102 PRINCIPLES OF PLANT CULTURE 



seeds, that may destroy the embryo. Damp seeds are also 

 hable to be destroyed by freezing. It is important that 

 seeds be dried promptly after gathering, for if mold once 

 starts, subsequent drying may not destroy the fungus; 

 the latter may resume growth as soon as the seed is planted, 

 thus enfeebling or destroying the embryo before it has 

 time to germinate. Drying by moderate artificial heat 

 (not higher than 100° F.) is wise with seeds gathered in 

 cold or damp weather. 



Seeds are shorter-lived in warm than in cooler climates. 



The most satisfactory method of preserving most seeds 

 in quantity is to inclose them in bags of rather loose texture 

 and of moderate size, and to store them in a dry and airy 

 place. 



167. Age of seed as affecting the resulting crop. — 

 Seeds grown the same or the preceding season produce, as 

 a rule, more vigorous plants than older seeds. They 

 may not, however, in all cases produce plants that are 

 most productive of fruit or seed, for excessive vigor is 

 generally opposed to reproduction. Cucumber and melon 

 plants grown from seed three or four years old are often 

 more fruitful than those from fresh seeds. In crops grown 

 for parts other than fruit or seed, fresh seeds are un- 

 doubtedly preferable, but in crops grown for seed or 

 fruit, fresh seed may not always give as large returns as 

 seed of some age. This subject needs further investiga- 

 tion. 



168. Effect of drying on the vitality of seeds. — The vigor 

 of seeds is probably never increased by drying them, but 

 the seeds of most annual and biennial plants may become 

 air-dry without material loss of vitality. The seeds of 

 many shrubs and trees, however, lose vitality rapidly 

 by such drying and those of some species are destroyed 



