Salicaceae

Willow Family

Aspen, Cottonwood, and Poplar

FAMILY: Willow family (Salicaceae) – Populus genus.

SPECIES: All species of the Populus genus are edible. #1 white poplar (Populus alba L.). #2 narrowleaf cottonwood (Populus angustifolia E. James). #3 balsam poplar (Populus balsamifera L.). #4 eastern cottonwood (Populus deltoides W. Bartram ex Marshall). #5 Fremont’s cottonwood (Populus fremontii S. Watson). #6 quaking aspen (Populus tremuloides Michx.). #7 black cottonwood (Populus trichocarpa Torr. & A. Gray ex Hook.).

TO UTILIZE AS FOOD: The inner bark, sap, and young shoots of all species are edible (Couplan  p. 154). In addition, the flowers of all species are edible (Tilford p. 114). The following assessment is based on various parts of narrowleaf cottonwood (P. angustifolia), eastern cottonwood (P. deltoides), Fremont’s cottonwood (P. fremontii), black cottonwood (P. trichocarpa), and aspen (P. tremuloides). 

Inner bark: Cottonwood trees have thin, smooth, white outer bark. As they age, lower trunks often develop thick, brown, deeply furrowed outer bark. Cottonwood trees produce extremely bitter chemicals to discourage animals from gnawing the trunks. These chemicals are concentrated in areas where animals can reach and less concentrated further up the trees. Despite this adaptation, upper bark does not taste any better than lower bark to the human palate. Cooking has no effect on the flavor. Inner bark is fairly easy to process into flour. Of course, calling it flour may be too kind! It needs to be dried prior to grinding. Cottonwood flour is nearly pure fiber. Food value is minimal, so harvesting these trees is barely worth the effort.

Winter buds and shoots: A new life cycle begins when winter buds swell, elongate, and become young branch tips. Elevation influences when this life cycle begins. Winter buds are protected by tough scales that come in a variety of dull colors including: green, red, and brown. Interior portions are light green, full of life, and tender like garden vegetables. Hairs are often present on the protective scales. Hairs pose no problems and scales can be removed. The real problem is flavor, not texture. Cottonwood buds are permeated with sticky, aromatic, terribly acrid resins. Raw buds can burn your throat, and cooked buds aren’t much better. These resins greatly diminish the potential for cottonwood buds to serve as food. As the winter buds elongate into new shoots, the acrid intensity declines, but it never seems to decline enough. Cottonwood shoots are too acrid, bitter, and foul to honestly be considered food.

Flowers: Cottonwood trees produce male (staminate) and female (pistillate) flowers on separate trees. Flowers occur in clusters called catkins or aments. Whole catkins of both genders are soft, tender, and easy to harvest in quantity from lower branches. The flavor ranges from awful to palatable, usually being closer to palatable. Flowers rank among the best tasting parts of cottonwoods. Male flowers taste slightly better than female flowers. Both can serve as fresh vegetables, assuming they’re not overrun by acrid, bitter, or resinous compounds. Male flowers have accents suggesting corn and green beans. Female flowers taste bland. Cooking improves the flavor and reduces any allergenic potential from the pollen. Male flowers have a more delicate texture than female flowers. Shortly after blooming, female flowers develop into fruits.

Young fruits: Cottonwood trees produce capsules that initially resemble clusters of green cherries. Young capsules are edible in this green stage until seeds begin to develop. Once seeds develop, the capsules acquire the texture of “green berries stuffed with carpet.” Gathering should be done before this point. In the green stage, the capsules range in flavor from mediocre to acrid, bitter, resinous, and unappealing. No foods on the commercial market provide a suitable comparison. The texture is chewy and tacky. Marinating the capsules in vinegar improves the flavor and effectively preserves this traditional food. Sautéing them in butter also helps. Boiling produces cloudy green wastewater with a layer of oil on the surface. Cottonwood capsules make an interesting garnish. Eventually, the capsules dry out and release a storm of fluffy seeds.

Aspen (P. tremuloides) trees are thoroughly distasteful. None of the parts stray into the territory of palatable. At best, aspens are resources of desperate times barely suitable for consumption. Inner bark flour is exceptionally unappealing. Winter buds are protected by tough scales and have scanty edible portions. Male and female flowers occur on separate trees. Male flowers have hairy bracts that impart a “carpet-like” texture. Even the youngest male flowers emerging from winter buds are cursed with annoying hairs and lack any vegetable-like qualities. When eaten raw, they taste unappealing, yet better than other parts of aspens. Except for the hairs, the texture is mostly chewable. Cooking offers an improvement. Simmering yields a murky wastewater that might pass a taste test with a score just above failing. Female flowers remain distant from anything that could honestly be described as food. Young fruits also taste unappealing. Aspen capsules are tiny and subtended by hairy bracts. Overall, aspen trees appear to be a dire resource.

IDENTIFICATION: The Populus genus is represented by about 20 species in the United States, of which 7 occur in the Southwest. They differ from willows by having winter buds covered with several scales and individual flowers subtended by a conspicuous cup-shaped disk. Other, less reliable differences include: drooping flower clusters, deeply fringed bracts, and numerous stamens.

Description of cottonwoods (the Populus genus): FORM thornless, deciduous, medium to large trees about 15-40 meters tall; BARK generally white in youth, becoming grayish-brown and furrowed in age; BUDS covered by several (3 or more) scales, often resinous, and sometimes hairy or aromatic; LEAVES simple; alternate; stalked; the stalks round, flat, grooved, or u-shaped in cross section, and sometimes with tiny glands near the junctions with the leaf blades; blades lanceolate to widely heart-shaped to rounded; margins usually toothed; surfaces usually hairless; FLOWERS unisexual; male and female flowers on separate trees and arranged in drooping clusters (catkins) appearing before or with the leaves; each flower subtended by a cup-shaped disk; bracts usually deeply fringed; sepals 0; petals 0; pistils 1, the ovary superior; stigmas 2-4; stamens numerous; FRUITS capsules 2-4-valved; seeds bearing long silky hairs for dispersal by wind; HABITAT throughout the United States, including the northern Sonoran Desert (also called the Colorado Desert), several species preferring riparian areas; blooming January to July.

REFERENCES: Couplan (p. 154) indicates that all species of the Populus genus have edible inner bark, sap, and young shoots. Likewise, Tilford (p. 114) indicates that all species have edible catkins (flower clusters). #1 white poplar (Populus alba): inner bark Sturtevant (1919 p. 450). #2 narrowleaf cottonwood (Populus angustifolia): inner bark and flowers Moerman (p. 191). #3 balsam poplar (Populus balsamifera): inner bark and sap Moerman (p. 191). #4 eastern cottonwood (Populus deltoides): inner bark, sap, and flowers Moerman (p. 191). #5 Fremont’s cottonwood (Populus fremontii): inner bark Kirk (pp. 261-263); flowers Moerman (p. 192). #6 quaking aspen (Populus tremuloides): inner bark and sap Moerman (p. 192). #7 black cottonwood (Populus trichocarpa): inner bark and sap Moerman (p. 191) and others.

Willows

FAMILY: Willow family (Salicaceae) – Salix genus.

SPECIES: All species of the Salix genus are edible. Goodding’s willow (Salix gooddingii C. R. Ball) was the predominant southwestern species utilized as food. Botanically, it’s very similar to black willow (Salix nigra) of the eastern United States.

TO UTILIZE AS FOOD: All willows have edible inner bark (Couplan p. 155). In addition, the flowers of Goodding’s willow (Salix gooddingii) are edible. Willow shoots and leaves are generally too bitter for consumption. Various parts—inner bark, leaves, flowers, or young fruits—of eleven species were sampled for this reference. The following article is a consensus of those species. 

Willow inner bark is a rather dire resource due to its bitter flavor. Finding large trees to harvest is imperative. Small trees and shrubs have thin inner bark layers that aren’t worth the effort of harvesting. Southwestern species tend to be shrubs. Willow inner bark is very similar to that of cottonwoods. Harvesting and processing techniques are likewise similar. After removing the outer bark, the inner bark needs to be dried, and then ground into flour. Boiling the inner bark prior to drying it improves the flavor, but at the expense of losing nutritional value. Willows are dominant shrubs and trees along watercourses, but their value as food seems minimal.

Willow flowers are rarely reported to be edible. They appear in clusters called aments or catkins. In most species, male and female flowers are located on different trees (dioecious). Flowers can appear before, with, or after the leaves. Willow flowers bloom early, except at higher elevations, where they can bloom well into summer. Some species produce hairy flowers that collectively look like cotton balls. Others are hairless. Hairless species are preferable, but some of the hairy ones are fine. Assuming willow flowers are safe, they can be eaten fresh or cooked. Fresh flowers taste a little better, but they tend to be allergenic. Boiling neutralized the allergenic potential of the species sampled, so willow flowers seem best as cooked vegetables. Bitter and resinous overtones are normal, but they’re seldom overwhelming. Grocery store foods lack a suitable comparison. Male flowers tend to taste better than female flowers, but they also support a thriving metropolis of bugs and possess greater allergenic potential. Female flowers are normally less infested and soon develop into fruits. Young fruits taste less appealing than the flowers, but they should qualify as palatable. Developing seeds soon impart a chewy texture, so only the youngest fruits are worth gathering. Of all the various parts of willows, the flowers seem to be the best part for consumption and the leaves seem to be the worst. Most references are for the inner bark. Keep in mind that only Goodding’s willow (S. gooddingii) and a few other species are reported to have edible flowers.

NOTES: Willow branches were a popular choice for making baskets, bows, traps, and numerous other crafts. Tea brewed from the inner bark of various willows was used medicinally to relieve pain, inflammation, coughs, and fevers.

IDENTIFICATION: Approximately 110 species of the Salix genus are found in the United States, of which about 30 grow in the Southwest. Willows are easy to recognize as a group, but exact species are challenging to identify. Willows differ from cottonwoods by having winter buds with one scale and flowers lacking cup-shaped disks. Other differences include: upright flower clusters, entire bracts, and 2 stamens. Not all willows conform to these differences. Willows are abundant in the Southwest. Almost no watercourse is without a supply.

Description of willows (the Salix genus): FORM shrubs or trees; BUDS each covered by one smooth, nonresinous, cap-like scale; LEAVES simple; alternate; blades lanceolate to elliptic, commonly longer than wide; margins smooth or toothed; surfaces often hairy; FLOWERS unisexual; male and female flowers on different plants and arranged in upright-spreading clusters (catkins) appearing before (precocious), with (coetaneous), or after (serotinous) the leaves; bracts entire or toothed; sepals 0; petals 0; pistils 1, the ovary superior; stamens 2 (sometimes 1-8); FRUITS capsules 2-valved; seeds numerous, finely hairy, and cottony; HABITAT throughout the United States; blooming January to July.

REFERENCES: Couplan (p. 155) indicates that the inner bark of all species in the Salix genus is edible. Goodding’s willow (Salix gooddingii): inner bark Moerman (p. 236); flowers Moerman (p. 236).