VITALITY OF PINE SEEDS AND THE DELAYED 

 OPENING OF CONES 



On a visit to California in July, 1908, my curiosity 

 was aroused by the remarkable retention of the still 

 unopened cones in Pinus attcnuata (P. tubcrculata) the 

 knob-cone pine, and to a somewhat less conspicuous degree 

 in the Monterey pine (Pinus rod iota). Trees of Pirns 

 attenuate, may frequently be seen several feet in diam- 

 eter and thirty or forty years old, still retaining unopened 

 all the cones they have produced during their lives, the 

 lowest cones circling the tree within hand's reach from 

 the ground. As all cones are borne on new growth it 

 is obvious that as the branches increase in thickness the 

 peduncles of the cones must be broken loose from their 

 connection with the wood, so as to allow the cones to be 

 pushed out by the annual growth, or the cones will be 

 covered as the tree develops and finally imbedded in 

 the wood. As the cones of P. attenuata are narrow at 

 the base and thus more easily caught by the annual 

 layers, the latter alternative sometimes occurs and the 

 cones are covered by the growth of the tree. 



The cones that remain on the surface of the trunk and 

 branches have no organic connection with the tree, and 

 their peduncles, which are almost an inch long, may be 

 twisted out like a cork from a bottle. It is a well-known 

 fact that in this case the cones never shed their seeds 

 until the tree or branch that bears them dies. 



This remarkable peculiarity is exhibited to almost as 

 great a degree by Pinus radiata (Monterey pine). Of 

 this tree J. G. Lemmon says r 1 



