Eragrostis curvula
Eragrostis curvula, commonly known as weeping lovegrass or African lovegrass ,is a perennial grass native to South Africa. Eragrostis curvula has been introduced to North America and Australia since the 20th century and is now widespread. It favors areas that have been recently disturbed such as after fires or overgrazed grasslands but can be found: alongside highways, railway lines, open woodlands, pastures, and coastal shores.
| Kingdom: | Plantae |
| Order: | Poales |
| Family: | Poaceae |
| Genus: | Eragrostis |
Description
Eragrostis curvula can have a variable appearance ranging from 120 cm to 180 cm in height. The plant grows tufts of narrow leaves that can reach 1 ft in diameter and are bluish-green in color. The leaves can grow up to 2 ft [1] and clump together in a drooping position at the base of the plant. The blades of each leaf, roll inwards [2] and have a rough texture that are attached to hairless stems. The leaves get narrower as they reach the tip of the branch, where it appears lighter and curled [3].
Root System
The root system of Eragrostis curvula is dense and fibrous, reaching up to 13 ft below the soil surface vertically, and up to 3 ft laterally[4] where they typically fill the entire space. Roots can grow 2 inches a day and create thick mats that aid in erosion control. The primary roots are the first roots to sprout from the seedlings and grow straight down with 30 - 60 rootlets per inch. The large root system makes it suitable for dryer soils such as in desert areas. It's hardiness and drought-tolerance also makes it easy to establish alongside highways or roadsides that have high salinity soil. When temperatures consistently reach above 50° F, roots can start to grow rapidly.
Growth
The inflorescence of Eragrostis curvula starts as a tightly closed panicle but slowly opens up as it matures. At the base of the panicle, branches start to spread out that have green-grey or purple flower spikelets which turn paler in color as they flower[2]. The flower spikelets break open for seed dispersal which happens in the late summer/early fall season.
Reproduction
Eragrostis curvula reproduces through seed dispersal via animals, wind, and vehicles [3]. Seeds are small in size (<1 cm) and have an ovular shape that can be a yellow-brown in color. As they have no appendages, seeds are unable to be carried far and rely on winds to carry them short distances. This also prevents them from burrowing into the soil, as they are usually found within the top 2 inches of soil. Panicles can produce 300 - 1000 seeds, with factors such as high temperatures, high moisture levels, and low humidity increasing seed production [4]. Seedlings are able to establish themselves quite easily and can rapidly increase ground cover. Favorable conditions for successful seedling establishment vary, however they do prefer moist soil but not extremely moist.
Impact
When spread to non-native areas, Eragrostis curvula can outcompete native vegetation, especially in pastures. Cattle and sheep can only feed on young plants [5] but is unpalatable and reduces the quality of pastures. After consumption, the tussock is left, which will shade out emerging vegetation. It is considered an 'aggressive' species [4] since it can reduce the growth of Eragrostis intermedia (native plains lovegrass) among other native shrubs and typically sprouts 2 - 4 weeks before native plants. It's also susceptible to fire because of its density and can intensify natural wildfires. It has spread alongside the Colorado River [6] which has called for management amongst concerns that it could spread rapidly if left alone.
Distribution in the US
Eragrostis curvula can tolerate highly acidic soils with heavy metal levels [4]. This has allowed it to be planted near mine sites in Tennessee, Virginia, and Kentucky, where they provided substantial ground cover. In New York, Eragrostis curvula was planted alongside highways in Long Island by the Department of Transportation where it's become established since 2000. Vermont has also used Eragrostis curvula to restore degraded sand dune sites after multiple planting failures.
- ↑ Eragrostis curvula, North Carolina Extension Gardener Plant Toolbox, https://plants.ces.ncsu.edu/plants/eragrostis-curvula/ Accessed 07 May 2023.
- ↑ 2.0 2.1 Eragrostis curvula, Weeds of Australia. 2016 https://keyserver.lucidcentral.org/weeds/data/media/Html/eragrostis_curvula.htm. Accessed 07 May 2023
- ↑ 3.0 3.1 African lovegrass Eragrostis curvula. 2016. . Pages 1–20. Invasive plant risk assessment, Department of Agriculture and Fisheries, Biosecurity Queensland.
- ↑ 4.0 4.1 4.2 4.3 Gucker, Corey L. 2009. Eragrostis curvula. In: Fire Effects Information System. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. Available: https://www.fs.usda.gov /database/feis/plants/graminoid/eracur/all.html [2023, May 7]
- ↑ EPPO. 2009. Mini data sheet on Eragrostis curvula (Poaceae)
- ↑ Stevens, Lawrence E.; Ayers, Tina. 2002. The biodiversity and distribution of exotic vascular plants and animals in the Grand Canyon region. In: Tellman, Barbara, ed. Invasive exotic species in the Sonoran region. Arizona-Sonora Desert Museum Studies in Natural History. Tucson, AZ: The University of Arizona Press; The Arizona-Sonora Desert Museum: 241-265.