EFFECTS ON GERMINATION 



37 



the death of the plant. The farmer says his crop has been 

 burned since it has that appearance. As a matter of fact 

 water may have been drawn put of the plant through the 

 roots. This, taken with the loss by transpiration, des- 

 sicates the plant to the point at which it dies. 



Effects on Germination. Before a seed can germinate 

 it must absorb water. Ordinarily when a seed is planted 

 in a moist soil it absorbs moisture and swells. At once 



Fig. 4. An Orchard Planted on Land that Came from a Formation 

 High in Soluble Salts. The Salts had Killed Most of the Trees 

 by the Second Year. 



the enzymes contained in the seed convert part of the 

 starch into sugar which increases the strength of the solu- 

 tion in the seed. This in turn hastens absorption and the 

 seed soon contains sufficient moisture with which to carry 

 on rapid cell division and growth. Within a few days a 

 root is sent out, then a shoot for the top, and a new plant 

 is growing. 



When a seed is placed in a strong salt solution or a soil 

 that has a large amount of alkali, it does not absorb mois- 

 ture; consequently, it lies dormant the same as it would in 

 dry soil or in dry air. The coating on the seed protects it 

 from absorbing most of the salts. It may not be injured, 

 and as pointed out by Slosson (13) it will germinate when 

 removed from the alkali soil to conditions favoring ger- 



