1918.] FIELD CROPS. 739 



hills containing plants from botti Maryland and Arizona grown seed. In 1915 

 the crosses were made by hand instead of by detasseling alternate rows as in 

 1912. 



In spite of all precautions a certain measure of selection was thought to pre- 

 vail, but it is concluded that " the entire effect of selection would be to favor 

 the home-grown seed, and that the transferred seed was not superior to the 

 home grown in every instance may not be held to vitiate the cases in which 

 significant differences in favor of the transferred seed were observed. The 

 results indicate, however, that the stimulation is more pronounced in some 

 stocks than in others. Thus, in the 1916 comparisons Boone X Hickory King 

 stands out as a conspicuous exception. In all other stocks the transferred seed 

 produced taller plants than the home-grown seed; but with Boone X Hickory 

 King, the home-grown seed exceeded the transferred by 6.2 per cent, a difference 

 not to be ascribed to chance, being more than eight times the probable error. 

 Of the three stocks in which the yield was taken, Boone X Hickory King is also 

 the only one to show superiority for the home-grown seed. Taken alone, the 

 differences in yield could not be considered significant, but the agreement with 

 the results for height confirms the reliability of these results." 



The investigations are held to indicate the existence of a hitherto neglected 

 factor in maize production, but much more extensive experiments are deemed 

 necessary to determine its extent and practical importance. The experimental 

 work reported is summarized as follows : " Hybrids between the same pairs 

 of varieties made at different localities showed no decrease in yield as a result 

 of transferring the first-generation seed to a new locality. On the contrary, 

 the change of environment seemed to act as a stimulus, with the result that the 

 yields were increased in all but one of the hybrids tested. One unhybridlzed 

 variety was included in the experiment, and this also gave slightly increased 

 yields as a result of being transferred to a new environment. In 6 of the 10 

 comparisons the increase is too large to be ascribed to experimental error and 

 indicates that new-place effect should be taken into consideration as a factor 

 of production. . . . 



" There is no evidence that the importance of using acclimatized seed has been 

 overestimated. On the contrary, the experiments show that new-place effect 

 may often obscure the differences between acclimatized and unacclimatized 

 seed when first compared, and thus interfere with a full appreciation of the 

 value of adaptation. . . . The results also indicate that adaptation in maize 

 comes about through selection rather than as a direct reaction to the environ- 

 mental conditions." 



Observations regarding the corn crop of 1917 {AIo. Bui. Ohio Sta., 3 {1918), 

 No. 1, p. 26). — The results obtained with corn in five- and three-year rotations 

 at Wooster (Ohio) under various fertilizer and manure treatments are briefly 

 reviewed. 



Grown continuously without fertilizer, corn yielded but 9.67 bu. per acre, 

 while in a rotation of corn, oats, wheat, clover, and timothy it produced 30.28 

 bu. With applications of 12.5 and 25 tons of manure per acre in five years, 

 corn grown continuously gave yields of 19.2 and 33.3 bu. per acre, respectively, 

 while with an application of 16 tons in a five-year rotation it produced 75.36 bu. 



Approximately 55 per cent of the Ohio corn crop is said to have fully ma- 

 tured in 1917, only about one-fourth being fit for seed and 39 per cent being 

 described as soft and unmerchantable. 



Selecting' and testing seed corn, C. W. Goodman (Texas Dept. Agr. Bui. 53 

 (J9i7), pp. 23, fi[ts. 10). — Detailed dii'ections are given for the selection and 

 testing of seed corn. 



62077°— 18 4 



