428 FARMERS' INSTITUTES. 



Tomato seeds 12 years old have tested as high as 98%. 

 Squash " 14 " " " " " " " 60%. 

 Beet " 15 " " " " " " " 50%. 



Many seeds have even greater vitality than this. DeCandolle mentions a 

 number of species which germinated when fifteen years old, nearly all belong- 

 ing to the Leguminosge or Malvaceae. About twenty have been found to 

 germinate when twenty to thirty years old, and Colutea and Coronilla still 

 retained life when forty years old. Seeds of Nelumbium and Datura are 

 said to have sprouted when more than one hundred years old. DeCandolle 

 speaks of Nelumbium speciosum seeds over one hundred and fifty years old 

 that sprouted. 



Some fifty years ago the story started that wheat from the wrappings of 

 the Egyptian mummies, two thousand or more years old, had been made to 

 germinate, but the statement is no longer accepted. 



Seeds, deeply buried in the soil, are often capable of germinating after a 

 long series of years has elapsed. When deep enough to be away from the 

 influence of the air and kept at a low temperature, the presence of moisture 

 does not seem to be injurious, and many seeds germinate after having been 

 buried forty or fifty years. A few years ago Dr. Beal found that a large 

 per cent of the seeds of some of our worst weeds, that had been buried in 

 bottles in a sandy knoll for five years, germinated, and it is possible that 

 many others, of which the seed coats alone remained, had sprouted while 

 still in the soil. 



When seeds are exposed to moisture and the air at certain temperatures, 

 a process known as germination takes place. There is a wide range of tem- 

 perature at which seeds germinate ; some will throw out their radicles when 

 at or slightly above the freezing point, while others require more than 100°. 



There is, for all seeds, an optimum temperature which favors germination, 

 being, in the cases of wheat, barley and rye, from 75° to 85°, and for corn, 

 beans and squashes, from 85° to 95°. 



The temperature has a marked effect on the time required for germina- 

 tion. Thus, while rye is four days in germinating at 41°, it requires only 

 two days when exposed to a temperature of 51°. Indian corn requires a 

 slightly higher temperature, but the effect is the same. 



At 60° corn begins to germinate in 144 hours. 



a rtrio <e (i 4< a te gg c< 



a o<7° a it i( it ec /J.g (( 



t( 07° <( << << " " 48 (i 



a ii2° *' '• " ie <( 80 " 



Willow seeds push forth their radicles in a few hours, but most seeds 

 require several days, while some kinds of tree seeds do not germinate until 

 the second year. 



The first step in the process of germination is the absorption of water by 

 the seed, causing it to swell and often to burst its coverings. The common 

 cereals absorb from 40 to 50 per cent, beans and peas 100 to 115 per cent, 

 and clover 125 per cent of its weight of water. This absorption causes a 

 slight rise in temperature of the seed. 



The contents of the endosperm must be in a soluble form before they can 

 be utilized by the embryo. The sugars are already soluble, but the oils and 

 starch must be transformed into soluble carbhydrates. 



