No. 515] 



VITALITY OF PINE SEEDS 



079 



This admirable little tree grows on brushy, sun-beaten slopes, which 

 from their position and the inflammable character of the vegetation are 

 most frequently fire-swept. These grounds it is able to hold against 

 all coiners, however big and strong, by saving its seeds until death, 

 when all it has produced are scattered over the bare cleared ground, 

 and a new generation quickly springs out of the ashes. 



This statement of Mr. Muir's implies that all or a 

 large part of the seeds produced during the life of the 

 tree are capable of germination when shed, and this 

 seems to be the opinion of others (see Lemmon, as quoted 

 above, under P. muricata). 5 



Now it is a well-known fact that pine seeds as a rule 

 are very perishable (seeds of P^palustris will not germi- 

 nate, according to my experience, the second spring after 

 their maturity) and it is important to test by actual ex- 

 periment to what extent seeds retain their vitality under 

 such conditions. In looking over the literature I can 

 find but one experiment that has been made to enlighten 

 us on this point. 



In 1874 Dr. Engleman collected a branch of Pinus 

 contorta from Colorado (the plant being probably var. 

 Murray ana, or lodge pole pine) and after keeping it four 

 and a half years, he sent it to Professor C. S. Sargent, 

 of the Harvard Arboretum, to test the seeds. Professor 

 Sargent planted the seeds in 1879, and his results, as re- 

 ported in Bot. Gazette, Vol. 5, p. 54, 1880, were as follows : 



Merriam's "Results of a Biological ^Survey of Mount Shasta, California" 

 (North American Fauna, 16, 1899) would indicate that its seeds have a 

 hard time on Mount Shasta. He says: 



the branches, and down the trunks to 10 or 12 feet from the ground. Some 

 of the cones must have been 20 or 30 years old. and perhaps much older. 

 I cut off a lot of the old lower cones to see if the seeds were good, and put 



of them were full of worm dust, with only now and then an undiscovered 

 seed or a fat white worm. Cones of medium age (5 or 6 years back from 

 the end of the branch) were invariably occupied by worms and worm dust, 

 and usually contained few good seeds. Cones only 1 or 2 years old were 

 rarely wormy. A great many of the old cones had been dug into by wood- 

 peckers, either for seeds or, more likely, for the fat white grubs that live on 



