CONCLUSIONS 



Most ponderosa pine seeds that reach maturity are eaten by animals. Out of 25 

 seeds that reach maturity, 24 provide one of the sources of energy for the small forest 

 animals; the single remaining seed is available for germination. 



Red squirrels, chipmunks, and birds have first chance at harvesting mature seeds 

 in the cone. Ground dwelling mammals, ground feeding birds, and invertebrates must 

 search for the seed remaining on the forest floor. Squirrels have a survival advantage 

 in that they can cache cones from a good cone crop and keep them in storage for 2 years 

 or longer, while the other small mammals and birds must use the current supply of seed 

 before it germinates in the spring. 



Pine and fir seeds constitute an important part of the diet of the small animals 

 inhabiting these forests. How much food in the form of tree seeds does a mature ponder- 

 osa pine--'Douglas-f ir forest produce? On a per-tree basis, mature ponderosa pine trees 

 under natural forest conditions produce about 125 cones per tree and about 60 sound 

 seeds per cone in a moderate seed year--nearly two-thirds of a pound per tree. 



If by chance a fair seed crop year for both pine and fir occurs concurrently in the 

 forests of northwestern Montana, approximately 2 pounds of sound pine seed per acre 

 (24,000 seeds) and about 2 pounds of sound fir seed per acre (84,000 seeds) might mature 

 Of this 4 pounds, squirrels and cone- feeding birds eat or cache about 2.8 pounds, and 

 1.2 pounds are dispersed, of which small mammals and birds consume about 1.1 pounds. 

 Thus, about 0.1 pound (about 600 pine and 2,100 fir seeds) is available for tree regen- 

 eration. A good seed crop of both species concurrently would about triple these amounts 

 However, good seed crops of both species are infrequent (about every 3 to 5 years) and 

 they seldom occur in the same year; thus, the total amount of conifer seed available 

 annually for animals would seldom exceed the total amounts described above for a fair 

 seed crop year. 



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