FOREST TREE SEED AND SEED COLLECTING 103 



conifers, the color of the seed indicates ripeness. In the latter 

 case, it is often desirable to begin gathering the fruits while they 

 appear green because, if delayed too long or until they begin to 

 change color, a large part of the seed is lost in the harvesting. 



Seed gathered before maturity is light in weight and after stor- 

 age the kernel becomes more or less shriveled. Past experience 

 in this country indicates that seed collecting is begun too late 

 rather than too early, particularly in the case of coniferous seed, 

 and that there is a large loss caused by the seed dropping from 

 the cones before or during the process of collecting. 



Germinative energy is greatest in most seeds shortly after they 

 mature. Some seeds, however, appear to require a more or less 

 extended period of rest before germination will take place. After 

 the usual time for germination passes, the vitality decreases with 

 age. The rate of decrease depends very largely upon the species 

 and the conditions under which the seed is stored. When pos- 

 sible to obtain fresh seed it should always be used. When it is neces- 

 sary to use old seed germination tests should be made immediately 

 before the seed is sown. 



11. THE Loss THROUGH STORAGE 



The loss through storage is very largely dependent upon the 

 temperature and moisture conditions under which the seed is 

 stored. From his own experiments, the author believes that, 

 if temperature and moisture are properly regulated, 1 even the 

 most sensitive seed can be kept in dormant condition for many 

 months without serious loss in viability. Under natural condi- 

 tions, when the requirements for germination are absent, the seeds 

 of poplars, willows, white elm, red maple, and silver maple remain 

 alive but a few weeks after ripening. It is customary to plant the 

 seed of these species immediately after ripening, which in southern 

 New England is usually the first week in June. All species which 

 mature their seed in late spring or early summer should be sown 

 immediately after the seed matures. 



1 The author has succeeded in storing the seed of white elm, red maple, and 

 silver maple for one year. On June 2, 1905, a quantity of the seed of each 

 of these species was gathered at New Haven, Conn., and spread out in the 

 shade until somewhat shrivelled and too dry for germination. On June 10 the 

 seed was placed in a box with alternate layers of dry sand. The box was 

 buried in the soil to a depth of 2 feet under the protection of a building. 

 On April 25, the following spring, the box was removed and the seeds found to 

 be in good condition, many of them having already begun to germinate. 



