152 PRACTICAL FORESTRY 
of the proper kind of fire lanes, the use of spark- 
arresters, and constant watchfulness during the dan- 
gerous season on the part of railroad employees. 
A host of fires is caused by carelessness on the part 
of campers and hunters, and by irresponsible and 
thoughtless persons. A very large number of fires is 
set accidentally by farmers in clearing land and in 
burning over meadows. Fires are often set malicious- 
ly out of revenge, or for some other ulterior motive. 
One of the most serious causes of fire, although per- 
haps not the most extensive, is the time-honored 
custom of burning over forest land for the purpose of 
improving the pasture and the blueberry crop. This 
is a legitimate cultural operation wherever the man 
who owns the property does the burning. In many 
instances the land is worth more for this purpose 
than for forest. Prof. W. M. Munson, in a valuable 
paper on The Blueberry in Maine, says: “ In the 
southeastern part of Maine, principally in Washing- 
ton County, there are about one hundred and fifty 
thousand acres known as the ‘blueberry barrens.’ 
Much of this land was burned over by the Indians 
before the colonial period, and since the timber was 
removed from the remainder, it, too, has been re- 
peatedly burned to keep down the growth of birches, 
alders, ete., and to facilitate the harvesting of the 
fruit.” He mentions one tract of forty thousand 
