EFFECT OF REMOVING THE PULP FROM CAMPHOR 

 SEED ON GERMINATION AND THE SUBSE- 

 QUENT GROWTH OF THE SEEDLINGS 



By G. A. Russell 

 Expert, Office of Drug, Poisonous, and Oil Plant Investigations, Bureau of Plant In- 

 dustry, United States Department of Agriculture 



INTRODUCTION 



Heretofore but slight attention has been paid to the germination of 

 camphor seed. The few statements on this subject which occur in the 

 literature refer only to the percentage of seeds germinating under condi- 

 tions existing at the place of experimentation, and all the recorded 

 results indicate a uniformly low germination. Likewise in Florida, pre- 

 vious to the experiments recorded in this article, the germination of 

 camphor seed has been extremely low. 



In commercial plantings in Florida, in which unpulped seeds have been 

 planted with a modified cotton-dropping machine, the average number 

 of seedlings brought to transplanting age on i acre of seed bed has 

 been approximately 20,000. To plant an acre of seed bed requires 3 

 bushels of camphor seed, or approximately 200,000 seeds. The germina- 

 tion on a commercial scale, therefore, has averaged only about 10 per 

 cent, which corresponds closely with the results obtained in various 

 foreign countries. As a consequence of this low germination there has 

 been no considerable extension of large plantings because of the limited 

 number of seedlings available each year. 



EXPERIMENTS IN 1916-17 



In the fall of 19 16 it was decided to make germination tests of camphor 

 seed to determine if possible the cause or causes of the low germination 

 obtained both experimentally and commercially. Accordingly seed was 

 gathered from six individual trees growing in the vicinity of Orlando, Fla. 



Seed from one parent tree. A, was selected from a row grown for shade 

 and ornamental purposes. This tree was 20 years old and a typical 

 representative of the camphor trees in Florida from which seed is gathered 

 for commercial planting. The conditions under w^hich the various lots 

 of seed were collected and the treatment of each before planting are 

 shown in Table I. 



Journal of Agricultural Research, Vol. XVII, No. s 



Washington, T). C. -A-"g- ^S. i9i9 



sjj Key No. G-176 



(223) 



