It’s snowing again at Putah Creek! It’s as close to snow as we’re going to get, anyway, thanks to Fremont cottonwood (Populus fremontii). This tree is a magnificent component of the river forest ecosystem. Named for the silky, cottony hairs that allow its seeds to float on the wind, Fremont cottonwood dominates the forest canopy at heights of up to 100 feet. It is identifiable by its heart-shaped leaves, and is considered a keystone species in river corridors of the Central Valley, providing structure to the riparian forest, and habitat, shade, and food to abundant birds, mammals, and insects.
Fremont cottonwood is well-adapted to flooding and disturbance in its home along waterways. Seeds readily establish in the waterlogged soils as floodwaters recede, and a branch broken off during a flood can send out roots and grow a new tree downstream. We take advantage of this useful characteristic in habitat restoration by plunging branches, or “poles,” from mature cottonwoods into riverbanks to easily grow new trees. This winter’s record rains and flooding may lead to a bumper crop of cottonwoods along Putah Creek – we’ll be keeping a lookout for them.
And they are seeding right now! Go out this month and enjoy the “snow” along Putah Creek.