12 



calculating, and should then use the measure thus determined 

 upon unless for some special reason it is desirable to use some other 

 measure in a particular tabulation. The following paragraphs 

 state the conditions under which each of these measures may be 

 used: 



a. Size of farm in acres. The size of the farm in acres may be 

 used where the type of farming is similar on all the farms, or nearly 

 all of them, provided the proportion of land occupied by timber 

 and by land devoted to pasture does not vary widely from farm 

 to farm. In other words, in a locality where the farms are quite 

 uniform in character, with about the same proportion of crop land, 

 pasture land, and timber land, and with similar intensity of live- 

 stock enterprises, the size of the farm is a satisfactory measure of 

 the magnitude of the farm business. Where it can be used it is 

 by far the simplest measure; but there are relatively few areas 

 where such a measure is accurate. 



b. Crop area equivalent. Where the type of farming is simi- 

 lar on the different farms but the proportion of pasture land and 

 of woodland is highly variable, a very accurate measure of magni- 

 tude of business is the sum of the crop area and the crop area equiva- 

 lent of the pasture area, which sum we may call the crop area 

 equivalent of the farm. It is applicable in all cases where the type 

 of farming is of approximately similar degree of intensity on the 

 different farms. In order to reduce the pasture area to its equiva- 

 lent crop area we have the following considerations: 



We may assume that 30 pounds of dry hay per day is the daily 

 ration for a mature animal and that the number of acres of pasture 

 required to carry one mature animal during the pasture season 

 will furnish the equivalent of this much hay. Let C represent 

 the acres of pasture required to furnish this much feed daily. If 

 the pasture season is 5 months, or 150 days, long it must furnish 

 during the season the equivalent of 150 times 30 pounds of hay, 

 which is 2 1 tons. Let T represent the average yield of hay in tons 

 per acre on the farm in question. We then have C acres of pasture 

 furnishes the equivalent of 2^ tons of hay; C acres of pasture are 



24- 2 



equivalent to qr acres of hay; 1 acre of pasture is equivalent to 





acres of hay; P acres of pasture are equivalent to -^ acres of hay, 



where P is the total acres of pasture on the farm. Thus, to find the 

 number of acres of hay to which the pasture on the farm is equiva- 

 lent, multiply the number of acres of pasture by 2\ and divide 

 the product by the carrying capacity of the pasture (acres per 

 animal) multiplied by the average yield of hay in tons per acre. 



