CHAPTER VI 
GERMINATION OF SEEDS: SEEDLINGS 
Nature of Germination and Factors upon which it Depends 
Although the resting condition is very essential to the preser- 
vation of the life of the seed during transportation and while 
awaiting favorable conditions for germina ion, it must be aban- 
doned at some time in order that the embryo may develop into 
the plant, the production of which is the seed’s chief function. 
By germination of a seed is meant that awakening from the rest- 
ing condition in which the young plant shows practically no 
signs of life to a state of active growth. The term germination 
is used in different ways, being used to designate the beginning 
growth of such structures as a pollen tube, fertilized egg, and 
spore, but in each case, however, it refers to the initial growth. 
Seeds are considered germinated when the radicle and plumule 
have broken through and project beyond the seed coverings, 
although germination is not complete until the little plant is able 
to live independently of the stored food of the seed. 
Conditions Necessary for Germination. — The awakening of 
the seed into active growth depends upon the presence of 
warmth, moisture, and oxygen. Germination is so dependent 
upon these three external factors that, if either is lacking though 
the other two are properly supplied, there will be very little or no 
germination. Among different seeds, the degree of temperature 
and the amount of moisture and oxygen required for the best 
germination vary. 
Temperature Requirement. — Seeds vary more in the temper- 
ature required for germination than in any other factor. Through 
experience we have learned that among farm and garden seeds 
there are different temperature requirements for germination, 
and that the time of season at which different seeds should be 
planted must be chosen accordingly. Thus Oats, Wheat, and Red 
Clover seeds, which have a low temperature requirement, can be 
planted in the early spring or late fall when the weather and soil are 
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