Consequences of Some One-Off Events and Exclosure on a Red Grass (Bothriochloa Macra)-Wallaby Grass (Danthonia Eriantha) Pasture in the Central West of Nsw.

1997 ◽  
Vol 19 (2) ◽  
pp. 206 ◽  
Author(s):  
WS Semple ◽  
TB Koen ◽  
D Waterhouse
Keyword(s):  
Soil Erosion ◽  
Seedling Recruitment ◽  
Unexpected Result ◽  
Native Grasses ◽  
Exotic Grasses ◽  
Chloris Gayana ◽  
Exotic Grass ◽  
Chloris Gayana Kunth ◽  
Dominant Grasses ◽  
Herbicide Glyphosate

The effects of exotic grass introduction and cultivation, herbicide (glyphosate), burning or nil treatments on an exclosed red grass (Bothriochloa macra (Steud.) S.T. Blake) - wallaby grass (Danthonia eriantha Lindl.) pasture in the Central West of NSW were monitored for 3� years. The exotic grasses (Chloris gayana Kunth cv. Pioneer and Erogrostis curvula (Schrad.) Nees cv. Consol) established only in the cultivated plots but soil erosion also occurred in this treatment. Danthonia eriantha was killed by the glyphosate and cultivation treatments and had not re-established after 3� years. Cultivation also killed B. macra plants but limited recruitment subsequently occurred. Burning had little effect on the survival of either of the dominant native grasses. Seedling recruitment of the two dominant grasses was apparently minimal. However, where plants were not killed by the treatments, they expanded to fill some of the gaps created and D. eriantha appeared to be more competitive than B. macra. An unexpected result was the synchronised ripening of the Bothriochloa seedheads in the first summer following either burning or glyphosate application.

scholarly journals Habitat use by Collared Crescentchest (Melanopareia torquata) in a Cerrado in southeastern Brazil: implications for management

2012 ◽  
Vol 72 (4) ◽  
pp. 865-871 ◽  
Author(s):  
MF. Kanegae ◽  
G. Levy ◽  
SR. Freitas
Keyword(s):  
Habitat Use ◽  
Cattle Grazing ◽  
Southeastern Brazil ◽  
Native Grasses ◽  
Common Occurrence ◽  
Exotic Grasses ◽  
The Common ◽  
Exotic Grass ◽  
Indirect Relationship

The Collared Crescentchest (Melanopareia torquata) is a small insectivore endemic to the Cerrado. We examine the habitat use of this bird in a preserved Cerrado area in southeastern Brazil. Despite its occurrence in grassland with shrubs, the species used these areas less frequently than expected. The Collared Crescentchest mainly used areas of campo cerrado, but it was not recorded in a disturbed one. The common occurrence of exotic grass (U. decumbens) and cattle grazing may have brought about factors for its occurrence. However, the preference for native grasses may indicate an adverse indirect relationship against its occurence as there is competition between native and exotic grasses in the Cerrado. The presence of the Collared Crescentchest included the highest density of tall shrubs (>1 m) and native grasses. Conservation of the species should involve preserved areas of campo cerrado with a dominance of native grasses and tall shrubs.

Effects of flood irrigation and plant growth on two riverine soils

1959 ◽  
Vol 10 (4) ◽  
pp. 510 ◽  
Author(s):  
KP Barley ◽  
AL Tisdall
Keyword(s):  
Plant Growth ◽  
Exchangeable Sodium ◽  
Flood Irrigation ◽  
Nitrogen And Phosphorus ◽  
Rhodes Grass ◽  
Water Stable Aggregates ◽  
Electrolyte Content ◽  
Chloris Gayana ◽  
The Stability ◽  
Chloris Gayana Kunth

Two soils which contained significant proportions of exchangeable sodium were frequently irrigated during summer with water of low electrolyte content. When all vegetation was removed the soils became very unstable in water. When the natural vegetation was left intact the stability and structure of the soils did not deteriorate despite frequent irrigation. When the amount of vegetation was increased by sowing Rhodes grass (Chloris gayana Kunth) and supplying nitrogen and phosphorus the stability of the soil increased. After 8 years' growth of Rhodes grass the top inch of soil contained 30–40 per cent. of water-stable aggregates greater than 1 mm in diameter, compared with a content of 10–20 per cent. in virgin soil. Thus, the protective effect of the organic matter added to the soil by plant growth more than compensated for aggregate disruption caused by flood wetting or by a reduction in electrolyte content of the soil solution.

A study of two strains of Rhodes Grass (Chloris gayana Kunth.) and of Leucerne (Medicago sativa L.) as components of a mixed pasture at Lawes in South-east Queensland

1952 ◽  
Vol 3 (3) ◽  
pp. 277 ◽  
Author(s):  
CS Christian ◽  
NH Shaw
Keyword(s):  
Medicago Sativa ◽  
Growth Form ◽  
Live Weight ◽  
Small Population ◽  
Rhodes Grass ◽  
Weight Gains ◽  
Chloris Gayana ◽  
Medicago Sativa L ◽  
Chloris Gayana Kunth

The results of investigations with Rhodes grass and lucerne as components of sown pastures at Lawes in south-east Queensland are reported. Two strains of Rhodes grass, differing very markedly in growth form, rate of maturity, and other characteristics, were shown to be virtually of the same value when grazed by cattle under a system of intermittent grazing at a heavy rate of stocking. It was shown that lucerne could be maintained in a mixed pasture with Rhodes grass, and that the presence of a small population of lucerne, of a density of 2-4 plants per square yard, resulted in Increased growth of Rhodes grass and increased live-weight gains by the steers. Reasons for these increases are discussed.It is considered that the mixture, which can be expected to give improved grazing mainly during the summer months, has possibilities for large areas in south-east Queensland.

Pasture-scale vegetation predicts Dickcissel nest-site selection and success in native and exotic grass pastures

The Condor ◽  
2019 ◽  
Vol 121 (3) ◽  
Author(s):  
Adrian P Monroe ◽  
L Wes Burger ◽  
James A Martin
Keyword(s):  
Site Selection ◽  
Nest Site ◽  
Nest Survival ◽  
Nest Site Selection ◽  
Schizachyrium Scoparium ◽  
Beef Production ◽  
Exotic Grasses ◽  
Nest Sites ◽  
Exotic Grass ◽  
Tall Structure

Abstract Exotic grasses such as bermudagrass (Cynodon dactylon) and tall fescue (Schedonorus arundinaceus) are widely established across the southeastern United States as livestock forage, but their structure and management can limit avian reproductive success. Native warm-season grasses (NWSG) are promoted as sustainable forage alternatives. To examine nesting suitability for tall structure specialists such as Dickcissels (Spiza americana) we established an operational-scale study in northeastern Mississippi, USA, with 4 treatments along a gradient of beef production intensity. Treatments included grazed exotic forages, 2 grazed NWSG treatments including Indiangrass (Sorghastrum nutans) monoculture and NWSG polyculture of Indiangrass, little bluestem (Schizachyrium scoparium), and big bluestem (Andropogon gerardii), and an ungrazed NWSG polyculture treatment. We monitored 208 Dickcissel nests in 2011 and 2012 to evaluate effects of treatment, vegetation structure, fire ants (Solenopsis spp.), and arthropod prey biomass on nest-site selection and nest survival. Survival rates varied among treatments and increased with pasture-scale visual obstruction reading (VOR), being lowest among grazed exotic grass, intermediate in grazed NWSG, and highest in ungrazed NWSG. Although Dickcissels selected nest sites with greater VOR, we found little support for effects of nest-site vegetation on survival. However, nest survival was lower for nests in shrubs that also occurred in pastures with greater shrub cover, and selection for shrubs declined as pasture-scale VOR increased, suggesting a functional response in selection. We found little support for food availability influencing nest survival. These results suggest NWSG pastures increase Dickcissel nest success through greater pasture-scale VOR by reducing Dickcissel selection of shrubs for nest sites, and possibly by reducing predator efficiency. Incorporating NWSG into beef production systems while maintaining availability of tall vegetation could benefit Dickcissels and other tall structure specialists.

scholarly journals Threatened species in a threatened ecosystem: the conservation status of four Solanum species in the face of ongoing habitat loss

Oryx ◽  
2019 ◽  
Vol 53 (3) ◽  
pp. 439-449 ◽  
Author(s):  
Roderick J. Fensham ◽  
Jason Halford ◽  
Chris Hansen ◽  
Boris Laffineur ◽  
Billie Williams
Keyword(s):  
Habitat Loss ◽  
Conservation Status ◽  
Strong Association ◽  
Solanum Species ◽  
Individual Plant ◽  
Exotic Grasses ◽  
Tomato Species ◽  
The Face ◽  
Plant Densities ◽  
Exotic Grass

AbstractPlant biodiversity is threatened by habitat loss, fragmentation and invasion by exotic species, but the effects of these disturbances on individual plant species are rarely quantified. Since the 1950s, brigalow Acacia harpophylla forests in Australia have been extensively cleared and converted to pastures dominated by exotic grasses. Here we assess the habitat requirements, population numbers and threats for four poorly known bush tomato species, Solanum adenophorum, Solanum dissectum, Solanum elachophyllum and Solanum johnsonianum. Herbarium records and surveys demonstrated a strong association of all four species with brigalow habitat, although S. elachophyllum also occurred in other habitat. We derived historical and current population estimates from plant densities at current sites and the area of mapped brigalow habitat. Density estimates are imprecise because the survey data vary greatly, but the assessment indicates the populations of all four species have declined > 93%. Solanum dissectum and S. johnsonianum did not persist in cleared brigalow habitat, whereas S. adenophorum and S. elachophyllum had some capacity to persist in clearings. None of the species occur where the exotic grass cover is > 40%. Between 27% and 57% of the records of the four species are in brigalow remnants with a high edge-to-area ratio or open canopy (< 50% cover), making them highly vulnerable to invasive grasses. We recommend the categorization of S. dissectum and S. johnsonianum as Critically Endangered, S. adenophorum as Vulnerable and S. elachophyllum as Near Threatened.

Germination characteristics of several grass species as affected by limiting water potentials imposed through a cracking black clay soil

1982 ◽  
Vol 33 (2) ◽  
pp. 223 ◽  
Author(s):  
LA Watt
Keyword(s):  
Water Availability ◽  
Clay Soil ◽  
Grass Species ◽  
Native Grasses ◽  
Exotic Grasses ◽  
Germination Ecology ◽  
Black Clay ◽  
Water Potentials ◽  
Germination Characteristics ◽  
Wilting Point

The effects of limiting water potentials on the germination characteristics of 12 grasses were studied. Germination proper was prevented in all species at water potentials well short of wilting point and different species had their germination prevented at different potentials. Generally the native grasses required wetter conditions to germinate than the exotic grasses, although there were some exceptions. A partial germination condition, caused by limited water availability, occurred to differing degrees amongst the species. Some species retained their viability when desiccated in the partially germinated condition, but other species lost their viability. The partial germination phenomenon appears important to the germination ecology of some species but not to others.

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