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Sustainability Of A Rocky Grassland Association Over Four Decades, K Torok, G Kosa 2024 Institute of Ecology and Botany of the Hungarian Academy of Sciences

Sustainability Of A Rocky Grassland Association Over Four Decades, K Torok, G Kosa

IGC Proceedings (1977-2023)

The monitoring of vegetation changes Is essential for predicting the direction of future changes. Historic Braun-Blanquet type relev6s of a grassland association were resampled after 4 decades. Ordination techniques were applied to the joint data set. Important displacement of the relev6s was observed in the ordination space, though there is no complete separation of the historic and recent relev6s. No consistent change in species number, no decrease in diversity was experienced, The displacement of relev6s was the consequence of shif'l in the spectrum of life strategies of species: invasion of annuals, The cause of this shif'l may be the increased …


Effect Of Excreta On Stolon Development Of White Clover Under Continuous Cattle Grazing, M I. Rebuffo, R Snaydon, J Morrison 2024 INIA-LA

Effect Of Excreta On Stolon Development Of White Clover Under Continuous Cattle Grazing, M I. Rebuffo, R Snaydon, J Morrison

IGC Proceedings (1977-2023)

The effects of cattle excreta on white clover growth in perennial ryegrass-white clover pastures were studied under continuous grazing. During 2 6-week periods in June-July and September-October. Caltle selectively grazed the sward where urine had been recently voided and subsequently grazed these areas more fequently than other areas, while grazing the sward adjacent to the dung pats less intensively than other areas. Despite differences in of herbage mass and light interception resulting from altered grazing patterns, dung did not affect the density of white clover (Trifolium repens L,) growing points or the number of branches per stolo1i in the …


Allelopathic Effects Of Endophyte In Perennial Ryegrass Residues On Young Subterranean Clover Plants, F J. Snell, P E. Quigley 2024 Department of Food and Agriculture

Allelopathic Effects Of Endophyte In Perennial Ryegrass Residues On Young Subterranean Clover Plants, F J. Snell, P E. Quigley

IGC Proceedings (1977-2023)

Earlier research in Australia and New Zealand has shown that legume growth and persistence may be reduced in the presence of perennial ryegrass (Lolium perenne L.) which frequently contains the endophyte Acreonium lolli Mechanisms to explain these effects need further elucidation. A pot experiment, conducted in a glasshouse, showed that a mulch of senescent perennial ryegrass, which frequently contained A. lolli, reduced the standard of nodulation, root length and shoot and root dry weight of 32-day-old subterranean clover (Trifolium subterranean L.) plants, compared with those grown with mulches which contained less endophyte. The growth of clover plants grown …


Agronomic Behavior Of Binary Mixtures In Basque Country Pastures, M Oyanarte, C Bastida, M Rodriguez 2024 Serviclo de lnvestigacion y Mejora Agraria

Agronomic Behavior Of Binary Mixtures In Basque Country Pastures, M Oyanarte, C Bastida, M Rodriguez

IGC Proceedings (1977-2023)

The present work deals with the total yield and botanical composition of binary mixed pastures resulting from paired combinations of 8 grasses (Italian, perennial and hybrid ryegrass, cocksfoot, tall fescue, timothy, meadow softgrass and prairie grass) and 3 legumes (red clover, white clover and birdsfoot trefoil) with two levels of N, 160 and 320 kg/ha, during a 2-year field trial. In both years prairie grass was the most productive grass in the different combinations and its yield increased considerably with the high rate of N. Cocksfoot and timothy were slow to establish but in the second year they yielded well, …


Establishing Alfalfa Without Tillage, D W. Koch 2024 University of Wyoming

Establishing Alfalfa Without Tillage, D W. Koch

IGC Proceedings (1977-2023)

Establishing alfalfa (Medicago saliva L.) without prior tillage offers advantages over traditional methods in terms of reducing energy and labour requirements, erosion hazard and improving timeliness of operation. An economic advantage to the no-till method has been apparent in recent years. Alfalfa was seeded without prior tillage.after annual crops and into perennial sods. Alfalfa was no-till seeded into perennial sod with less than 10% of the energy and labour required by the conventional tillage method. Alfalfa no-till seeded less than 1 week after sod was treated with glyphosate, was less vigorous and yielded less the seeding year than alfalfa …


Effect Of Manipulative Management Options On A Degraded Pasture Within The Astrebla Spp. Grazing Lands Of Western Queensland, J J. Bushell, J A. Reynolds, D C. Cowan, D G. Phelps, J A. Milson 2024 Queensland Department of Primary Industries

Effect Of Manipulative Management Options On A Degraded Pasture Within The Astrebla Spp. Grazing Lands Of Western Queensland, J J. Bushell, J A. Reynolds, D C. Cowan, D G. Phelps, J A. Milson

IGC Proceedings (1977-2023)

A reduction in Aslrebla spp., and an increase in less palatable and less desirable forbs (Malvastmm americanum Psoralea cinerea), was identified as a problem in some paddocks of the Astrebla grazing lands of central western Queensland's clay soils. To determine possible rehabilitation for these pastures and assist the recovery of Astrebla spp,, a 2-year experiment was conducted near Muttaburra, Queensland (460 mm average annual rainfall), Six main treatments (nil, tine ripping, herbicide, slashing, fire, and a pioneering grass) were combined in a 6x2x2 split piot structure with grazed/not grazed and with additional Astrebla lappacea seed sown/not sown. Interim …


Autumn Management Of Grass-Legume Pasture, D P. Belesky, J M. Fedders, A S. Laidlaw 2024 USDA, Agricultural Research Service

Autumn Management Of Grass-Legume Pasture, D P. Belesky, J M. Fedders, A S. Laidlaw

IGC Proceedings (1977-2023)

Duration of autumn grazing may affect the long-term balance of grass and legume in a sward. Effects of early and late autumn closing dates were studied on productivity and morphology of orchardgrass (Dactylis glomerata) and white clover (Trifolium repens) in replicated grazed swards. Early-closed paddocks continued to accumulate herbage during autumn, resulting in greater winter senescence than late-closed paddocks. Spring-cut herbage mass was not affected by autumn management; however, late closing had significantly more clover than early closing. Early-closed paddocks were grass domlnanl, with few relatively large tillers and few clover growing points compared with late-closed …


Changes In Productivity Associated With Replacement Of Heteropogon Cotortus By Aristida Species And Chrysopogon Fallax In The Savannas Of South East Queensland, F P. Wandera, P C. Kerridge, J A. Taylor, H M. Shelton 2024 University of Queensland

Changes In Productivity Associated With Replacement Of Heteropogon Cotortus By Aristida Species And Chrysopogon Fallax In The Savannas Of South East Queensland, F P. Wandera, P C. Kerridge, J A. Taylor, H M. Shelton

IGC Proceedings (1977-2023)

Heteropogon contortus-dominated rangelands, which cover 22 million ha, are the most important areas for beef production in northern Australia. Due to overgrazing, this dominant species ,is disappearing and is being replaced by unpalatable species such as Aristida and Chrysopogon in a patchy mosaic pattern. In a large graiing experiment· adjacent to the CSIRO Narayen research station: in south-east Queensland on granite country, patches dominated bf the unpalatable grasses comprised 24-32% of the area. Aristida-dominant and Chrysopogon-dominant patches had lower productivity (1000 and 650 kg/ha, respectively) than areas dominated by Heteropogon contorus (1850 kg/ha). It was estimated that a rangeland …


Dynamics Of Stylosanthes Species In Mixed Pastures In A Marginal Environment, J G. McIvor, C J. Gardener 2024 CSIRO

Dynamics Of Stylosanthes Species In Mixed Pastures In A Marginal Environment, J G. Mcivor, C J. Gardener

IGC Proceedings (1977-2023)

The growth and population dynamics of Stylosanthes hamata cv. Verano and S. scabra cv. Seca were measured in mixed, oversown pastures at Hillgrove (AAR=535 mm) near Charters Towers. Over a 10-year period mean stylo yields ranged from 20 kg/ha to 1800 kg/ha. During the first 3 years Verano outyielded Seca but in the last 7 years Seca had greater yields. Plant density was greater for Verano lhan Seca during the early years but the situation was reversed in later years. The Seca plants lived longer than Verano plants and there was a greater proportion of perennial plants in the Seca …


Distribution And Abundance Of Plant Species In Pastures And Rangelands, John G. McIvor 2024 CSIRO

Distribution And Abundance Of Plant Species In Pastures And Rangelands, John G. Mcivor

IGC Proceedings (1977-2023)

The competition-stress-disturbance (CSD) model of Grime (Plant strategies and vegetation processes, New York, John Wiley 1979) is used as the basis for discussing the forces that influence the distribution and abundan.ce. of plant species. Characteristics of plant strategies (competitive, ruderal and stress-tolerator) in both the established and regenerative phases are summarised. Pasture management can be viewed as the manipulation of competition, stress and disturbance. A number of pasture situations ( disturbance-diversity relationships, pasture degradation, weed invasion, management of abandoned farm land, species conservation) are analysed in ecological terms and the consequences for pasture management are outlined. The CSD model can …


Aspects Of Interference Between Nodding Thistle (Carduus Nutans L.) And Pasture Grasses And Legumes, D A. Wardle, K S. Nicholson, A Rahman 2024 AgResearch, NZ

Aspects Of Interference Between Nodding Thistle (Carduus Nutans L.) And Pasture Grasses And Legumes, D A. Wardle, K S. Nicholson, A Rahman

IGC Proceedings (1977-2023)

Nodding thistle (Carduus nutans L.) is an important weed species in New Zealand pastures. The available information on interactions between this species and forage grasses and legumes is summarised and discussed. Nodding thistle inhibits pasture productivity, and allclopathy is probably Important at inhibiting pasture at the later stages of its life cycle. Although, nodding thistle is most susceptible to inhibition by forage species early in its life cycle, a minimum pasture cover may be required for seedlings to establish. Nodding thistle therefore acts as a competitor only at the later stages of its development. Grasses arc both stronger at inhibiting …


Effects Of Herbicides And Fertilizers On Ragwort (Senecio Jacobaea L.) In Hill Country Pastures, A Rahman, K S. NIcholson, D A. Wardle 2024 AgResearch, NZ

Effects Of Herbicides And Fertilizers On Ragwort (Senecio Jacobaea L.) In Hill Country Pastures, A Rahman, K S. Nicholson, D A. Wardle

IGC Proceedings (1977-2023)

A 3-year study was conducted lo determine the influence of 2 herbicides (2,4-D and glyphosate) and 3 fertilisers (containing N, P or K), in conjunctiun with pasture renovation, on ragwort (Senecio jacobaea L.) populations and pasture productivity in a perennial ryegrass-white clover hill country pasture. Glyphosate-treated plots often contained higher ragwort numbers than 2,4-D treated plots, probably because the glyphosate treatment caused greater discontinuity of pasture. Both N and P fertilisers had a consistently strong beneficial effect on pasture, which resulted in substantial inhibition of ragwort populations. During the end of each of the first 2 years of the …


Regeneration Of Themeda Triandra In Humid South African Rangelands, K Adams, J E. Danckwerts 2024 University of Fort Hare

Regeneration Of Themeda Triandra In Humid South African Rangelands, K Adams, J E. Danckwerts

IGC Proceedings (1977-2023)

Themeda triandra seeds were planted into undisturbed, burnt and tilled treatments in degenerate humid grassland. More seedlings emerged and survived on tilled soil than on the other two treatments. The plants on the tilled treatments were also larger (had more tillers with greater mass than the other two). The effect of tillage was attributed to removal of competition from undesirable competitors, which seems essential in the reintroduction of T. triandra into humid grasslands of South Africa.


Effects Of The Fire Regime On Grassland And Savanna Rangelands In Southern Africa, Winston S.W Trollope 2024 University of Fort Hare

Effects Of The Fire Regime On Grassland And Savanna Rangelands In Southern Africa, Winston S.W Trollope

IGC Proceedings (1977-2023)

Fire is regarded as a natural factor of the environment in southern Africa and the effect of fire on rangeland depends upon the fire regime, i.e., type and intensity of fire and season and frequency of burning, The most common types of fire in grassland and savanna areas are surface fires burning either as head or back fires. Head fires have the least depressive effect on the recovery of the grass sward and cause high« topkill of stems and branches of trees and shrubs than back r1res, Fire intensity has no significant effect on the recovery of the grass sward …


Sward Characteristics Of A Diploid And Tetraploid Cultivar Of Perennial Ryegrass As Measured By Different Sampling Techniques, J H. Neuteboom, E A. Lantinga, H Schlepers, L 't Mannetje 2024 Agricultural University

Sward Characteristics Of A Diploid And Tetraploid Cultivar Of Perennial Ryegrass As Measured By Different Sampling Techniques, J H. Neuteboom, E A. Lantinga, H Schlepers, L 'T Mannetje

IGC Proceedings (1977-2023)

In a grazing experiment with monocultures of 2 perennial ryegrass (Lolium perenne L.) cultivars it was found that over a 6-year period the tiller density of the tetraploid Condesa was on average 27% lower than that of the diploid Wendy. The lower tiller density of Condesa went along with a more open sward structure and higher weed proportions after 6 years, Sward structure was suitably characterised by means of absence frequency estimations of rooted perennial ryegrass tillers from concentric sampling quadrats.


Effect Of Localized And Epsidodic Nutrient Supplies And Salinity On Growth Of Selected Grass Species, M M. Wolfson, J Caetano 2024 Roodeplaat Grassland Institute

Effect Of Localized And Epsidodic Nutrient Supplies And Salinity On Growth Of Selected Grass Species, M M. Wolfson, J Caetano

IGC Proceedings (1977-2023)

The efficient use of non•uniform nutrient supplies may be an important component of plant nutrient relationships in soils, especially where inputs of available nutrients by mineralisation may be slow and unpredictable. The experiments reported here examined the effects of periodic supplies of nutrients as well as localised nutrient supplies on the growth of grass species which are common in cultivated soils and pastures. Most plants cannot produce significant yields when grown under saline conditions owing to the difficulty the plant has adjusting to the osmotic potential of the growth medium and its limited capacity to cope with accumulated c1· and …


Analysis Of A Natural Pasture Of The Karst Region (North-East Italy) Under Chemical Fertilization, G Parente, R Ardiani, F Bozzo, M Onofrii, M Scimone, S Venerus 2024 CRSA

Analysis Of A Natural Pasture Of The Karst Region (North-East Italy) Under Chemical Fertilization, G Parente, R Ardiani, F Bozzo, M Onofrii, M Scimone, S Venerus

IGC Proceedings (1977-2023)

To characterise the vegetation changes in a natural pasture, a mineral fertilisation and a 4-year grazing test (1987-1990) were carried out on a typical karstic natural grassland, at that time not grazed by livestock and frequently devastated by fire. Mineral fertiliser and year-long animal grazing have modified the vegetation and seem not to have damaged the agro-ecosystem. An increase of the Arrhenatheretum species and, consequently, higher dry matter production, have been recorded, as well as an extension of the growth period and a greater quantity of grass during the summer. Animal performance has been quite satisfactory as the milk production …


Effect Of Elevation On Vegetation In The Southern Alburz Chain, Iran, Masoud Mohammad-Aliha 2024 Research Institute of Forest and Rangelands

Effect Of Elevation On Vegetation In The Southern Alburz Chain, Iran, Masoud Mohammad-Aliha

IGC Proceedings (1977-2023)

The effects of elevation on the vegetation composition of the southern rangelands (about 20 000 ha) of the Alburz Chain was studied. The attitudinal zones of the study area were located between 1200 and 3600 m asl. Twenty-three sites were selected alongside the attitudinal gradients (every 200 m change in height was allocated a substation). Twenty-one vegetation types were distinguished and 3 ecological sites (stations) selected. Also some grasses alongside the study area have been considered.


Assessing The Productivity Of Pastures In The Central Highlands Region Of Queensland, Australia, J Willcocks, P Filet 2024 Queensland Department of Primary Industries

Assessing The Productivity Of Pastures In The Central Highlands Region Of Queensland, Australia, J Willcocks, P Filet

IGC Proceedings (1977-2023)

A sustainable grazing industry requires careful management of pastures. This study measured the growth potential and productivity of different pasture types in the Central Highlands region of Queensland to develop recommendations on stocking rates which are sustainable in the long term. The most productive pasture measured, buffet grass (Cenchrus clliaris) is generally used for fattening prior to sale to the meatworks. The least productive, a mixed native pasture under a eucalypt forest, is generally used for maintaining breeding stock. Forest Mitchell grass (Bothrioclrloa ewartiana) has intermediate levels of productivity and is used for both breeding and …


Seedling Emergence From Buried Seed In Unsown And Oversown Hill Pasture, M E. Wedderburn, W J. Pengelly, L A. Greaves 2024 AgResearch, NZ

Seedling Emergence From Buried Seed In Unsown And Oversown Hill Pasture, M E. Wedderburn, W J. Pengelly, L A. Greaves

IGC Proceedings (1977-2023)

Seedling recruitment from buried seed was measured in hill country after the resident vegetation was suppressed or killed using herbicide, and either Yatsyn ryegrass, hill ryegrass or a low fertility grass mix was oversown. Unsown plots serves as a control. The total number of seedlings emerging per m2 was similar for all treatments but differences between treatments occurred in the species composition of seedling populations. Ryegrass seedling density in sown plots was 3 times that in unsown plots and white clover seedling numbers were 6 times greater. Other grasses were present in numbers equivalent to sown ryegrass. Subterranean clover and …


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