Wild buckwheat on the Colorado Plateau

Wild buckwheat is not the grain in your pantry. The genus Eriogonum is a group of several hundred species of the buckwheat family, nearly all of them native to western North America, and most of them shrubs or matted perennials of dry ground. The grain called buckwheat, Fagopyrum esculentum, is an unrelated crop from Asia, and the two share a family name and little else. On the Colorado Plateau, Eriogonum grows on the same sandstones, shale slopes and sagebrush flats that hold most of the region's archaeological sites, which is why the plant turns up in ethnographic plant lists and, less often, in the excavated record.

What is a wild buckwheat, and how does it differ from the buckwheat grain we eat?

The difference is taxonomic before it is culinary. Fagopyrum esculentum belongs to the Polygonaceae as well, but to a different tribe, and it was domesticated in southwest China and spread to Europe and North America as a crop. Eriogonum was never domesticated. Its seeds are small, its yields are low, and no historic people of the plateau relied on it as a staple.

That does not mean it went unused. Ethnographic accounts from Puebloan and other groups record Eriogonum roots and leaves in medicinal preparations, and the seeds of some species were parched and eaten in small quantities or ground into a thin mush during lean periods. The plant's greater importance was probably indirect: wild buckwheats bloom late, from July into October, when many other flowers on the plateau have finished. That late nectar and pollen feeds the bees, wasps, butterflies and hummingbirds that in turn occupy the same ground the fields and villages occupy. A reader who wants the genus treated on its own terms, species by species, will find it at the wild buckwheat journal, which keeps to the plants and the dry gardens built around them.

How do you identify a wild buckwheat on a hike?

Start with the flower head, because it is unlike anything else on the plateau. What looks like a single bloom is a cluster of tiny flowers, and each cluster sits inside a small cup of fused bracts called an involucre. The involucre is the genus's most reliable mark. It may be smooth, hairy, or covered in woolly white hairs, and its shape, bell, cup, or turret, is often what separates one species from the next. The flowers themselves are usually less than a quarter inch across, white, cream, yellow, pink or red, and they sit above the involucre on short stalks.

Leaves come second. Most Eriogonum leaves are basal, meaning they rise from the base of the plant rather than along the flowering stems, and many are woolly or gray-green on at least one surface. The wool is a real field character, not a trick of the light: it reflects heat and slows water loss, which is why so many species of the Four Corners states carry it. A hand lens helps, but on a bright afternoon the wool is visible to the naked eye against dark shale.

Habit comes third. Some species are low mats a few inches high, some are rounded subshrubs a foot or two across, and a few, such as the sulfur buckwheat of the Great Basin and the higher plateau margins, form loose mounds of pale yellow flowers that are visible from a distance. Habitat narrows the list further. Sandstone ledges, clay badlands, volcanic soils and gypsum outcrops each carry their own set, and a species that grows on one is usually absent from the others.

What does the archaeological and ethnographic record actually show?

The record is thinner than the plant's abundance would suggest, and it is worth saying so plainly. Eriogonum does not appear in the plateau's archaeological literature as a major food plant. It appears in ethnographic plant lists, in pollen and macrobotanical samples from some sites, and in the ethnographic present, where its medicinal and minor food uses were recorded in the twentieth century.

Pollen from Eriogonum is distinctive enough to be identified in sediment cores and packrat middens, and its presence in a midden or a core is usually read as evidence of local dry ground rather than of human use. That is a useful distinction. A pollen grain in a sample tells you the plant grew nearby; it does not tell you anyone carried it there. Macrobotanical remains, charred seeds or root fragments from a hearth, are stronger evidence, and they are uncommon for this genus.

The ethnographic literature is more generous. Recorded uses include poultices and infusions from roots and leaves, and seeds gathered in small amounts. None of these accounts describe Eriogonum as a crop, a stored food, or a plant tended in fields. It was a plant of the edges, gathered when it was available and used when it was needed.

Which buckwheat should a small dry garden start with?

For a garden in the dry Southwest, the safest first plant is usually one of the low, long-blooming subshrubs rather than a rare endemic. Sulfur buckwheat, Eriogonum umbellatum, is the common recommendation: it is widely available, it tolerates cold and drought, and its yellow flower heads hold from early summer into fall. California buckwheat, Eriogonum fasciculatum, is a larger shrub for lower and warmer ground, and it is one of the best late-season nectar plants in the region. Saint Catherine's lace, Eriogonum giganteum, is a Channel Islands plant and wants milder conditions than most of the plateau can offer.

Three practical points apply to all of them. Plant in fall, not spring, so roots establish before heat. Give the plant sharp drainage, sand or gravel mixed into the native soil, and water it through its first summer only. Prune lightly after bloom, removing spent flower heads and no more than a third of the stems, to keep the plant compact rather than leggy. Seed is also workable: Eriogonum seed germinates best with cold moist stratification, and a winter sowing outdoors suits the genus better than a warm windowsill.

Where to look on the plateau

Wild buckwheat is easiest to see in late summer, along roadsides and trails that cross shale or sandy ground, and in the openings between pinyon and juniper. It is often growing within sight of a recorded site, on the same slope, in the same thin soil. That coincidence is the reason the plant belongs in a notebook about the plateau's archaeology at all: it is part of the ground the sites sit on, and reading it is part of reading that ground.

Source: fs.usda.gov.