THE RELATION OF GERMINATION IN THE GREENHOUSE 



AND NURSERY 



By S. B. Show 

 Forest Examiner, Feather River Bxperiment Station 



After all questions of nursery practice are settled, after the correct 

 source of seed is determined, after the desired output of the nursery is 

 set, the best-laid plans will gae aglee if the amount of seed sown is im- 

 properly gauged. It is therefore essential that each lot of seed should 

 be properly tested; that the test results should be co-ordinated with 

 actual germination in the nursery, and finally that the nurseryman 

 should follow the indicated figures rather than his own individual 

 hunch. 



Seed-testing in the greenhouse is done under fairly well-controlled 

 conditions, which vary only slighth- from year to year. These condi- 

 tions are, however, artificially created and do not correspond to condi- 

 tions in the nursery, which cannot be controlled and which vary from 

 year to year decidedly. It follows, therefore, that results of green- 

 house tests cannot be applied directly to field sowing, and that certain 

 corrections must be made before they are usable. 



The factors influencing both rapidity and total amount of germina- 

 tion of a given lot of seed are : 



1. Temperature of soil. 



2. Character of soil. 



3. Amount of light. 



4. Amount of water. 



5. Depth of cover. 



Various investigators have shown that, with other factors constant, 

 each of these influences has a very marked eft'ect on the germination 

 of a given lot of seed. The last three factors can be pretty well stand- 

 ardized, both in the greenhouse and nursery. The character of soil is 

 predetermined, except as changed by fertilizing; temperature is conse- 

 quently the variable. 



TlIK SOIL IWCTOR 



In so far as this district is concerned, four distinct soils are to be 

 considered, as follows : 



