242 AMERICAN FORESTRY 



lono- is to be calculated, the width, D between outside rows of the belt must be 



(D + CFXHX|)X5280 

 added and the formula becomes A= 4 356 o 



Calculations of the market values of the timber were based upon stumpage 

 prices of $10.00 per thousand board feet for saw logs and $2.00 per cord for 

 firewood. Fence posts were valued at 5cts. to 24cts. each according to kind 

 and quality. The prices allotted to fence posts are conservative except for 

 cottonwood and soft maple which are practically worthless for posts and 

 rarely used for such purposes. The computations show that cottonwood 10 to 

 40 years old is capable of producing values of $1.26 to $5.39 per acre per 

 annum in lumber and fuel, reckoning interest at 4 per cent per annum. A 

 single row one mile long of cottonwood trees oriented north and south and 40 

 years old was worth $3,270. Another row of the same age oriented east and 

 west was worth $2,296 per mile. The values of the north-south rows is 

 strikingly greater than those of the east-west rows, but when reduced to acre- 

 age values the difference disappears, because the north-south rows damage 

 much wider strips of land than the east-west rows. The measurements show 

 that cottonwood begins to mature into saw-log size at a very early date, one 

 plantation having produced 4,300 board feet per acre when twenty years old. 



THE GROWTH AND YIELD 



Equally interesting facts are brought out with reference to the growth 

 and yield of green ash, silver maple, honey locust, white willow, Russian mul- 

 berry, and Osage orange. The great value of Osage orange and mulberry in 

 hedges is realized when we learn from this bulletin that four different hedges 

 of the former species ranging from 20 to 31 years old were each worth over 

 $1,000 per mile, and that two mulberry hedges 11 and 12 years old respectively 

 were each also worth more than $1,000 per mile. The annual acreage values 

 of the Osage orange plantations ranged from $1.18 to $12.51, while one mul- 

 berry plantation earned as much as $32.75 per acre per annum, allowing in- 

 terest at 4 per cent. 



Catalpa is not suitable for windbreak plantations because of its sus- 

 ceptibility to damage from wind and drouth. White pine and Scotch pine are 

 very promising trees for windbreaks in the Lake States and the Middle West. 



The last ten pages of the bulletin are devoted to a discussion of methods 

 and plans for the establishment and management of efficient windbreaks. 

 The protection afforded by an Osage orange hedge on the average is equivalent 

 to the yield of a strip twice as wide as the height of the trees, while the 

 protection afforded by the most efficient grove is equivalent to the yield of a 

 strip three times as wide as the height of the trees. "This means that the 

 farmer in the Middle West can afford to maintain a windbreak running 

 through the farm from east to west, and having a width of 240 feet in the case 

 of mature cottonwoods 80 feet high," (page 90). Such a grove will occupy 

 approximately 15 acres on a quarter section ; but two such belts of timber are 

 required for the efficient protection of 160 acres. Such windbreaks will pay 

 a rental in protection equivalent to the grain that would grow on the land 



