During the same period, white- winged crossbills (Loxia leucoptera) 

 were observed in the tree-tops plucking seed from open cones. Many 

 other species of birds, including white-throated sparrows (Zonotrichia 

 albicolUs), fox sparrows (Passerella il'iaca iliaca), slate-colored juncos 

 (Junco hyemalis hyemalts), black-capped chickadees (Varus atricapillus 

 atricapillus) , and red-breasted nuthatches (S'ttta canadensis} , were fre- 

 quently sighted in the seed fall area. These birds are seed eaters, and 

 very likely they were taking some seed. 



Many small mammals were seen in the area, including red-backed voles 

 (Clethrionomys gapperi), white-footed mice (Peromyscus lecopus), chip- 

 munks (Tamias striatus}, and red squirrels (Tamias ciurus hudsonicus) . 

 Only the red squirrels were actually observed eating seed, but the other 

 animals listed are known to be voracious consumers of white pine seed. 



No measure of the amount of seed eaten by birds or small mammals 

 was made, but it is likely that a significant portion of the seeds was 

 consumed. 



Conclusions 



Stand density can have a major influence on total seed production. An 

 intermediate density in the mature stand studied here resulted in maxi- 

 mum seed production. 



Total seed yields of well over a million seeds per acre can be expected 

 in good seed years from mature pine stands such as these. 



White pine differs from many other species in that nearly all the seeds 

 are released during a relatively short period in the autumn, and virtually 

 no seed is carried over in the cones to be released during the succeeding 

 growing season. 



The loss of cones caused by insect and animals was relatively un- 

 important in a good seed year, averaging less than 10 percent in 1965. 

 However, it is likely that a similar number of cones would be destroyed 

 in a poor seed year, raising the percentage lost to a much higher level. 



—RAYMOND E. GRABER 



Associate Plant Ecologist 

 Northeastern Forest Experiment Station 

 Forest Service, U.S. Dep. Agriculture 

 Durham, New Hampshire 



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