Wildlife, Animals, and Plants
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BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Echinochloa crus-galli | Barnyard Grass
GENERAL BOTANICAL CHARACTERISTICS :
Barnyard grass is an introduced, nonrhizomatous, warm-season annual.
Stems may be solitary or in small tufts, erect or reclining at the base,
up to 6.6 feet tall (2 m) [16,28,39,52,80]. Leaves are flat, 4 to 12
inches (10-30 cm) long and 0.2 to 0.6 (5-15 mm) inch wide [18,19,27,46].
The panicle is 2 to 8.4 inches (5-21 cm) long, upright or nodding
[19,46,68]. Barnyard grass has a fibrous root system [39,49].
RAUNKIAER LIFE FORM :
Therophyte
REGENERATION PROCESSES :
Barnyard grass reproduces by seed. It is self-pollinating [51] and a
prolific seed producer [28,44,68]. A healthy plant can produce from
750,000 to one million seeds [44]. Barnyard grass seed is water
dispersed [1]. Seed viability in soil is variable [10,44]. In
Stoneville, Mississippi, in 1972, a 50-year study on longevity of buried
seed of barnyard grass was initiated. Seed viability was 1 percent
after burial for 2.5 years; less than 6 percent of seed survived 6
months or longer [10]. However, according to Dawson [8], barnyard grass
seed may be viable in the soil for up to 13 years. In another study by
Mitich [44], seed viability of barnyard grass was 100 percent after 6 to
8 years of dry storage in irrigated sandy loam soil, and all seed was
nonviable after 15 years. Watanabe [79] found that barnyard grass seed
germination rate was 27 percent after burial for 6 months and 3 percent
after burial for 6.5 years. Barnyard grass seed germinates over a wide
temperature range, 55 to 104 degrees Fahrenheit (13-40 deg C), with
optimum germination occurring from 68 to 86 degrees Fahrenheit (20-30
deg C) [53,62].
The buoyancy and hence dispersal by water of barnyard grass seeds is
probably influenced by their weight. A survey of seed weight [1]
demonstrated that seeds of E. crus-galli var. oryzicola were on the
average 2 to 3 times heavier than those of E. crus-galli var.
crus-galli. The lighter seeds of E. crus-galli var. crus-galli
exhibited greater buoyancy, with approximately 50 percent of seeds
remaining afloat after 4 to 5 days in water. In contrast, 95 percent of
E. crus-galli var. oryzicola seeds had sunk after 5 days. Decay of
dormancy in E. crus-galli var. oryzicola is more rapid than in E.
crus-galli var. crus-galli following dry storage and burial in soil.
SITE CHARACTERISTICS :
Barnyard grass is widespread in fields, waste places, ditches, marshes,
wet meadows, floodplains and along lakeshores and streambanks
[18,20,33,38,39]. It is locally common in floodplains, riverbottoms,
and seasonally wet habitats [1,63,80], but also occurs in drier habitats
[24]. Barnyard grass is most often found on disturbed, generally
nonsaline soils [25,53,63], but grows on a variety of soil types
[38,53]. Echinochloa crus-galli var. crus-galli is generally absent
from sites that have greater than 12 inches (30 cm) of standing water
for more than 4 weeks at a time [42,63]. It occurs in shallow water or
after drawdown [63]. Barnyard grass tolerates poor drainage and
flooding, but not severe drought [7,31,44,60].
In California, the two varieties of barnyard grass differ in habitat
preference and colonizing ability. Echinochloa crus-galli var.
crus-galli is a cosmopolitan weed of wet, disturbed ground and occurs in
shallow water around the periphery of rice fields. Echinochloa
crus-galli var. oryzicola is a crop mimic that is found primarily in
permanently flooded cultivated rice fields [1].
Elevations of barnyard grass are as follows:
feet meters
Arizona 150-7,000 45-2,100 [27]
California <4,950 <1,500 [20]
Colorado 4,500-7,500 1,350-2,250 [19]
Kansas 3,370-4,675 1,021-1,417 [38]
Montana 2,800-3,300 840-1,000 [86]
South Dakota 1,940-2,025 587- 614 [71]
Texas 7,400 2,320 [21]
Utah 2,705-7,045 820-2,135 [80]
Wyoming 3,700-5,100 1,110-1,530 [86]
SUCCESSIONAL STATUS :
Barnyard grass is a pioneer species that readily invades disturbed sites
[63,68]. It is found most often in open, unshaded areas [25,44], and is
intolerant of dense shade [44]. Barnyard grass invades South Dakota
rangelands and rapidly colonizes overflow and subirrigated range sites
that have been denuded or disturbed in Nebraska [37,68]. In Idaho,
barnyard grass is an increaser species on periodically flooded sites
along streams [58]. At a restoration prairie site in Ohio, barnyard
grass established at the edge of an ephemeral pond that is subject to
periodic flooding and drying [7]. In an old-field succession deciduous
forest in southwestern Ohio, barnyard grass was found growing in a
2-year-old stand, but was not present in stands 10, 50, 90, or 200 years
old [56,74].
SEASONAL DEVELOPMENT :
Barnyard grass flowering dates for several states are as follows:
Arizona July-Sept [27]
California July-Oct [46]
Colorado Aug-Sept [86]
Florida all year [84]
Illinois Aug-Oct [45]
Montana June-Oct [86]
Nebraska Aug-Sept [61]
North Carolina July-Oct [52]
North Dakota July 15 [65]
South Carolina July-Oct [52]
West Virginia Aug-Oct [67]
Wyoming Aug-Oct [86]
Great Plains June-Sept [16]
Related categories for Species: Echinochloa crus-galli
| Barnyard Grass
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