Euphorbia strictior Holzinger

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Family: Euphorbiaceae

Synonyms: Tithymalopsis strictior (Holz.) Woot. & Standl.

Distribution: The type locality is Oldham County, Texas.

Huft (1979) provides a disappointing written description of the plant's distribution by stating that it "is much more restricted in range [than Euphorbia wrightii], occurring in the high plains in three counties of the Texas panhandle [eastern side] and three counties in adjacent New Mexico"; his map indicates that he saw specimens that came from several miles north and south of the Canadian River in the Tucumcari area and one specimen from as far south as perhaps the Clovis area (Curry County). Naumann (1986) lists six counties in New Mexico (Chavez, Curry, Harding, Quay, Roosevelt, and San Miguel) and four counties in Texas (Crockett, Deaf Smith, Oldham, and Smith) in which this plant is known to occur.

Habitat: Plains and hills (Woot. & Standl. 1915); often in disturbed soils in rights-of-way, sandy limestone soils, in PJ woodland or juniper savannah (Sivinski 1997); infrequent in sandy areas of the short grass plains, 900-1,400 m (3,000-4,500 ft.) (New Mexico Native Plant Advisory Committee 1984).

Plants Seen or Cited: Huft (1979) lists no exsiccata. There are several specimens at UNM.

Quay county:
1. A. Nels. sn. 19 and 20 June 1931. Tucumcari roadside.
2. A. Lake. sn. 25 June 1936. ½ mi northwest of Experiment Station, Tucumcari
3. Shinners. sn. 8 August 1955, 8 mi sw of Tucumcari
4. Hutchins. 8915 & 8919. 13 June 1980. Highway 39, 14 south of Ute Creek

San Miguel county:
5. Sivinski. 2609. 14 September 1993. 22 mi east of Conchas on highway 104, MP 97, locally common (extreme southeastern edge of San Miguel county near Tucumcari)

Other records from sources other than specimens at UNM:

Quay county:
6. Tucumcari Mountain and Nara Visa (Woot. & Standl. 1915)
8. Ute Lake (observation by Barlow-Irick 1997).

Discussion: This plant is currently on the L2 list (Sivinski & Lightfoot 1995). Although it is apparently endemic to east-central New Mexico and adjacent Texas, there is ample evidence that it is more common than previously thought and that it seems to be in no apparent danger of eradication. I suggest that it be moved from L2 to L4.(Too common in its range in New Mexico and Texas).

Literature cited:

Barlow-Irick, P. 1997. Personal communication.

Correll, D.S. and M.C. Johnston. 1979. Manual of the vascular plants of Texas, second printing. The University of Texas at Dallas, Richardson, TX. (page 966)

Huft, M.J. 1979. A monograph of Euphorbia section Tithymalopsis. Unpublished PhD dissertation. University of Michigan.

Naumann, T.S. 1986. Status report on Euphorbia strictior. The Nature Conservancy and US Fish and Wildlife Service, Albuquerque, NM.

New Mexico Native Plants Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. University of New Mexico Press, Albuquerque. (pages 136-137, with illustration)

Sivinski, R. and K. Lightfoot. 1995. Inventory of rare and endangered plants of New Mexico. New Mexico Forestry and Resources Conservation Division; Energy, Minerals and Natural Resources Department, Santa Fe.

Sivinski, R. 1997. Email communication.

Wooton, E.O. and P.S. Standley. 1915. Flora of New Mexico. Contributions from the United States National Herbarium, Smithsonian Institution, Government Printing Office, Washington, D.C. (page 396).

Information Compiled By: David L. Bleakly, 1998