The adaptation of corn to climate
1935
Jones, D.F. | Huntington, E.
Recent investigations demand a revision of the prevalent idea that seed corn brought from a distance will not produce so abundantly as local varieties. It has been widely recognized that a change in latitude brings about a marked difference in vegetative growth and time of ripening because of the alteration in the relative length of day and night. The assumption has been that this change generally works adversely. It has also been assumed that a change in longitude, since it does not alter the length of the period of daylight, produces little effect except when it means a change to deficient summer rain. Nevertheless, the prevalent opinion throughout the principal corn-growing states has been that when seed is planted at distances of more than a few hundred miles east or west of where it was grown it will not do so well as varieties which have long been grown locally.
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