﻿NORMAL DAYS WORK FOR VARIOUS FARM OPERATIONS. 6 



be obtained. From such data the principles and relationships for 

 wise investment can be worked out, which might possibly be recog- 

 nized by the occasional individual, but which must at best be appre- 

 hended only vaguely by the majority, if they are not quite without 

 the purview of the man confined to the duties and experience of one 

 farm. 



SEASONAL OPERATING FACTORS. 



Under practical farm conditions, work can be planned intelligently 

 and successfully executed only when allowance is made for rainy 

 days and other climatic conditions which interrupt the various opera- 

 tions in their respective seasons. Conclusive data of this character 

 for any region can be secured only by long-continued observations of 

 the weather in connection with its interfering effect on farm work. 

 However, approximate seasonal factors for farm operations can often 

 be calculated for any locality from the current practice with any 

 crop. 1 



i In the southern part of the corn belt one man with a 2-horse team can plow, harrow three times, and 

 plant 40 acres in corn from about March 10 to May 10. What fraction of this period is available for field 

 work? 



A man can plow 1.75 acres, harrow 10 acres, or plant 11 acres per day. Hence, to plow, harrow three 

 times, and plant 1 acre will require — 



(r75 + 10 + ri) day ' T ° d ° 40 aCreS wil1 re 1 uire 40 \T1E + W + V[) days - 



Another expression for this number of days may be found as follows: The whole number of days from 

 March 10 to May 10 is 61; if F represents the fraction of this period available for field work, then FX61 is 

 the number of available days. Thus, we have two expressions for the number of days available for field 

 work, and these two expressions may therefore be equated. This gives us the equation — 



40 (i J 75+i0 + il) = F X 6L 



Solving this equation, we find F equals 0.631. That is, 63.1 per cent of the period is available for field 

 work. 

 The following more general formula, based on the above considerations, is useful in many ways: 



/t t' t" \ 



In this formula A stands for the number of acres of land involved; t, t', t", etc., represent the number of 

 times the various operations are performed; a, b, c, etc., represent the area covered in a day in each of the 

 various operations performed; F is the fraction of time available for field work; and S is the number of 

 days in the season during which the work must be done. 



Another use to which this formula may be put is illustrated in the following problem: Assuming that 

 during March one day in two is available; during April and May, two days in three; that oat land is 

 plowed, harrowed once, and drilled; that corn land is plowed, harrowed three times, and planted; that 

 a day's work is plowing 1.75 acres, harrowing 10 acres, drilling 8 acres, or planting 11 acres of corn; and 

 that the rotation used calls for equal areas of corn and oats; what area of each of these two crops can one 

 man put in between March 1 and May 10? Our formula now becomes— 



/l 1 1\ , / 1 3 1\ 1 2 



(LTS+IO+i) +A (iT75+10 + n) =2>< 31 +3 X40 - 



From this we find A equals 24 acres. That is, one man can plant 24 acres each of corn and oats. 



If in the foregoing problem we omit the plowing and harrowing for the oats and simply drill them in 

 the old corn stubble by means of a disk drill, as many farmers do, how many acres can the man put in of 

 each of these crops? For this problem the formula now becomes — 



A (?) + A (rrs+fo+n) 4x3i+?x4o. 



