Forecasting Annual Drought Conditions For Arid And Semi-Arid Rangelands,
2024
USDA, Agricultural Research Service
Forecasting Annual Drought Conditions For Arid And Semi-Arid Rangelands, C L. Hanson, J R. Wight
IGC Proceedings (1977-2023)
Long-term weather forecasts (>14 days) have improved, but still lack accurate enough information to be valuable; thus, drought forecasts must be based on historical records and calculated probabilities of occurrence. The use of regression techniques to investigate linear dependence between current and preceding years' precipitation or forage yield is illustrated. A 3-state Markov process is used to determine relationships between below-average, average and aboveaverage consecutive annual herbage yields, and winter and spring precipitation amounts. Methods for using natl/ml resource simulation models to forecast ecosystem components such as herbage production, runoff, and erosion with their associated probabilities of occurrence are …
Effects Of An Existing Lucerne Sward On Establishment And Productivity Of Three Over Drilled Grass Species,
2024
Lincoln University
Effects Of An Existing Lucerne Sward On Establishment And Productivity Of Three Over Drilled Grass Species, A Z. Ayalsew, B A. Mckenzie, M L. Smetham
IGC Proceedings (1977-2023)
Effects of contrasting lucerne (Medicago saliva L.) cover (open versus closed canopy) on establishment of overdrilled Bromus wifldeowii Kunth cv. Grasslands Matua prairie grass, Pllalari:r aq11a1ica L. cv. Grasslands Matu phalaris and Loli11m pere111Ie L cv. Grasslands Nui perennial ryegrass were investigated. Prairie grass seedling survival was unaffected by lucerne cover at 84%. However, survival of ryegrass and phalaris was reduced to 35 and 46% of their respective values 'under open canopy. Productivity of all 3 species was affected by canopy state. Leaf area per plant, tiller number per plant and dry matter production were all lower under …
Seasonal Water Use And Productivity Of Lucerne-Grass Pastures,
2024
Lincoln University
Seasonal Water Use And Productivity Of Lucerne-Grass Pastures, B A. Mckensize, R J. Lucas, P Gyamtsho
IGC Proceedings (1977-2023)
A. long-term grazing experiment at Lincoln University examined the yield and water use efficiency (WUE) of pure lucerne (Medicago saliva L.), luceme plus Grasslands Matua prairie grass (Bromus wildenowii Kunth.) and lucerne plus Grasslands Maru phalaris (Phalaris aqualica L.). Pure lucerne, lucerne-phalaris and lucerneprairie yielded 12.7, 11.6 and 10.4 t DM/ha/year. Production from deep soils was 16% greater than from shallow soils. Over a 6 month growth cycle from 29 Sept 88 until 16 May 89 total evapotranspiration did not vary between pasture types and mean water use was 378 mm. Water use was 10% higher on …
The Piosphere Effect Of A Goat Corral On The Productivity Of Arid Mediterranean-Type Rangelands In Northern Chile,
2024
Universidad de Chile
The Piosphere Effect Of A Goat Corral On The Productivity Of Arid Mediterranean-Type Rangelands In Northern Chile, S Lailhacar, A Mansilla, L Faundez, P Tonini
IGC Proceedings (1977-2023)
Arid rangelands of northern Chile consist of open shrub formations associated with a seasonal herbaceous stratum. Small pastoralists (comuneros) use the available fodder fer goat raising, by managing individual flocks under continuous grazing. Since each flock spends nights in a corral, a piosphere effect has evolved around it. Through radial transects and quadrals starling from the corral, cover, density, diversity and yield were determined for herbaceous and woody species. Except for shrub diversity and herbage yield, all other total variables showed significant increments with distance. When individual species were considered, different response trends were observed. Some species decreased, others increased, …
Tactical Grazing Can Help Maintain Stability Of Semi-Arid Wooded Grasslands,
2024
CSIRO
Tactical Grazing Can Help Maintain Stability Of Semi-Arid Wooded Grasslands, K C. Hodgkinson
IGC Proceedings (1977-2023)
Arid and semi-arid wooded grasslands in Australia and elsewhere are prone to soil and plant productivity decline when used for pastoral production. Typically, degradation is characterised by woody plant increase, palatable perennial grass decline, unpalatable grass increase and lowered productive capacity of the soil, New grazing management that maintains productivity of plant and soil resources and sustains rehabilitation is required. In a grazing experiment on a mulga (Acacia aneura) woodland, grazing-induced death and impaired seed productivity were observed in palatable perennial grasses. A tactical grazing management to prevent an adverse change in pasture composition and productivity was designed involving progressively …
Temporal Patterns Of Soil Loss In Tropical Grazing Lands,
2024
Queensland Department of Primary Industries
Temporal Patterns Of Soil Loss In Tropical Grazing Lands, D J. Myles, A J. Pressland, J C. Scanlan, P D. Fleming
IGC Proceedings (1977-2023)
Rates of soil erosion in grazing lands of north Queensland were measured at 3 sites over 3 years. Within years, soil loss was highest during summer, even though rainfall was often higher in autumn than in summer. This pattern is explained by lower cover and higher rainfall intensities during summer than autumn. Grazing management should aim at having sufficient cover at the end of the dry season (September-October) to prevent soil loss from high intensity storm rains common at this time of year.
Management Strategies To Improve Indigenous Meat Goat Productivity In Semi-Arid Areas Of Southern Africa,
2024
University of Zimbabwe
Management Strategies To Improve Indigenous Meat Goat Productivity In Semi-Arid Areas Of Southern Africa, L R. Ndlovu
IGC Proceedings (1977-2023)
The semi-arid areas of southern Africa are characterised by low and erratic rainfall coupled with sandy soils which result in severe fluctuations in feed quality and quantity. Goats are an important component of farming systems in these areas but their meat production is constrained by shortage of feed in the dry season. Young goats are particularly vulnerable and management systems that prevent weight loss during the dry season are needed. Positive growth rates in kids· aged 8-60 weeks were obtained in response to feeding 200-400 g of Dolichos lablab (a drought-tolerant fodder) or Acacia lorti/is pods (a naturally occurring feed …
Infiltration Measurements In The Semi-Arid Woodlands Of Eastern Australia- A Comparison Of Methods,
2024
CSIRO
Infiltration Measurements In The Semi-Arid Woodlands Of Eastern Australia- A Comparison Of Methods, R S.B Greene
IGC Proceedings (1977-2023)
The infillracion race of bare, scony, runoff zones of a massive red earth soil in a semi-arid woodland was measured using a disc permeameter (waler supply potential +10 mm), rainfall simulalor and a i arge, bounded, runoff plol, The steady slate infiltration race measured with the disc permeameter was higher than Chai measured wilh the rainfall simulator, Raindrop impact and overland flow effecls wilh the rainfall simulator rearranged parlicles at Che soil surface and resulced in Che formalion or a rain-induced crust. This cruse had a lower infillralion rate than Che surface formed wilh the disc permeameler. The infillrationratcmeasured with …
Plant Demography And Grassland Community Balance: The Contribution Of Population Regulation Mechanisms,
2024
Texas A&M University
Plant Demography And Grassland Community Balance: The Contribution Of Population Regulation Mechanisms, David D. Briske, Jonathan W. Silvertown
IGC Proceedings (1977-2023)
It is widely recognised that many grassland communities are stable,though the mechanisms that maintain this stability are only poorly understood. We identify and discuss processes that contribute to stability at three levels of grassland organisation: 1) the individual plant, 2) the population, and 3) the community. At the level of the individual plant, the classical theory of apical dominance does not consistently explain the response of tiller recruitment to defoliation. At the level of the population, conclusions regarding tiller recruitment in response to radiation quality in the competitive neighbourhood and the contribution of dormant axillary buds to annual tiller recruitment …
Herbage Yields Of Barley And Hungarian Vetch Or Hairy Vetch At Different Seeding Rates,
2024
Field Crops Research Centre, Turkey
Herbage Yields Of Barley And Hungarian Vetch Or Hairy Vetch At Different Seeding Rates, M Munzur
IGC Proceedings (1977-2023)
In a 2-year trial under dryland conditions on fallow land, an experiment was conducted to determine herbage quantity and quality of the mixtures of barley (Hordeum vulgare L.) and Hungarian vetch (Vicia pannonica Crantz.) or hairy vetch (Vicia villosa Roth.) grown at different seeding rates. Barley-vetch seeding rates were %: 100-0, 80-20, 60-40, 40-60, 20-80, 0-100. Seeding rates at 100% were 300 and 200 viable seeds/m2 for barley and vetches, respectively. Mean herbage dry matter (DM) and crude protein (CP) yields were different (P<0.05) among seeding rates with a 2-year average yield of 2058- 4742 kg DM/ha and 233-508 kg CP/ha. Botanical composition of the mixtures, based on weight, was generally 24-48% and 20-43% for Hungarian vetch and hairy vetch respectively, The best seeding rates in terms of herbage yield and crude protein yield were 20-80 or 40- 60, which are those equivalent to 60-160 or 120-120 seeds/m2 for barley and vetches, respectively. Mixtures of barley-vetches gave a better performance than barley or vetches grown alone.
Control Rumex Obtusifolius L. By Manipulating Grass Seeding Rate For Re-Establishment Of Pasture,
2024
Tohoku National Agricultural Experiment Station
Control Rumex Obtusifolius L. By Manipulating Grass Seeding Rate For Re-Establishment Of Pasture, M Nashiki, R Meguro, T Suyama
IGC Proceedings (1977-2023)
For the renovation of deteriorated pastures O\\'ing to the invasion of Rumex obtusifollus L. sprout, manipulation of seeding rate of pasture plants was Investigated to reduce R. obtusifolius. In an autumn-sown sward, Loilum perenne L. was sown at 100, 300, 600, 1000 and 2000 g/a, Dactylis glomerata L. at 600 gta, and a mixture of 6 species were sown together with SO g/a of R, obtusifolius. Plant density and dry weight of R. obtusifolius declined clearly at high rates (1000 and 2000 g/a) of L. perenne compared with low rates, though this difference was likely to disappear …
An Approach For Testing The Ecological Amplitude Of Herbage Cultivars,
2024
AgResearch, NZ
An Approach For Testing The Ecological Amplitude Of Herbage Cultivars, B D. Campbell
IGC Proceedings (1977-2023)
A technique is described for testing the response of cultivars to environmental factors using crossed, controlled gradients of mineral nutrient supply and simulated grazing. The usefulness of the technique was tested by growing the perennial ryegrass (Lolium perenne L.) cultivar Melle and the cocksfoot (Dactylis glomerata L.) cultivar Sylvan in isolation and in a complex mixture on the matrix. Contour maps of the frequency of tillers of the cultivars after 2 years' growth indicated that Melle is better suited to high fertility, heavily stocked sites. The technique may be useful as a compact, standardised method for cultivar testing.
Potential Role Of Some Alternative Perennial Legume Species For Low Fertility, Summer-Dry Hill Country,
2024
AgResearch, NZ
Potential Role Of Some Alternative Perennial Legume Species For Low Fertility, Summer-Dry Hill Country, M B. Dodd
IGC Proceedings (1977-2023)
Limitations to perennial legume persistence and growth in summerdry hill country pastures of New Zealand may be overcome by the development of better-adapted species and cultivars. Ten alternative temperate perennial legume species were grown in a typical hill soil to evaluate herbage growth, morphology and flowering characteristics. Comparison was made with a commonly used standard white clover cultivar. Key species for further development have been identified,
Multi-Species Mixtures As A Pasture Research Technique,
2024
AgResearch, NZ
Multi-Species Mixtures As A Pasture Research Technique, D Scott
IGC Proceedings (1977-2023)
From the hypothesis that each pasture species has a particular management-environmental niche to which it is best suited, it is suggested that an appropriate screening technique is to sow a range of species into the system of interest and let natural selection show species suitability. This is demonstrated in one trial in rangeland and another in developed pastureland.
Elephantgrass Establishment In Morogoro, Tanzania,
2024
University of Wales
Elephantgrass Establishment In Morogoro, Tanzania, E J. Mtemgeti, D Wilman
IGC Proceedings (1977-2023)
In 2 field experiments in Morogoro, Tanzania, 2 methods of establishing elephantgrass (Pennisetum purpureum) were compared: (a) the traditional method in which stem sections were planted with 2 nodes covered with soil and a third node exposed, and (b) horizontal planting of stem sections, buried below 6 cm of soil. The yield of leaf plus "stem" 12 weeks after planting was 35-39% higher with the horizontal method than with the traditional one. The number of tillers produced from the centre node of the 3 planted in each stem section was not much affected by the method of planting, …
Seed Production And Autumn Germination As Determinants Of The Success Of Subterranean Clover In A Cool Temperate Environment,
2024
Lincoln University
Seed Production And Autumn Germination As Determinants Of The Success Of Subterranean Clover In A Cool Temperate Environment, M L. Smetham, S Hines, D W. Jack
IGC Proceedings (1977-2023)
A field experiment examined seed production and autumn germination of subterranean clovers (Trifolium subterraneum L.) In an area of New Zealand with a mean annual rainfall of 62S mm and dry summers. In the fourth autumn, out of 42 accessions, only 10 produced more than the 1000 seedlings/m2 and had seed reserves in excess of the 240 kg/ha considered necessary for success. Of the named cultivars only the early-flowering cv. Geraldton exceeded these thresholds whereas cv. Seaton Park, Woogenellup, Mount Barker and Tallarook did not. All lines had In excess of 50% hard seed 3 weeks after the autumn …
Botanical Composition, Improvement Intervention And Cattle Weight Gain Of Natural Pastures Of Western Ethiopia,
2024
Institute of Agricultural Research
Botanical Composition, Improvement Intervention And Cattle Weight Gain Of Natural Pastures Of Western Ethiopia, L Gizachew, A Tadesse, A Hassen
IGC Proceedings (1977-2023)
The dominant indigenous grass and legume species in the highland (above 2000 m) and mid-altitude (1600-2000 m) parts of western Ethiopia were determined. Grasslands in the high altitude contain a higher proportion of a nutritious grass and legume species than grasslands in the mid altitude. Fertiliser, manuring and legume oversowing improved dry matter yield and live-weight gains of grazing animals. Incorporating forage legumes into natural pastures by oversowing is the best pasture improvement strategy.
Factors Affecting The Distribution Of Microlaena Stipoides On The Northern Tablelands Of New South Wales,
2024
University of New England
Factors Affecting The Distribution Of Microlaena Stipoides On The Northern Tablelands Of New South Wales, D B. Magcale-Macandog, R.D B. Whalley
IGC Proceedings (1977-2023)
The eJClent of and the factors affecting the disllibution of Microlaena sllpoldeJ on the Northern Tablelands of NSW were examined in a SHH:) of 102 paddocks on 33 properties. Relationships between the abundance of M. stilpoides and spatial, climatic and pasture management factors were determined udng 'X} tests. Paddocks with more abundant M. s,ipoides were obse1Yed in the eastern and southern parts of the Tablelands where alcitudc and rainfall are higher. Tree densit) also had a posilive association with its abundance as it grows well under shade. Cultivation and sowing of exotic pasture species initially eliminated 01 reduced the abundance …
Seedling Emergence And Survival Of Medicago Minima And Erodium Cicutarium In Semi-Arid Argentina,
2024
CONACyT
Seedling Emergence And Survival Of Medicago Minima And Erodium Cicutarium In Semi-Arid Argentina, D E. Fresnillo-Fedorenko, O Elia, O A. Fernandez, C A. Busso
IGC Proceedings (1977-2023)
The emergence from naturally deposited seed of Medicago minima (L,) Grufb. var. minima (Mm) and Erodium circutarium (L.) L'Heril. (Ee) seedlings, and subsequent seedling survival, was studied under different levels of herbaceous vegetation cover in the Calden District ( 10 million ha) of semi-arid Argentina. Five cohorts of Mm seedlings and one of Ee were monitored throughout the 1989 growing season. Seedling emergence of Mm in areas with bare soil patches was about twice that in covered areas, while no differences in emergence of Ee between vegetation stales were found. Survival rates of Mm were lower In areas with bare …
Recovery And Germination Of Switchgrass Seed Fed To Cattle,
2024
Texas A&M University
Recovery And Germination Of Switchgrass Seed Fed To Cattle, W R. Ocumpaugh, J W. Stuth, S R. Archer
IGC Proceedings (1977-2023)
Mature rumen-cannulated crossbred steers (Bos spp.) maintained on a bermudagrass (Cynodon dactylon (L.) Pers.) hay diet were rumen ally dosed with switchgrass cv. Alamo (Panicum virgatum L.) seed. Seed we1e recovered from faeces (3 steers in Trial 1 and 7 steers in Trial 2) collected at 12, 24, 48, 72, 96 and 120 h post-feeding, Laboratory germination tests conducted on ·recovered seed indicated that germination decreased by 0,7 to 1.0 percentage unit/hour of rCllident time in the gastrointestinal tract. Variation was observed among steers within and among trials for a number of seed traits measured, but there was …
