PROBLEM 156 179 



Observations. Compare several ears of corn and select the 

 ear which has most even rows, largest kernels, etc. Suppose this 

 ear came from a plant which had but few ears. Would you select 

 for planting, ears from this plant or ears which were not quite so 

 perfect from a plant with more ears? 



Conclusion. In selecting seed for planting, what are some of 

 the factors to be kept in mind? 



Problem 155: A practical result of selection. 



NOTE. In a government test of corn to increase the yield, ears were chosen 

 from plants that gave a high yield and the seed planted in rows. Next year seed 

 from these rows was planted in rows alternating with seed from equally good-look- 

 ing ears from the -same kind of corn grown in the field. Note the results with 

 eight pairs of ears. 



POUNDS OF CORN YIELDED BY THE SEED OF ONE EAB 



FIELD EARS EARS FROM HIGH-YIELDING PARENTS 



170 Ibs. 177.5 Ibs. 



139.5 



139 



173 



154 



133 



156.5 



153 



180 

 199 

 197 

 172 

 176 

 194 

 200.5 



Observations. What per cent of increase was there from the 

 selected corn? 



If the seed from the field-grown corn yielded 42 bushels per 

 acre, what would have been the gain per acre by planting seed 

 from the selected corn? 



Conclusion. State results both in bushels and in dollars, corn 

 being worth 75 cents per bushel. 



Problem 156: To determine some means of selection of fruit 

 trees from the economic standpoint. 



Method and Observations. Given an area 1000 feet long and 

 500 wide, which might be planted as follows : 



(1) Trees 20 feet apart, bear after five years, average five hun- 

 dred apples per tree, continue bearing twenty-five years. Apples 

 wholesale $1 per hundred. 



(2) Trees 22 feet apart, bear after seven years, average six 



