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THE POPULAR SCIENCE MONTHLY 



Fig. G. Results of crossing two Inbred Strains of Maize. At the right 

 average of the parents after three generations inbreeding, 61 bushels per acre. At 

 the left crop of first generation cross of the inbred strains, 101 bushels per acre. 



them the grower obtains two strains and plants them in alternate rows. 

 At flowering time all of the male flowers or tassels are removed from 

 one of the plants of the varieties before they shed their pollen. All the 

 ears that these plants produce are crossed with the other variety. It is 

 this seed that produces the vigorous plants. 



This method might be made the basis for some very valuable work 

 in forestry. It is quite conceivable that many important timber trees 

 might be found where nearly related species or varieties would cross 

 readily. Experiment would show how great an increase in rapidity of 

 growth could be expected., and whether such an increase would pay for 

 the increased expense of hand hybridized seed. 



Fig. 7. Silver Hill. Normal at left. Bud variation isolated by selection at 



the right. 



