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Monocotyledons / Monocotiledóneas
Panicum obtusum
EOL Text
Vine-mesquite is an indicator of moist microsites in arid environments.
It is found along streams, roads, gullies, swales, playas, and arroyos
[2,5,10,16].
Soils: Vine-mesquite occurs in the Alfisol, Entisol, Inceptisol,
Mollisol, and Vertisol soil orders [30].
Climate: Vine-mesquite inhabits areas where the winters are short and
mild, and the summers are characterized by long periods of high
temperatures [4]. The average annual precipitation is 10 to 18 inches
(25-45 cm) [8].
Elevation: Vine-mesquite generally grows in an elevational range of
1,000 to 6,000 feet (305-1,800 m) [24].
More info for the term: graminoid
Graminoid
Hopia obtusa is a species of grass commonly known as Vine Mesquite. This plant was treated as Panicum obtusum until recently when more molecular and genetic material revealed new information about it.[1]Hopia obtusa is now placed in the monotypic genus Hopia.[1]
Description[edit]
Hopia obtusa is a perennial grass with stems up to 20 to 80 centimetres (7.9 to 31.5 in) tall. It has long, creeping rhizomes or shallow rhizomes with swollen, villous nodes. The culms are usually in small, compressed, glaucous clumps that are either erect or decumbent. Nodes are hairy lower on the plant but glabrous higher up. The sheath is pubescent to pilose lower on the plant but glabrous higher up. It has membranous truncate, irregularly denticulate ligules that are 0.2–2 millimetres (0.0079–0.0787 in) big. Leaf blades are 3–26 cm (1.2–10.2 in) long and 2–7 mm (0.079–0.276 in) wide; they are ascending, firm, glaucous, sparsely pilose near the base, often scabrous on the margins, and involute towards the tips. The panicles are 5–15 cm (2.0–5.9 in) long and 0.8–1.5 cm (0.31–0.59 in) wide. The panicle has 2 to 6 spikelike, erect, puberulent, and 3-angled branches. The ultimate branchlets are one-sided. The pedicels are paired and congested. Some spikelets are on short pedicels that are 0.1–1 mm (0.0039–0.0394 in), while others are on longer pedicels 1.5–2.5 mm (0.059–0.098 in). Spikelets are 2.8–4.4 mm (0.11–0.17 in) long, ellipsoid, terete to slightly laterally compressed, glabrous, and obtuse. The lower glumes are about 3/4 as long as the spikelet and are 5- or 7-veined. Upper glumes and lower lemmas equal the spikelet's length and are 5– to 9-veined. The lower florets are staminate with its lower paleas 2.5–3.5 mm (0.098–0.138 in) long. The upper florets are puberulent at the bases and apices. Flowering is from May through October.[2]
Habitat[edit]
Hopia obtusa grows in seasonally wet sand or gravel, especially on stream banks, ditches, roadsides, wet pastures, and rangeland. Its range extends from the southwestern United States to central Mexico.[2]
References[edit]
- ^ a b Fernando O. Zuloaga, Liliana M. Giussani & Osvaldo Morrone (2007). "Hopia, a new monotypic genus segregated from Panicum (Poaceae)". Taxon 56 (1): 145–156. JSTOR 25065745.
- ^ a b "Hopia description". Intermountain Herbarium. Utah State University. Retrieved November 29, 2010.
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| Source | http://en.wikipedia.org/w/index.php?title=Hopia&oldid=636282827 |
More info on this topic.
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
More info for the term: shrub
K023 Juniper - pinyon woodland
K024 Juniper steppe woodland
K027 Mesquite bosque
K031 Oak - juniper woodlands
K032 Transition between K031 and K037
K037 Mountain-mahogany - oak scrub
K039 Blackbrush
K040 Saltbush - greasewood
K041 Creosotebush
K042 Creosotebush - bursage
K044 Creosotebush - tarbush
K045 Ceniza shrub
K053 Grama - galleta steppe
K054 Grama - tobosa prairie
K057 Galleta - threeawn shrubsteppe
K058 Grama - tobosa shrubsteppe
K059 Trans-Pecos shrub savanna
K060 Mesquite savanna
K061 Mesquite - acacia savanna
K062 Mesquite - live oak savanna
K065 Grama - buffalograss
K069 Bluestem - grama prairie
K070 Sandsage - bluestem prairie
K071 Shinnery
K076 Blackland prairie
K084 Cross Timbers
K085 Mesquite - buffalograss
K086 Juniper - oak savanna
K087 Mesquite - oak savanna
K088 Fayette prairie
The site is level to undulating with a few slopes greater than 20
percent. Elevation is 1,205 to 1,405 feet (365-425 m). The soils are
sandy loams which are slowly to moderately permeable. Moisture
retention is moderate, and soils are fertile enough to provide good
grass production. The limestone bedrock is cracked, forming deep
pockets capable of supporting deep-rooted grasses. The average
precipitation is 24 to 28 inches (60-70 cm) per year. During the course
of the study the precipitation varied from a near normal year in 1970,
with 23 inches (58.2 cm) falling from November 1969 to May 1970, to a
dry year in 1971, with 6.5 inches (16.5 cm) falling from November 1970
to May 1971.
More info on this topic.
This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):
FRES29 Sagebrush
FRES30 Desert shrub
FRES31 Shinnery
FRES32 Texas savanna
FRES33 Southwestern shrubsteppe
FRES35 Pinyon - juniper
FRES38 Plains grasslands
FRES39 Prairie
FRES40 Desert grasslands
Spring 1970/light
Spring 1971/moderate
vine-mesquite
panic grass
Vine-mesquite is commonly found in the understory of soapberry (Sapindus
saponaria), gray oak (Quercus grisea), juniper (Juniperus spp.), and
mesquite (Prosopis spp.) communities [4,28,29,30]. In the understory
vine-mesquite is associated with curlymesquite (Hilaria belangeri),
side-oats grama (Bouteloua curtipendula) [9], buffalograss (Buchloe
dactyloides), Indian ricegrass (Oryzopsis hymenoides), and galleta
(Hilaria jamesii) [7].
Vine-mesquite is listed as an indicator or dominant species in the
following vegetation and community type classifications:
Zonation of herbaceous vegetation associated with honey mesquite in
northcentral Texas [45]
Riparian plant communities of the Fort Bayard watershed in southwestern
New Mexico [28]
Woodland communities and soils of Fort Bayard, southwestern New Mexico [29].