

What Do We Plant? 



FIRST THE SEED, THEN THE TREE 



PAUL O. RUDOLF 



IN THE United States more than 

 600 species of woody plants are use- 

 ful for conservation planting, and some 

 75 million acres are in need of refores- 

 tation. For that, more than 100,000 

 tons of forest seeds will be needed. We 

 should therefore know all we can about 

 forest seeds where they are borne, 

 how often good crops come, when seeds 

 are ripe, when is the best time to col- 

 lect, how to clean them, how to store 

 them, how to obtain prompt germina- 

 tion, how good they are, and what their 

 origins are. 



SEEDS DEVELOP from flowers. The 

 floral organs are the stamens and the 

 pistils, which produce the sperm, or 

 male cells, and the egg, or female cells, 

 which, when united, produce the seed. 

 Some trees and shrubs have bisexual, 



Above: A onetime Navy plane is used to seed 

 white pine on burned-over forest lands in 

 Maine. 



or perfect flowers. Many, however, 

 have stamens and pistils borne in sepa- 

 rate flowers, either on the same plant 

 or on separate plants. Others have both 

 perfect and unisexual flowers on the 

 same plant. A knowledge of these 

 habits helps the seed collector to know 

 what trees are likely to produce seeds 

 and also what crop to expect from the 

 abundance of blossoms. 



A typical tree seed consists of an 

 embryo, usually embedded within an 

 endosperm (sometimes very thin or 

 even absent) , all enclosed in one or two 

 seed coats. The embryo is a complete 

 plant in miniature. The endosperm 

 contains food reserves that become 

 available for germination and early 

 growth. The seed coat protects the em- 

 bryo from injury before germination. 



Tree seeds range in size from the 

 powderlike rhododendron seeds to the 

 large black walnuts. They differ greatly 

 also in shape, color, and other char- 

 acteristics. From the standpoint of col- 



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