Willow family (Salicaceae)
narrowleaf cottonwood (Populus angustifolia) -- in March -- Ross, Fort Collins Natural Area, CO green & brown
narrowleaf cottonwood (Populus angustifolia) -- in April -- Arapaho Bend, Fort Collins Natural Area, CO
narrowleaf cottonwood (Populus angustifolia) -- in September -- Red Mountain Open Space, Larimer County, CO
eastern cottonwood (Populus deltoides) -- in May -- Gustav Swanson, Fort Collins Natural Area, CO green & brown
eastern cottonwood (Populus deltoides) -- in April -- Arapaho Bend, Fort Collins Natural Area, Larimer County green & brown
eastern cottonwood (Populus deltoides) -- in February -- River's Edge, Fort Collins Natural Area, Larimer County, Co
eastern cottonwood (Populus deltoides) -- in September -- Boyd Lake State Park, Larimer County, CO
quaking aspen (Populus tremuloides) -- in September -- Williams, Fort Collins Natural Area, Larimer County, CO
quaking aspen (Populus tremuloides) -- in October -- Old Flowers Road, Larimer County, CO green & brown
lanceleaf cottonwood (Populus x acuminata) -- in September -- Well Gulch Nature Trail, Lory State Park, CO green & brown
white willow (Salix alba) -- in April -- Arapaho Bend, Fort Collins Natural Area, Larimer County, CO green & brown
peachleaf willow (Salix amygdaloides) -- in September -- Ross, Fort Collins Natural Area, Larimer County, CO
arctic willow (Salix arctica) -- in July -- Old Fall River Road, Rocky Mountain National Park, CO white & cream
narrowleaf willow (Salix exigua) -- in May -- Pineridge, Fort Collins Natural Area, Larimer County, CO yellow & orange
narrowleaf willow (Salix exigua) -- in May -- Cathy Fromme Prairie. Fort Collins Natural Area, Larimer County, CO yellow & orange
narrowleaf willow (Salix exigua) -- in September -- Williams, Fort Collins Natural Area, Larimer County, CO
grayleaf willow (Salix glauca) -- in September -- Trail Ridge Road, Rocky Mountain National Park, CO white & cream
snow willow (Salix nivalis) -- in August -- Baker Pass, Never Summer Mountains, Routt National Forest, CO red & pink
diamondleaf willow (Salix planifolia) -- in September -- Trail Ridge Road, Rocky Mountain National Park, CO white & cream
Scouler's willow (Salix scouleriana) -- in May -- upper Rist Canyon, Roosevelt National Forest, CO white & cream
crack willow (Salix x fragilis) -- in May -- Gustav Swanson, Fort Collins Natural Area, CO green & brown
weeping willow (Salix x sepulcralis) -- in February -- near Poudre River, Fort Collins, CO green & brown