206 DRY-FARMING ’ 
ditions are all favorable, seeds cannot germinate 
properly. The first requisite for successful seed 
germination is a proper degree of heat. For every 
kind of seed there is a temperature below which 
germination does not occur; another, above which it 
does not occur, and another, the best, at which, pro- 
viding the other factors are favorable, germination 
will go on most rapidly. The following table, con- 
structed by Goodale, shows the latest, highest, and 
best germination temperatures for wheat, barley, and 
corn. Other seeds germinate approximately within 
the same ranges of temperature : — 
GERMINATION TEMPERATURES (DEGREES FAHRENHEIT). 
Lowest HicHeEst Bust 
Wheat 41 108 84 
Barley 41 100 84 
Corn 49 115 91 
‘Germination occurs within the considerable range 
between the highest and lowest temperatures of this 
table, though the rapidity of germination decreases 
as the temperature recedes from the best. This ex- 
plains the early spring and late fall germination when 
the temperature is comparatively low. If the tem- 
perature falls below the lowest required for germina- 
tion, dry seeds are not injured, and even a tempera- 
ture far below the freezing point of water will not 
