CHAPTER XV 

 THE FOREST NURSERY (Continued) 



1. The Overcoming of Stock Losses from Preventable 



Causes 



SUCCESSFUL nursery practice demands fully stocked seedbeds 

 and transplant beds. Some losses in the seedbeds after germina- 

 tion should be expected due to the elimination of weak individuals. 

 When fresh seed of high quality is sown it should not exceed 5 to 

 10 per cent. Losses in the transplant bed should be expected also. 

 These minor losses due to various causes are of little moment and 

 should be provided for in the seeding. Excessive losses due to 

 preventable causes require special consideration. Such losses are 

 liable to occur in any nursery where provision is not made for 

 eliminating the cause or for checking the damage as the loss begins. 

 They relate to : 



a. The loss of viable seed between the time of sowing and com- 

 plete germination. 



b. The loss of plants in the seedbeds and transplant beds. 



2. THE Loss OF GERMINABLE SEED 



Aside from the sowing of adequate seed of high quality under 

 conditions which afford the best environment for germination, 

 the fullness and evenness of the stand at the start depend chiefly 

 upon the percentage of loss in viable seed after sowing and 

 before germination takes place. This loss is due almost entirely 

 to seed-eating rodents. Squirrels, chipmunks, gophers, and vari- 

 ous species of mice are usually very destructive when abundant 

 in the vicinity of the nursery unless efficient protective measures 

 are in effect. The damage by rodents is almost entirely confined 

 to the period preceding germination, during which time the seeds 

 are dug up and destroyed, although large seeds such as chestnut 

 and oak are often destroyed by squirrels several weeks after 

 germination starts. Squirrels and chipmunks work in the day- 



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