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银杉结实量的年际波动很大，具有明显的大小年之分，一般在２～３个小年之后为１～２个大年。银杉母株的结实量在不同的母树间差别很大，平均单株的球果数仅为６６个。球果结实量在树冠南北侧有差异，南侧球果数占球果总数的６０％；球果结实量的垂直分异明显，树冠中、上部的球果数占总量的９０％以上。松鼠对树上尚未完全成熟的银杉果实的取食危害是长期性的，对银杉种子种群造成严重破坏。以１９９５年为例，被啃食的球果数占球果总数的比重可达１５％左右。试验表明，土壤种子库中地表的银杉种子几乎全部被动物取食，种子埋藏深度增加有利于逃避动物的取食。
The annual growth of fir is very large, with a significant size of the year, usually in 2 to 3 years after the 1 to 2 years. The firmness of the silver fir mother tree varied greatly among the different mother trees, with an average of only 66 cones per plant. Cone density varied in the north and south of the canopy. The number of cones in the south accounted for 60% of the total number of cones. The vertical differentiation of cones was significant. The number of cones in the middle and upper part accounted for more than 90% of the total. Squirrels on the tree has not yet fully ripe silver fir fruit feeding hazards are long-term, on the silver fir seed population caused serious damage. Taking 1995 as an example, the proportion of the number of cones grazed in the total number of cones can reach about 15%. Experiments show that the silver seeds on the surface of the soil seed bank are almost entirely eaten by animals, and the increased seed burial depth is good for avoiding animal feeding.