796 Journal of Agricultural Research vol. vi, No. 20 



A large proportion of impermeable alfalfa, crimson-clover, okra, 

 and hairy-vetch seeds will germinate in the soil during the first few 

 months after planting, some of them early enough to be of importance 

 to the crop. 



Nearly all alfalfa and okra seeds, even if they are impermeable in 

 the fall, are killed when they pass the winter in the soil or on the plants 

 out of doors in a freezing climate. A small proportion of the impermeable 

 alfalfa seeds survive with their vitality uninjured. Some of the okra 

 seeds remain impermeable during the winter, but the majority even of 

 those which remain impermeable are killed by the winter's exposure. 



LITERATURE CITED 

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1884. The vitality of seeds buried in the soil. In 23d Ann. Rpt. State Bd. 

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1889. Vitality and growth of seeds buried in soil. In Proc. 10th Ann. Meeting 

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(7) Ewart, A. J. 



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(8) Gola, Guiseppe. 



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(9) Guppy, H. B. 



1912. Studies in Seeds and Fruits . . . 528 p. London. 



(10) Harrington, G. T. 



191 5. Hard clover seed and its treatment in hulling. U. S. Dept. Agr. Farm- 

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(11) HiLTNER, Lorenz. 



1902. Die Keimungsverhaltnisse der Leguminosensamen und ihre Beeinflus- 

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(12) Hume, A. N., and Champlin, Manley. 



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(13) MuLLER, Karl. 



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