD OF AGRICULTURE. [Pub. Doc. 



itself at least, and will leave a more valuable stand than if it 

 had been left alone. It is also easier to cut live trees than dead 

 ones. 



4. Moth thinnings are advantageous to the owners of poor 

 or sprout growth, where there is a considerable proportion of 

 young pine present. The wood will not pay for the work, but 

 the development of pine will. If left alone, especially where 

 the growth is gray birch mixed with pine, the moths will prac- 

 tically destroy the whole value of the growth, which if properly 

 conserved would prove to be considerable. 



5. Moth thinnings are cheaper and more effective if under- 

 taken before the moth infestation becomes serious than if made 

 afterwards. 



Considerable cost data have been collected from the thinning 

 operations carried out under the direction of this department, 

 but not enough to give any certain figures as yet. The main 

 factors in the cost are the efficiency of the labor, the size and 

 thickness of the growth, the severity of the thinning, the 

 amount and method of brush-cutting and disposal, and the 

 utilization and market of the product. In general terms it 

 may be said that a thinning which will yield 7 or 8 cords to 

 the acre will pay for itself, allowing for the burning of the slash- 

 ing, provided that there is not an unusual amount of brush to 

 be cut, and that ordinary labor and market conditions prevail. 

 The cost mounts rapidly if large quantities of brush are to be 

 cut. The cheapest way of doing work is by the cord, under 

 good supervision, or an experienced crew working by the day 

 may do as well. The profits may be considerable if there are 

 many ties, poles or piles to be cut. 



Work accomplished this Year. 

 Since this work was organized a gratifying amount of interest 

 has been shown in thinning work. The work carried on has 

 not been primarily experimental in character, but rather educa- 

 tional and practical. The United States Bureau of Entomology, 

 in connection with the Forest Service, is now carrying on ex- 

 periments in moth thinnings under Mr. Clement, from which 

 we anticipate some very practical data. 



