Limnanthes floccosa ssp. grandiflora is a low growing annual herb 5-15 cm long. Stems and leaves are sparsely pubescent. Leaves are 1-6 cm long with linear to oblanceolate leaflets 4-8 mm long. Sepals are pubescent without at the base and densely wooly pubescent within, from 8-14 mm long. Petals are white and range from 7-10 mm long. Filaments are 4-5 mm long with anthers less than 1 mm in length. Each flower produces 3-5 obovoid nutlets ranging from 3-4.5 mm long. Depending on the rains and temperature, this taxon can be found flowering from the beginning of March to mid-April.
Limnanthes floccosa ssp. grandiflora is morphologically similar to two other Limnanthes taxa found in the same geographical region, L. floccosa ssp. floccosa (woolly meadowfoam) and L. floccosa ssp. pumila (dwarf meadowfoam). Limnanthes floccosa ssp. grandiflora differs from these taxa in that it has sparsely pubescent stems and leaves. The stems and leaves of L. floccosa ssp. floccosa are usually densely pubescent while L. floccosa ssp. pumila is glabrous. In addition, L. floccosa ssp. grandiflora generally has larger flowers than either L. floccosa ssp. floccosa or L. floccosa ssp. pumila. Limnanthes floccosa ssp. grandiflora is often found growing sympatrically with L. floccosa ssp. floccosa. On average, L. floccosa ssp. grandiflora flowers 1-2 weeks later than L. floccosa ssp. floccosa, although the flowering seasons of both subspecies greatly overlap.
When to survey
Surveys for this species must be completed during its bloom time between the beginning of March and mid-April.
Limnanthes floccosa ssp. grandiflora is found near the wet inner edges of vernal pools. This is in contrast to Limnanthes floccosa ssp. floccosa, which usually prefers the drier outer edges of the same vernal pools. Limnanthes floccosa ssp. grandiflora is often found with other vernal pool species such as few-flowered collinsia (Collinsia sparsiflora), slender goldfields (Lasthenia californica), and white-flowered navarretia (Navarretia leucocephala).
Limnanthes floccosa ssp. grandiflora is currently, and historically, only known to exist near vernal pools in the Agate Desert region, north of Medford near White City.
Threats to Limnanthes floccosa ssp. grandiflora include invasive annual grasses and herbs, residential and industrial development of the Agate Desert region (which drain the vernal pools), off-road vehicle damage, and herbicide spraying.
A Draft Recovery Plan (pdf document, 5.30 MB) for listed species of the Rogue and Illinois Valleys was released in 2006 by U.S. Fish and Wildlife Service.
Did you know?
A closely related species to Limnanthes floccosa, Limnanthes alba (white meadowfoam), is currently cultivated as a crop plant in the Willamette Valley. Unlike common seed oils, species of the Limnanthes genus produce a very long chain seed oil with novel physical and chemical characteristics, making it extremely stabile at high temperatures and pressures. The only other known naturally occuring oil with similar qualities is sperm whale oil.
Current/Recent ODA projects
Evolutionary studies within the plant family Limnanthaceae
Arroyo, M.T.K. 1973. A taximetric study of infraspecific variation in autogamous Limnanthes floccosa (Limnanthaceae). Brittonia 25:177-191.
Mason, C.T. 1952. A systematic study of the genus Limnanthes R. Br. University of California Publication in Botany 25:455-512.
Meinke, R.J. 1982. Threatened and endangered vascular plants of Oregon: An illustrated guide. Unpublished report for the U.S. Fish and Wildlife Service, Region 1, Portland, Oregon. Oregon Department of Agriculture, Salem, Oregon.
Meyers, S.C. A molecular phylogeny of the meadowfoam family (Limnanthaceae). In prep.