Lappula occidentalis (S. Wats.) Greene
by Marissa Joe, Native Plants of Arizona 2007
Common names: flatspine stickseed (1,2), desert stickseed (2), western stickseed (4), western sticktight (5), white stickseed (7), flat-spine sheepburr (8).
Family: Boraginaceae (1,3)
Synonymy: Lappula redowskii (1,2) and Lappula texana (2).
Etymology: “Lappula” with small burrs (refers to nutlet); “occidentalis” means of the west.
Identification
Growth form: Herbaceous with stems having small stiff hairs (2).
Roots: Tap rooted (6).
Stem: Stems 10-80 cm tall (1) with small stiff hairs (2,7). Many branches above the middle (1).
Leaves: Numerous alternate leaves(1,7), upper leaves are sessile and 1-2 mm long, lower blades are petioled and up to 6 cm long; basal leaves often deciduous (1). Leaves are lanceolate to oblanceolate with hairs on them and ciliated margins (2).
Inflorescence/flowers: Inflorescence coiled like a scorpion tail (2). Flowers have inconspicuous corollas that are light blue to nearly white (1,5).
Fruit: 1- 4 nutlets (5). Nutlet with marginal prickles in a single row, prickles often swollen and confluent toward the base (1).
Similar species: There are two varieties of Lapula occidentalis found in Arizona: var. cupulata is mainly found in the southwestern United States and var. redowskii is found throughout the range. Lappula squarrosa has nutlets with marginal prickles in at least 2 rows and prickles that are slender and not confluent at the base as in L. occidentalis (1).
Ecology
Life history: herbaceous annual (2).
Native/introduced: Native (1,3).
Photosynthetic pathway:
Phenology: Flowers March to September.
Distribution: Widely distributed to 8,500 feet. Dry to moderately moist, sunny, usually disturbed sites, roadsides, and overgrazed areas (1). Easily distributed due to burrs on nutlet sticking to passersby (5). In Arizona found in all counties. Also found throughout the Western United States, and a few eastern states such as Maine and Vermont (8).
Uses
The Navajo make a poultice for insect bites and other skin irritations (1).
References
1. Ecological Restoration Institute. 2005. Plants of Northern Arizona Forest. Not published.
2. Hogan P., Huisinga K., Kampe K. 2005. An Annotated Catalog of the Native and Naturalized Flora of Arizona. Arizona Ethnobotanical Research Association. Flagstaff, Arizona.
3. USDA, NRCS. 2007. The PLANTS Database (http://plants.usda.gov, 12 November 2004). National Plant Data Center, Baton Rouge, LA 70874-4490 USA..
4. Retrieve [October 26, 2007], from the Integrated Taxonomic Information System (ITIS) on-line database (http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=528678).
5. Burrill L.c., cuden D.W., Dewey S.A., Lee R.D, Nelso B.E., Parker R., Whitson T.D. Weds of the West. The Western Society of Weed Science. The Western United States Land Grant Universities Cooperative Extension Services. Jackson, Wyoming.
6. Cronquist A., Holmgren A.H., Holmgren N.H., Holmgren P.K., Reveal J.L. 1984. Intermountian Flora. The New York Botanical Garden. Bronx, New York.
7. Retrieved [October 27, 2007], from Wildflowers of Tucson, Arizona, (http://www.fireflyforest.com/flowers/whites/white35.html).
8. Retrieved [October 27,2007], from (http://zipcodezoo.com/Plants/L/Lappula_occidentalis.asp#).
