46 MISSOURI AGR. EXP. STA. RESEARCH BULLETIN NO. 17 



than 900 separate plantings so that these investigations alone repre- 

 sented a total planting and study of nearly 100,000 seeds. 



EXPERIMENT 1 



During the summer of 1911 the collection of seeds from 

 wild and cultivated plants amounted to 122 species. These were 

 harvested as nearly as possible immediately after ripening. From each 

 species 200 seeds were counted out. One-half of each sample was 

 planted at once in moist sand, and the other half dried at room tem- 

 perature for one month before planting. 



Results from Experiment 1. Up to October 15, when observations 

 ceased, 23.1 per cent of the species had germinated in less than two 

 weeks, 19.8 per cent after two weeks, and 57.1 per cent did not grow 

 at all. The seeds planted at maturity, on the average, germinated in 

 22.2 days while the dried seeds required only 17.8 days. The total 

 germination in the mature seeds was 33.3 per cent, dried seeds 40.9 per 

 cent. 



Conclusions. If two weeks is sufficient time to allow seeds for 

 making "immediate" germination, then it must be concluded that fully 

 75 per cent of the species in the experiment have a rest period. Also 

 the usual assumption that seeds which fail to grow immediately after 

 maturity are possessed of a rest period apparently is incorrect, as the 

 rest period may not set in at any time during several days after ripen- 

 ing. Finally, seeds dried for a month germinate quicker and better 

 than when planted immediately after maturity, thus showing that the 

 majority of seeds are greatly benefited by being allowed to pass thru 

 a period of dormancy before being planted. 



EXPERIMENT 2 



The seed collection of 1912 was intended to be quite 

 complete for the entire season. However, the plans could not 

 be carried out on account of illness. Collecting stopped July 20. 

 Seeds were again gathered as near maturity as possible. One lot was 

 planted at once, while a similar lot (set not complete) was dried out 

 before planting. 



Results from Experiment 2. The dried seeds gave approximately 

 the same results as in the previous years' test, viz., that they germinated 

 more quickly and better than those that were planted at once after 

 maturity. The set of seeds planted immediately after ripening con- 

 sisted of seventy-six species, representing thirty-two orders. Of 

 these, 23.6 per cent grew in less than three weeks, 39.4 per cent in fall 

 or the following spring, and 37 per cent did not grow at all. 



