SEED-TESTING. II 



"The table indicates that actual planting in the field 

 gives fewer germinations than carefnl tests in conditions 

 under control. This difference in total of germination, 

 even under favorable conditions of planting, may amount 

 to over 50 per cent. 



" In planting, due allowance should be made for the 

 comparatively bungling methods of field practice by the 

 use of greater quantities of seeds than would seem, from 

 the results of tests, to be sufficient." 



Probably the most truthful test of seeds can be made in 

 soil in earthen pans in a greenhouse or forcing-house. When 

 one desires to show the ultimate percentage of seeds which 

 contain life, the sprouting test should be used. In this case, 

 some apparatus should be employed in which the moisture 

 and temperature can be controlled to a nicety, and in which 

 the seeds can be examined as often as desired. As soon as 

 a seed sprouts, it is removed and counted as viable, wholly 

 independently of whether it is strong enough to make a plant 

 under ordinary conditions. In other words, the sprouting 

 test is almost wholly an attempt to arrive at a numerical 

 estimate of the viability of the sample, rather than an effort 

 to determine the relative strength of germinative power. 



There are many excellent devices for the making of 

 sprouting tests, only three or four of which need be men- 

 tioned here, for the purpose of illustrating some of the 

 principles which are employed. ■ One of the best known 

 of these apparatus in this country is the Geneva tester, 

 which originated at the New York Experiment Station at 

 Geneva. 



A full account of this device by Professor J. C. Arthur 

 (Botanical Gazette, 1S85, p. 425) is here inserted : 



"Various methods have been used for testing the per 

 cent and time of seed germination. Those most commonly 

 adopted in this country and also abroad have been to place 

 the seeds on the surface of porous tile, smooth sand or 

 compacted earth. Without stopping to point out the defects 

 and inconveniences of these methods, I desire to describe 



