A survey of the natural pastures of the Trangie District, New South Wales, with particular reference to the grazing factor.

1953 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
EF Biddiscombe
Keyword(s):  
Perennial Grass ◽  
Grazing Intensity ◽  
Basal Area ◽  
Grazing Pressure ◽  
Perennial Grasses ◽  
Forage Production ◽  
South Wales ◽  
Wide Range ◽  
Grazing Intensities ◽  
Summer Maximum

The Trangie district has a rainfall of 1,750 points with a slight summer maximum, a high relative variability of rainfall, and high summer temperatures. Disclimax pasture communities produced by a range of sheep grazing intensities operative during the past 20-30 years are described. On light soils ungrazed pasture comprises a wide range of perennial grasses. Light grazing (1 sheep per 2 acres) gives increased dominance by Stipa fulcata. With successive increases in grazing pressure Chloris acicdaris and Stipa setacea become conspicuous in turn, only to be virtually replaced by Chloris trumata as grazing intensity reaches 1 sheep per 0.5 acre. On heavy soils Stipa aristiglumis is dominant under light grazing. With increased rate of stocking, first Sporobolus caroli and then Stipa setacea gain dominance. At the highest stocking rates all these species are largely replaced by Chloris truncata. Throughout the sere the number of species is far more restricted than on the light soils. The striking feature of these results is that though botanical composition of the perennial grass component on light and heavy soils respectively is vastly different under light grazing, it becomes similar under heavy grazing and almost identical under severe grazing. Degenerative changes common to pastures of both soil groups under increasing grazing pressure are the decline in density and basal area of the perennial grass component, the greater population of winter and summer annuals, and the declining contribution of perennial grasses to green forage production in the spring. The basis of these findings is firstly the measurement of basal area, density and yield of perennial grasses, and density and yield of annual species in pastures of varying stocking history, and secondly, the measurement of pasture composition in relation to increasing distance from watering points.

Changes in the Quantitative Floristics in Some Astrebla Spp. (Mitchell Grass) Communities in South-Western Queensland in Relation to Trends in Seasonal Rainfall

1981 ◽  
Vol 29 (5) ◽  
pp. 533 ◽  
Author(s):  
DM Orr
Keyword(s):  
Relative Abundance ◽  
Perennial Grass ◽  
Grazing Pressure ◽  
Perennial Grasses ◽  
Seasonal Rainfall ◽  
Individual Species ◽  
Botanical Composition ◽  
Basal Cover ◽  
Wide Range ◽  
Annual Grasses

Seasonal changes in the quantitative floristics at a wide range of Astrebla grassland sites in south-western Queensland were monitored between 1972 and 1980 with a wheel point apparatus. Changes in the floristics were measured in terms of both relative abundance and basal cover. A large increase in the relative abundance of perennial grasses, particularly Aristida latifolia, Astrebla spp. and Dichanthium sericeum, occurred between 1972 and 1976. This increase was at the expense of annual grasses and forbs which declined in both relative abundance and number of genera present. The relative abundance of perennial grasses declined between 1978 and 1980 and this was associated with a large increase in the forbs such as Daucus glochidiatus and Plantago spp., particularly at southern sites. The contribution of annual grasses to botanical composition remained low throughout the period. Total basal cover differed between years although these differences were not significant. As perennial grass, particularly Astrebla spp., was the major vegetation component of total basal cover, changes in the latter were associated mainly with changes in the basal cover of Astrebla spp. Changes in the contribution of individual species to total basal cover were related to changes in the relative abundance of those species. Changes in botanical composition in Astrebla grassland may be influenced more by trends in seasonal rainfall than by grazing pressure.

Effects of Rabbit and Kangaroo Grazing on Two Semi-Arid Grassland Communities in Central-Western New South Wales

1989 ◽  
Vol 37 (5) ◽  
pp. 375 ◽  
Author(s):  
JH Leigh ◽  
DH Wood ◽  
MD Holgate ◽  
A Slee ◽  
MG Stanger
Keyword(s):  
Species Composition ◽  
New South ◽  
New South Wales ◽  
Grazing Intensity ◽  
Grazing Pressure ◽  
Present Species ◽  
Grass Species ◽  
South Wales ◽  
Native Grassland ◽  
Wide Range

The effects of rabbits and kangaroos, and rabbits alone, on the biomass and species composition of a native grassland dominated by Stipa nitida/nodosa, Danthonia caespitosa and Aristida contorta, and a grassland dominated by the exotic species Hordeum glaucum, Vulpia spp., Medicago laciniata and the native Erodium crinitum growing at Yathong Nature Reserve in central New South Wales was monitored between 1979 and 1985. Rabbits generally favoured the grassy component; kangaroos also favoured grasses but less so. Changes in non-grass species composition due to grazing was generally insignificant. Changes in species composition due to seasonal differences in rainfall was highly significant. No new species appeared on plots exclosed from grazing for 10 years, suggesting that the grazing by livestock, rabbits, and kangaroos in the past has determined the present species composition. The annual biomass consumption by rabbits averaged over 6 years was 100-200 kg ha-1, which is equivalent to reducing the carrying capacity by one sheep for every 2-4 ha rabbit-infested area. In the native grassland the spatial pattern of rabbit grazing, as indicated by faecal pellet distribution, biomass removal, and percentage of 'unpalatable' species in the pasture, shows greatest grazing pressure to be within 50 m of the warren, grazing intensity dropping off from there to 300 m the greatest distance studied. From the start of the study 'palatable' species, especially grasses, were at their lowest density within 50 m of the warren; this appeared to be a historical effect of grazing. No patterns were discernible in the pasture dominated by introduced species. Little change in species composition of these grasslands can be expected under a wide range of grazing pressure, except close to rabbit warrens.

Range condition assessment in bladder saltbush (Atriplex vesicaria) communities.

1982 ◽  
Vol 4 (2) ◽  
pp. 41 ◽  
Author(s):  
AD Wilson ◽  
GJ Tupper ◽  
DJ Tongway
Keyword(s):  
Soil Fertility ◽  
Canopy Cover ◽  
Grazing Intensity ◽  
Soil Surface ◽  
Community Change ◽  
Available Phosphorus ◽  
Forage Production ◽  
South Wales ◽  
Wide Range ◽  
Texture Contrast

Factors contributing to changes in the condition of saltbush communities (Atriplex vesicaria) in the Riverine Plain and Barrier Range regions of New South Wales were measured under a variety of seasonal situations. Groups of eight plots, representing a range of past grazing intensity, were established at each location and measurements were made of species biomass, canopy cover and frequency, forage availability and soil fertility. In both regions, high grazing intensity was characterized by the elimination of the saltbush (A. vesicaria) and an increase in other species, such as Astrebla (mitchell grass), Sclerolaena spp. (copperburrs), annual Atriplex spp. and a wide range of ephemeral species. These changes were best characterized by canopy cover measurements which gave a quantitative assessment of the vegetation changes (in contrast to frequency) and gave values that were less seasonally variable than biomass. Up to 83 species were recorded, but these were aggregated into approximately 9 groups to simplify the collection and analysis of data, without loss of information. On the Barrier Range site, the A. vesicaria was replaced by palatable species, so that there was little loss of overall forage production. Similarly, there was little evidence of loss of soil fertility, as measured by various measures of soil nitrogen, available phosphorus and organic carbon. There was no erosion on these sites, although this may occur on other saltbush communities that grow on texture contrast soils. On the basis of these results, four separate indices of condition are proposed for saltbush communities. These are based on the measurement in the growing season of the canopy cover of major perennial and biennial species or species groups. They are (i) the relative cover of A. vesicaria (the major observable change in these communities), (ii) the relative total cover of desirable forage species (an index of forage productivity), (iii) percentage similarity (an index of community change for conservation purposes), and (iv) the relative area of eroded soil surface.

Safe pasture utilisation rates as a grazing management tool in extensively grazed tropical savannas of northern Australia

2008 ◽  
Vol 30 (3) ◽  
pp. 305 ◽  
Author(s):  
L. P. Hunt
Keyword(s):  
Perennial Grass ◽  
Grazing Intensity ◽  
Growing Season ◽  
Perennial Grasses ◽  
Management Tool ◽  
Management Approach ◽  
Tropical Savannas ◽  
Forage Production ◽  
Stocking Rates

The concept of safe pasture utilisation rates is frequently promoted as a tool for use in setting livestock numbers in perennial grass pastures in northern Australia’s tropical savannas to achieve a grazing intensity that is ecologically and economically sustainable. However, recommended pasture utilisation rates have been defined and applied in several ways, and this has led to some confusion among managers, researchers and advisers about their appropriate use. In order to reduce this confusion, this paper reviews the ecological basis and use of safe pasture utilisation rates as a management tool, concentrating on two common ways (i.e. strategic and tactical) in which they are applied. The main objective of both approaches is to limit the intensity of grazing of perennial grasses during the growing season when they are most sensitive to defoliation. When used in a strategic way, safe pasture utilisation rates provide an indication of long-term safe stocking rates that will avoid pasture deterioration in most years. Alternatively, they are used in a tactical sense to adjust stocking rates to track forage production, usually on an annual basis. Using the tactical approach, stocking rates are set at the end of the growing season in order to use a ‘safe’ proportion of the standing forage available at that time during the subsequent 12 months. Thus, stocking rates for one growing season are based on the quantity of forage available at the end of the previous growing season. In areas with high year-to-year variability in pasture growth this may lead to overgrazing during the growing season. This paper concludes by suggesting several strategies to better manage pasture utilisation levels under a tactical management approach to ensure that palatable perennial grass populations persist in the long term. A call is also made for researchers and land management advisers to be clear in the way recommended safe pasture utilisation rates are defined and intended to be used.

Satellite derived maps of pasture growth status: association of classification with botanical composition

1997 ◽  
Vol 37 (5) ◽  
pp. 547 ◽  
Author(s):  
P. J. Vickery ◽  
M. J. Hill ◽  
G. E. Donald
Keyword(s):  
Near Infrared ◽  
Perennial Grass ◽  
Vegetation Indices ◽  
Fast Growth ◽  
Perennial Grasses ◽  
Bayesian Probability ◽  
Cumulative Probability ◽  
Botanical Composition ◽  
South Wales ◽  
Native Pastures

Summary. Spectral data from the green, red and near-infrared bands of Landsat MSS and Landsat TM satellite imagery acquired in mid-spring were classified into 3 and 6 pasture growth classes respectively. The classifications were compared with a site database of botanical composition for the Northern Tablelands of New South Wales to examine the association between spectral growth class and pasture composition. Pastures ranged in composition from unimproved native perennial grasses through semi-improved mixtures of native and naturalised grasses and legumes to highly improved temperate perennial grasses and legumes. For 3 years of MSS data, the fast growth class had a mean botanical composition of about 80% improved perennial grass and 0% native; medium growth class averaged 46% improved perennial grass and 14% native; while the slow growth class had about 60% native and 1% improved perennial grass when averaged over 3 years of MSS data. For the 6 class TM data from a single year, a predictive logistic regression of cumulative probability was developed for percentage of ‘very fast’ growth pixels and ordered 10 percentile categories of improved perennial grass or native grass. Differences in patch characteristics between classes with MSS disappeared with TM reclassified to the same 3 class level. Most probable pasture type was inferred from 3 class MSS and TM data using Bayesian probability analysis. The resulting maps were similar in general appearance but detail was better with the TM data. The pasture growth classification identified highly improved perennial grass pastures and native pastures but sensitivity to intermediate pasture types was poor. Future improvement will come from direct measurement of biophysical characteristics using vegetation indices or inversion of reflectance models.

Sources of valuable traits for perennial grass breeding

2021 ◽  
pp. 78-89
Author(s):  
LZ Baistruk-Hlodan ◽  
MM Кhomiak ◽  
HZ Zhapaleu
Keyword(s):  
Festuca Arundinacea ◽  
Trifolium Pratense ◽  
Perennial Grass ◽  
High Energy ◽  
Phleum Pratense ◽  
Perennial Grasses ◽  
Starting Material ◽  
Forage Production ◽  
Daily Growth ◽  
Galega Orientalis

Aim. The purpose was to identify collection accessions – sources of valuable traits to use as starting material for creating varieties of perennial grasses in Western Ukraine. Results and Discussion. Perennial grasses play an essential role in improving the efficiency of forage production. They produce a fodder mass that contains major macro- and micronutrients, minerals, vitamins, amino acids, and other nutrients in available forms, with a high energy protein saturation. Practice shows that due to the introduction of varietal crops into production in combination with optimal technologies of their cultivation, which allows revealing the potential of each variety, it is possible to additionally obtain 20-30% higher yields of fodder mass annually and harvest 2 to 3-fold seed yields. In 2016-2020, a search was carried out and 570 new accessions of perennial grasses were recruited, of which 201 were legumes and 369 were graminaceous grasses. The collection contains 1,319 accessions, of which 232 are Trifolium pratense L., 115 are Trifolium repens L., 49 are Trifolium hybridum L., 107 are Lotus corniculatus L., 80 belong to other legume species (Medicago, Galega orientalis L. Galega orientalis L. and Trifolium species), 131 are Phleum pratense L., 187 are Dactylis glomerata L., 146 are Lolium perenne L., 53 are Arrhenatherum elatius (L.) J. et C.Presl., 67 are Festuca rubra L., 28 are Festuca trachyphylla L., 32 are Bromopsis inermis (Leyss.) Holub, 92 belong to other species of other types of graminaceous grasses (Festuca pratensis Huds., Festuca arundinacea Schreb., Agrostis alba L. etc.). Accessions that enter the Department are registered and sown for propagation in the field. After examination, valuable accessions are transferred to the National Depository and registered in the National Catalogue; the rest of the obtained seeds are used in working collections. Conclusions. The best collection accessions were identified by a set of economically valuable traits: sources of daily growth of shoots (30), winter hardiness (28), plant height (22), yield of green mass upon haymaking (28) and pasture (19) use, forage productivity (15), seed productivity (25), foliage (21), and disease resistance (23). They can be recommended as starting material to create varieties of perennial grasses with high yields of forage mass and seeds for various applications.

scholarly journals Integrated Management of Perennial Pepperweed (Lepidium latifolium)

2008 ◽  
Vol 1 (1) ◽  
pp. 17-25 ◽  
Author(s):  
Rob G. Wilson ◽  
Debra Boelk ◽  
Guy B. Kyser ◽  
Joseph M. DiTomaso
Keyword(s):  
Integrated Management ◽  
Perennial Grass ◽  
Management Strategies ◽  
Site Preparation ◽  
Perennial Grasses ◽  
Flower Bud ◽  
No Till ◽  
Wide Range ◽  
Grass Establishment ◽  
Native Perennial Grass

AbstractPerennial pepperweed is invasive throughout California. It thrives in a wide range of environments and is a common weed in floodplains, pastures, wetlands, and roadsides. In disturbed areas, perennial pepperweed rapidly forms monotypic stands with a thick litter layer. These infestations not only out-compete other vegetation, but prevent re-establishment of desirable species even after perennial pepperweed control. This experiment examined integrated management strategies with the goal of maximizing perennial pepperweed control and establishment of desirable native vegetation. The experiment was conducted at two sites in Lassen County, CA. Both sites were heavily infested with perennial pepperweed and lacked competing vegetation. The experimental design was a split-split-randomized block with four replications. Site preparation treatments included winter burning, summer and fall mowing, winter grazing, and fall disking. These treatments were designed to remove thatch to facilitate herbicide application and reseeding of desirable perennial grasses. Herbicide treatments included chlorsulfuron, 2,4-D, or glyphosate applied at the flower bud stage. Revegetation treatments included no seeding and no-till seeding of native perennial grasses. Most site preparation plus herbicide combinations reduced perennial pepperweed cover > 85% compared to the untreated control, although treatment efficacy was variable between sites and years. Burning, grazing, mowing, or disking in combination with herbicide treatment and no-till seeding was necessary for successful native perennial grass establishment. Burning or mowing with yearly 2,4-D applications for 3 yr gave the best combination of perennial pepperweed control and native grass establishment. Chlorsulfuron caused chlorosis and stunting to western wheatgrass, basin wildrye, and beardless wildrye at both sites when applied the spring before seeding. No treatment offered complete weed control, suggesting follow-up spot herbicide applications are needed for long-term perennial pepperweed suppression. These results provide several successful integrated strategies for control of perennial pepperweed and revegetation to a desired native perennial grass community.

Survey of the productivity, composition and estimated inputs of fixed nitrogen by pastures in central-western New South Wales

2004 ◽  
Vol 44 (12) ◽  
pp. 1165 ◽  
Author(s):  
A. M. Bowman ◽  
W. Smith ◽  
M. B. Peoples ◽  
J. Brockwell
Keyword(s):  
White Clover ◽  
N2 Fixation ◽  
Dry Matter ◽  
New South ◽  
Perennial Grass ◽  
New South Wales ◽  
Subterranean Clover ◽  
Legume Species ◽  
Forage Production ◽  
South Wales

Total productivity and legume nitrogen fixation (N2 fixation) in dryland pastures were examined in a 2 year study (1999–2001) on 118 farms in central-western New South Wales. Pasture exclosure cages, placed at 217 on-farm sites, were harvested on 7 occasions and the foliage hand-sorted according to species in order to measure shoot dry matter (DM). The separated legume shoot material collected in spring 1999 (52 different legume samples) and 2000 (76 different legume samples) from a subset of representative pastures (41 cages on 28 different farms in 1999, 32 cages on 25 different farms in 2000) was also analysed for concentration of nitrogen (%N) and 15N natural abundance. These data were subsequently used to calculate the proportion of the legume shoot N derived from atmospheric N (%Ndfa), comparative measures of the relative efficiency of N2 fixation (kg N fixed/t DM accumulated) and the amounts of shoot N fixed (kg N/ha). The survey encompassed 8 common pasture types, and 5 others that were less common, ranging from native perennial grass pastures with little legume content to lucerne (Medicago sativa L.) pastures with and without companion clovers. Fifteen legume species were found in the pastures, some only occasionally. Lucerne and white clover (Trifolium repens L.) were the only perennials. Mean spring estimates of %Ndfa were similar in 1999 and 2000 for lucerne (72 and 81%, respectively), rose clover (T. hirtum All., 82 and 77%) and annual medics (Medicago spp., 89 and 86%). For the remaining 12 legume species, measures of %Ndfa ranged from 64 to 95% and averaged 83%. Shoot %N contents were greater for lucerne than for the other 14 legumes and this was reflected in the comparative measures of N2 fixation which ranged from 14.5 kg N/t DM for rose clover to 25.7 kg N/t DM for lucerne in 2000. The most productive pasture type comprised lucerne plus balansa clover [T. michelianum Savi var. balansae (Boiss.) Azn.], white clover or arrowleaf clover (T. vesiculosum Savi), but all pasture types that contained lucerne were highly productive. Spring was the most productive season and summer the least. Lucerne was overwhelmingly the most productive legume and was responsible for >83% of the fixed N in those pastures that contained both lucerne and other legumes. Lucerne productivity was approximately uniform throughout the year whereas, for other pastures, especially those based on rose clover or subterranean clover (T. subterraneum L.), there were sharp peaks in spring and little or no dry matter production over summer. The presence of lucerne in pastures significantly (P<0.05) reduced broadleaf weeds. It was concluded that, where there are requirements in central-western New South Wales agriculture for uniform forage production throughout the year and a high input of fixed N, lucerne is substantially superior to other species.

The response to moisture and defoliation stresses, and traits for resilience of perennial grasses on the Northern Tablelands of New South Wales, Australia

2003 ◽  
Vol 54 (9) ◽  
pp. 903 ◽  
Author(s):  
S. P. Boschma ◽  
M. J. Hill ◽  
J. M. Scott ◽  
G. G. Rapp
Keyword(s):  
Festuca Arundinacea ◽  
Plant Biomass ◽  
Nitrogen Concentration ◽  
Perennial Grass ◽  
Basal Area ◽  
Perennial Grasses ◽  
Rooting Depth ◽  
Grass Species ◽  
Severe Drought ◽  
Moderate Drought

A field experiment was conducted to study the effects of defoliation and moisture stresses on perennial pasture grasses and to identify traits associated with their resilience. The experiment, conducted near Armidale on the Northern Tablelands of NSW, studied 4 introduced perennial grass species (Phalaris aquatica, Festuca arundinacea, Dactylis glomerata, and Lolium perenne) and 2 native grass species (Microlaena stipoides and Austrodanthonia richardsonii) subjected to 3 moisture regimes (non-stress moisture, moderate drought, and severe drought) and 2 defoliation intensities (severe and moderate). Basal area, herbage mass, phenological growth stage, nitrogen concentration, root mass, and rooting depth were compared over 2 independent 6-month periods: spring–summer (1 September 1994–28 February 1995) and summer–autumn (1 December 1994–31 May 1995). Multiple regression was used to determine which traits were important for determining plant resilience.The differences between species and their respective responses were evident in the traits measured. In general, basal area tended to increase over summer and show little change during autumn. Severe defoliation stimulated plant growth, resulting in higher harvested herbage mass than from those moderately defoliated. Reproductive development was suppressed by severe drought and reduced by moderate drought. Severe defoliation suppressed flowering of Dactylis and Lolium at both drought intensities, compared with moderate defoliation. Phalaris, Festuca, and Austrodanthonia were the deepest rooting species during spring–summer, and Dactylis the shallowest. All species had similar rooting depths during summer–autumn, with those under severe and moderate drought having the deepest and shallowest rooting, respectively.Carbohydrate reserves and basal area were important traits for determining plant resilience during spring–summer. During summer–autumn, maintaining basal area and plant biomass through moderate grazing was important for resilience.

Effect of sod-seeding oats or barley, renovation, herbicide and broadcast nitrogen fertilizer on forage production of dryland lucerne

1976 ◽  
Vol 16 (79) ◽  
pp. 240
Author(s):  
RA Spurway ◽  
AC Gleeson
Keyword(s):  
Avena Sativa ◽  
New South ◽  
Basal Area ◽  
Early Summer ◽  
N Fertilizer ◽  
Total Production ◽  
Forage Production ◽  
South Wales ◽  
Cereal Species ◽  
Forage Yields

In four experiments at Tamworth, New South Wales in 1973 and 1974, forage production from dryland lucerne pastures (Medicago sativa cv. Hunter River) was evaluated following sod-seeding with oats (Avena sativa cv. Cooba and Coolabah) or barley (Hordeum vulgare cv. Beecher) in autumn, treatment with diquat and topdressing with 50 or 100 kg nitrogen (N) ha-1. Comparisons were also made with production from lucerne alone and with crops of oats and barley sown on conventional seedbeds. Total forage production from lucerne was approximately doubled (P < 0.05) in winter by sod-seeding with oats or barley. Differences between the cereal species were small and both responded significantly to N fertilizer. Herbicide did not significantly affect forage production. The sod-sown cereal reduced (P < 0.05) lucerne growth in winter, but in early summer when cereal growth had ceased neither the growth of lucerne nor its basal area differed significantly from that of unseeded lucerne pastures. In most experiments renovation or broadcasting N fertilizer gave small, but significant increases in lucerne production. Forage yields from conventionally sown oats and barley were 2 to 3 times larger (P < 0.05) than the total production of sod-sown plots. Per cent N in sod-sown oats or barley was almost always less (P < 0.05) than in conventional sowings. Per cent N in both cereals declined significantly between winter and spring

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