Cottonwood trees (Populus balsamifera ssp. trichocarpa, P. deltoides and B. fremontii) have a love-hate relationship with people. Some people are allergic to them, had fire damage because of them, or simply have to sweep a lot more. But then they are also thought of as sacred, useful and even a bit edible tree. Not the “cotton” though, so don’t get a head of me. [No… come back here!] They are more than just the mismatched name. These trees are quietly special; very huggable but maybe sticky.
Cottony-seeded cottonwoods are a medicinal as well as edible forage plant
In the “Plant Teachings” book, these trees represent a “wellspring” because they can tap deeper water sources (as a thirsty species) and draw a lot of water to the surface through their own bodies. They thus seem to embody a spirit of their own, which is also associated with wellsprings, like having the spirit of the Earth as the water that lives deep within. They also shade our beloved and very important salmon (and other riparian species) in PNW rivers where they often grow. Cottonwoods would be better named “cotton seeds”, or as I think of them- "snow in summer" trees. They are named for the very flighty seed fluff (which is cluster of a type of very long hair around the seed). You can make some use of the seed fluff, but most foragers will know of cottonwoods for their sticky buds. No mind-altering chemistry in these sticky buds though.
You are most likely to find cottonwoods near fresh water, especially streams and wetlands. They are a tall slim tree, heart-shaped and large leaves with coarsely toothing on edges, gray and fairly smooth bark when young but deeply furrowed as they reach older age. They have alternate branching with chubby buds. This, plus a lack of any remaining fruits will help distinguish them in winter from similar-looking and associated alders or maples.
Alders pretty much always have some of the grape-size cone-fruits among the branch tips & maples of course have that helicopter blade samara seed plus opposite-branching pattern.
Black cottonwood (P. trichocarpa) ranges through the western states, with unique leaves that are more smoothly triangular shaped vs the pinch-pointed S-shaped edge of eastern and Fremont cottonwoods. Black cottonwoods also have a distinctly teardrop shaped bud compared to more evenly tapered eastern cottonwood and plumply round Fremont cottonwood buds. Fremont cottonwood is the tallest, reaching between 40-115’ (12-35m). Cottonwoods grow quickly and are fairly short-lived though often serve as the largest deciduous tree of their habitat, particularly when in the open plains of the central US.
These trees are in the Salicaceae family which includes other wet-footed species of willows, as well as aspens. Cottonwoods (like their kin) have dioecious dangly catkin flowers- with male and female “dingle dangles” on separate trees. So you’ll have a male tree dusting pollen onto everything (sigh), and a female tree later casting fluff EVERYwhere. Even into your home, your car, your shirt! Seriously, talk about dispersal skills. Cottonwood seeds can get around. They drift in as you open the door, even through an open car window. Needless to say, if a fem-cottonwood is in your neighborhood (with a male also nearby), you’ll know. She can produce around 25-40 million seeds each year. Million.
Cottonwood seeds clearly demonstrate the very purpose of the seed ‘cotton’ by blowing all over the place- Dispersal. The seed hairs catch even a slight breeze as they fall from the momma-tree You will see the fluff pooling against curbs, under shrubs, and generally coating the ground where a breeze doesn’t rake them away. The trees can disperse their seeds for several weeks, so there’s a tangible (breathable) cottonwood snow season. And apparently the seeds hairs are flammable. So be careful. I haven’t tried lighting them myself, but after reading a warning from a fire department… I totally want to run an experiment. Safely. But the fire fighters are to be believed all the same- highly flammable (they do have a lot of oxygen space between their dry hairs probably made of cellulose). The seed hairs that make up this distinct cotton are in fact similar to the actual cotton plant’s (Gossypium spp.) seed hairs, just a bit less. Of course these are very different plants, as cotton is in the mallow family (Malvaceae) and has more familiar cup-shaped flowers evocative of a hibiscus. That seed dispersal similarity is what we call convergent evolution, two very unrelated species having very similar traits. All cottonwood fruits look like a narrow cluster of green gently pointed grapes before the fluff starts to poof out to spread the seeds within.
Cottonwoods vs poplar
(black cottonwood vs black poplar- Populus balsamifera ssp. trichocarpa vs Populus nigra)
Funny fact: black cottonwood isn’t Populus nigra (nigra meaning “black” in Latin of course). Though because common names are a total crap-shoot, sometimes P. nigra is called black cottonwood. That tree is native to Europe and is most often called black poplar to be very on-the-nose. The leaves of black poplar may be slightly longer with elongated points than cottonwoods though otherwise very similar. They also produce the cottony seeds so really are another cottonwood, right? Black cottonseed, of Europe. That’s how I will think of black poplar. It is found all over the US as an introduced species and valued for it’s more columnar growth form (like a fluffy stick with short branches all along the tall trunk vs the broad upper canopy of other cottonwoods). You will know these if you’ve camped in dry and open Eastern Washington campgrounds with trees encircling the area (also found as a border in other properties) because they’re bushiness makes them good windbreaks. But the snow-season of their seed dispersal makes for interesting camping during that time.
Cottony-seeded cottonwoods are a medicinal as well as edible forage plant, with amazingly sticky sappy swollen buds in mid-late winter that can make what is called the Balm of Gilead (falsely named after similar balm mentioned in the Judeo-Christian bible, made from very different tree, possibly in cashew family). This balm or salve is very soothing, antiseptic, healing and even pain-relieving. That may be the best-known foraging use of cottonwoods but the leaves and inner-bark are also edible, as is the sap but not exactly tappable as maple (or birch). The inner bark of young sprouts is tasty, slightly sweet and nutritious. Its sap is similarly sweet and starchy and can be eaten raw or cooked. Leaves are less bitter and thus more preferred than the medicinal inner bark which makes a very effective soothing tea. While also edible as a fresh green, cottonwood leaves are still pretty bitter so cooking mixed with other vegetables or greens may be helpful. The young flower catkins are also edible, and can be fried up lightly in plain butter to taste their delicate flavor, or battered and fried like tempura. Harvest them when young but have loosened into a close cluster (past the tight-purple caterpillar-looking phase) but have not opened any flowers yet.
The waxy sticky buds in early spring can make an amber yellow dye. From what I can tell, each species is pretty similar and the uses can be applied to all. Certainly they have difference in potency/taste. I’d love to do a cross-country comparison! Foraging road trips!
What English-speakers today call cottonwood, was previously named “waga chaN” by the Dakotas, “maa zhoN” by the Omaha-Ponca tribes, and “natakaaru by the Pawnee, all in North America and it has been a special tree to many First Nations peoples. The Spanish also named them "alamo", yes the same Alamo's namesake (it's on the San Antonio river). It was a sacred tree of life for the Comanche. The Hidatsa of the Siouan people in North Dakota saw that the tallest tree of the Upper Missouri valley, the grand cottonwood, had the strongest "shade" or soul of the local plant life. It was thought to possess a helpful intelligence and thus given special respect among their people. The Hidatsa are said to once never fell cottonwood trees but would only use naturally fallen logs, often those along river banks after spring floods knock them loose along with parts of the river bank.
“It is said that the spirit of the tree cries, while the roots still cling to the land and until the trunk falls with a splash into the stream.”
-The Golden Bough, ‘The worship of trees’, by Sir James Frazer.
First Nations people were not the only to see wrong in harming grand trees, finding human features in these woody beings. “For why should the slaughter of an ox or a sheep be a greater wrong than the felling of a fir or an oak, seeing that a soul is implanted in these trees also?” – Porphyry the vegetarian philosopher of ancient Greece.
Cottonwoods very conveniently drop some smaller branches throughout the winter. The tree can hold so much water at this time, that even large branches often become too heavy to hold, especially in windstorms. They also drop branches purposefully in a process called cladoptosis, as a natural self-pruning. This is especially documented in black cottonwoods (Cottonwood: Establishment, Survival and Stand Characteristics). So feel free to dig in to those dropped branches for bud harvesting as they were rejected by the tree as not needed. Waste-not, I say. These being rejected doesn’t mean there’s anything wrong with the buds.
For medicinal uses, cottonwood buds are particularly valuable because they are heavily coated in protective sap which can be extracted to make a medicinal balm. Buds can be used from any cottonwood species but the “balm cottonwoods” (P. balsamifera) and balm-of-Gilead poplar (P. x jackii) are the best. Populus x jackii is actually a hybrid of the black and Eastern cottonwood. Pick buds that are large and swollen and especially sticky for best potency. They often glisten and will break off from the branch easily. Beware- very sticky and can stain your hands and even clothes. Plan Ahead- bring disposable gloves and a hanky or jar or something to contain them that can get sticky.
In wintertime the aromatic sap is filling the buds. The sap contains a variety of medicinal components, including compounds that kill germs, ease pain, and promote skin regeneration. Most parts of the tree in fact contain salicin and populin, which accounts for many medicinal applications including fever and inflammation reduction, and pain relief. If in a bind, the medicinal sap it can be used right off a bud for a sticky pain-relief, etc.
The difficulty in harvesting buds is that they are extremely sticky (think pine sap), not joke. While harvesting I had trouble getting them to let go of my fingers. I was reminded of the scene in Christmas Vacation where Clark Griswold tries to read a magazine with pine sap all over his hands. But it’s worth a slight annoyance. Likely you will find several small branches dropped on the ground to harvest from and feel free to take all you want. But if you find some low enough branches still on the tree, only take a few of the non-terminal buds (don’t take the terminal/tip-most bud which will be the main continuation of that branch for next year). One of the best ways to extract the medicinal qualities of the sap is to infuse the buds in an oil. The oil can then be used as it is (as a salve) or turned into a balm by mixing with wax. Cottonwood salve has been used for centuries to treat a variety of skin troubles, from cuts and scrapes to minor burns and bruises. After harvesting, you may want to dry the buds overnight before extraction.