Field observations suggest that each nutcracker caches 30,000 limber pine seeds in late summer and fall and then recovers about 15,000 of them to get through the winter. Unrecovered seeds germinate and grow. The nutcracker effectively charges the tree one seed for the service of planting one seed.
Ring muhly, Muhlenbergia torreyi, is a clonal species that starts out as a small clump that increases in diameter over the years. That is, a clump of the grass is not a series of individuals, but a single individual.
Contrails from jet engines can coalesce and form man-made clouds. These contrail clouds can affect the weather, but their effect on climate change is uncertain.
The Douglas-fir tussock moth is a native to western North America, and its geographic range is coincident with the range of Douglas-fir; both species are found in British Columbia, all of the western states and the mountains of Northern Mexico. Locally, the preferred host seems to be Douglas-fir, for about a decade ago an infestation killed many Douglas-firs on the north-facing slopes of the canyons west of Boulder.
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