Name:
Eragrostis lehmanniana - Bromus rubens - Brassica tournefortii Warm Desert Ruderal Grassland Group
Reference:
NatureServe Biotics 2019
Description:
This broadly defined ruderal group occurs in Arizona and northern Mexico and elsewhere in the Desert Southwest. It includes all desert scrub with an exotic species-dominated understory (>90% relative cover) in the herbaceous layer as well as exotic-dominated herbaceous stands. These open to dense grasslands and forblands are composed of either exotic annual or biennial grasses or forbs with low cover of perennial species (<10% absolute cover) or stands with a significant perennial herbaceous layer (>10% absolute cover) strongly dominated by exotics (>90% relative cover) with or without annuals and biennials present to dominant. Characteristic understory species include <i>Brassica nigra, Brassica tournefortii, Bromus madritensis, Bromus rubens, Cynodon dactylon, Eragrostis lehmanniana, Erodium cicutarium, Schismus arabicus, Schismus barbatus</i>, and <i>Sorghum halepense</i> with little native composition remaining. Other woody species may include <i>Calliandra eriophylla, Gutierrezia sarothrae</i>, or <i>Isocoma tenuisecta</i>. <i>Gutierrezia microcephala</i> is abundant in some stands. Remnant native desert grasses may be present with low cover. Other common herbaceous species include <i>Allionia incarnata, Ambrosia confertiflora, Boerhavia erecta, Mollugo verticillata, Cylindropuntia versicolor, Panicum hirticaule, Polygala barbeyana, Proboscidea parviflora</i>, and <i>Phemeranthus aurantiacus</i>. The native annual forb <i>Amaranthus palmeri</i> often codominates. This desert grassland and shrubland group occurs in southeastern Arizona on alluvial fans, ridges, hills and valley floors. The elevation range is 960-1100 m (3150-3600 feet). Climate is warm, semi-arid to arid continental. Mean annual precipitation ranges from 22-28 cm, but can vary greatly from year to year. Drought is not uncommon. Sites occur on gentle to moderate slopes. Substrates are variable but are often well-drained sandy loam.
Accession Code:
urn:lsid:vegbank.org:commConcept:40318-{833830D3-EBE7-443B-A2DE-C6B50C272559}
Plot-observations of this Community Concept:
0
|
