PROPAGATION BY MEANS OF SEEDS AND SPORES 25 



will sprout when not strong enough to germinate completely, 

 and more seeds will be counted as viable when they are tested 

 in a germinating apparatus where the conditions are perfect 

 - than when they are normally planted in the earth. There 

 is even sometimes a marked difference between the results of 

 seed-tests in earth in the greenhouse and in outdoor planting, 

 as the following comparisons (Bulletin 7, Cornell Experiment 

 Station, 1889) plainly show : 



"It has been said recently that the ideal test of seeds is 

 actual sowing in the field, inasmuch as the ultimate value of 

 the seed is its capability to produce a crop. This notion of 

 seed-tests is obviously fallacious, although the statement on 

 which it is based is true. In other words, actual planting 

 rarely gives a true measure of the capabilities of all the seeds 

 of any sample, because of the impossibility to control con- 

 ditions and methods in the field. The object of seed-tests is 

 to determine how many seeds are viable, and what is their 

 relative vigor; if planting show-s poorer results, because of 

 covering too deep or too shallow, by exposing to great extremes 

 of temperature or moisture, or a score of other untoward con- 

 ditions, the sample cannot be held to account for the short- 

 coming. The table on page 26 indicates the extent of varia- 

 tions that may be expected between tests and actual plantings 

 of seeds from the same samples. 



"Various samples were tested indoors and actually planted 

 in the field. The seeds were sown in the field June 5, and the 

 last notes were taken from them July 5. They were sown on 

 a gravelly knoll. Rain fell about every alternate day, and the 

 soil was in good condition for germination throughout the 

 month. The indoor tests were made in loose potting earth, 

 or in sand in seed-pans. 



"The table indicates that actual planting in the field gives 

 fewer germinations than careful tests in conditions under 

 control. This difference in total of germination, even under 



