Naked-stemmed Buckwheat

Naked-stemmed Buckwheat © GBarton

Naked Buckwheat, Nude Buckwheat, Ear-shaped Wild Buckwheat
Eriogonum nudum var. auriculatum
NATIVE – CA ENDEMIC

Description (Jepson, PlantID.net)

    • Eudicotyledon
      • Eudicots are a major lineage of flowering plants; see family for general characteristics
    • Buckwheat Family (Polygonaceae)
    • Perennial, drought tolerant herb
    • Leaves
      • Mostly basal, with wavy margins
      • Smooth dark-green upper surface; underside with short woolly hairs (tomentose)
      • Leaf base surrounds the stem (sheathing)
    • Flowers
      • Inflorescence (flower arrangement) of long, leafless, branching stems with rounded flower clusters at nodes and tips
      • Each cluster of individual flowers held in 1-5 bunches of vase-like bracts (modified leaves), called involucres, attached directly to the stem
      • White to pink
      • Ovary superior (attached above other flower parts)
    • Fruit is an achene (a single-seeded, dry fruit that does not split open)
    • Height to 20 in.

    Distribution

      • Native and endemic (limited to) California
        • Grows in sandy, clay, or gravel soils on exposed, sunny sites in mixed grasslands, chaparral, and oak and conifer woodlands
        • See Calflora for statewide observations for this plant
      • Grows at elevations to 4,000 ft.
      Flower at Node © AFengler

      Uses (Picking or removing any natural material from public land is illegal)

        • Supports a large and varied community of insects, including nectar- and pollen-eating bees and predatory insects, like wasps
        • Native buckwheats (Eriogonum species), in general, are valuable food sources for the larval stage of several butterflies and moths
          • Larval food for butterflies such as Acmon blue (Plebejus acmon), Gorgon copper (Lycaena gorgon), and bramble hairstreak (Callophrys perplexa)
          • Caterpillars of some butterfly species are monophagous and will feed on only one genus or one species of plant
            • Lange’s metalmark (Apodemia mormo langei) larvae, for example, only feed on Eriogonum nudum ssp. auriculatum
            • Exclusive association to a plant can increase possibility of coextinction (Everipedia 2020)
        • Birds and small mammals eat the seeds
        • Native people ate the leaves and used hollow stems as drinking tubes or for smoking pipes

        Name Derivation

          • Eriogonum (er-ee-OG-an-um) – from the Greek poly, “many,” and gónato, “knee,” referring to the swollen stem nodes (joints) characteristic of this family
          • nudum (NOO-dum) – Latin for “bare” or “naked”
          • auriculatum (aw-rik-yoo-LAY-tum) – from the Latin auris, “ear,” meaning “having ear-like structures”
          • Buckwheat – from Old English for “beech-wheat”
            • 3-sided seeds resemble beechnuts
            • Though not related to wheats, which are in the Grass family, the seeds of some buckwheats are ground into meal or flour

          Notes

            • Although in the same family, the cultivated buckwheat (Fagopyrum esculentum), which is native to Asia, is not closely related to Edgewood’s native buckwheats; see Buckwheat family to learn more about this pseudograin
            • In 2016, a large population of Mount Diablo buckwheat (Eriogonum truncatum) was discovered at Black Diamond Mines Regional Preserve in Antioch (Save Mount Diablo 2016)
              • The species was thought extinct for almost 70 years until rediscovered in 2005 in a single, tiny population on Mount Diablo
              • This rare buckwheat is on protected land, but many plant species that have evolved to fill specific ecological niches (contributing to the extraordinary diversity of California’s plants and animals) grow in undeveloped lands that are subject to intense development pressures
            • Edgewood’s naked-stemmed buckwheat is classified as a variety
              • Subspecies rank is used to recognize geographic distinctiveness, whereas variety rank is appropriate for variants seen throughout the geographic range of the species; in practice, these two ranks are not distinct
            Flower Involucres (L), Top of Leaves (M), Bottom of Leaf (R)
            © DSchiel

            ID Tips

              • Edgewood has 3 species of buckwheat, each quite distinct
                • Wicker buckwheat (E. luteolum var. luteolum) is a small, delicate-looking annual, with wiry stems and tiny clusters of white to rose flowers with darker stripes
                • California buckwheat (E. fasciculatum), an evergreen shrub, exists on the slopes of the Central Ridge and is believed to be introduced as the species is outside its natural range

              At Edgewood

                • Found in serpentine grasslands
                  • See iNaturalist for observations of this plant
                    • Note observations are for Eriogonum nudum
                • Flowers June – September

                See General References

                Specific References

                  Everipedia International. 2020. Eriogonum.

                    Hammerstrom, K. 2016, Nov. 16. California Native Plant Profile: Buckwheat – UC Master Gardeners of Monterey Bay – ANR Blogs

                      Hemingway, M. 2012. Plant Guide: Naked Buckwheat. U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), National Plant Data Center.

                        Save Mount Diablo. 2016, Oct. 1. Mount Diablo Buckwheat Critically Endangered Wildflower Discovered Near Antioch.

                          Shapiro, A.M. and Manolis, T.D. 2007. Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions. University of California Press, Berkeley-Los Angeles, California.