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A Review And Commentary On The Bird Life Of Texas By Harry C Oberholser, Gordon Gunter

Mississippi Kite

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Observations On The Nesting Ecology Of Barn Swallows, W. C. Holmes

Mississippi Kite

No abstract provided.

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Front Matter, Mississippi Kite

Mississippi Kite

No abstract provided.

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Jackson Audubon Chapter Meeting, Mississippi Kite

Mississippi Kite

No abstract provided.

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June Breeding Bird Survey - 1971, Mississippi Kite

Mississippi Kite

No abstract provided.

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The Breeding Biology And Distribution Of Swainson's Warbler In Mississippi, W. H. Turcotte

Mississippi Kite

No abstract provided.

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Birding In The Rio Grande Valley, B. Quentin, Frances L. Dowdy

Mississippi Kite

No abstract provided.

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Monthly Changes In Plant Biomass, Net Primary Productivity And Transfer Dynamics Of A Tropical Grazing Land Ecosystem In Southern India, K.S T.K Karuniachamy, K Paliwal

IGC Proceedings (1977-2023)

Monthly changes in plant biomass, net primary productivity and transfer dynamics of tropical grazing land of western Ghats region, southern India, are presented. The annual above- ground net production was 9.03 g/m2/day and the below-ground net production was 2.56 g/m2/day. Total annual net primary production was estimated at 4232 g/m2/day. Of the total input of 11.59 g/m2/day into the system, about 77.9% was channelled to above-ground and 22.1% to belowground, The rate of litter disappearance was 0.55 g/m2/day and l.14 g/ m2/day for below-ground disappearance. The total output was 1.69 g/ m2/day which was 14.6% of the total input. Thus, …

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Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario

IGC Proceedings (1977-2023)

Net CO2 assimilation and plant water relations of the African savanna grasses Panicum maximum Jacq. and Tliemeda triandra Porrsk. were measured under controlled conditions. We hypothesised that 1; triandra would be better adapted to higher light and temperature conditions and could withstand greater moisture stress than could P. maximum, as T. tria11dra is commonly found in open areas, whereas P. maximum dominates in the shade of trees. Plants of both species were transplanted into a common soil in large pots and placed under shade (approximately 150 µrnoVm1/s photon flux density (PFD)) or high light (approximately 1200 µmoVm1/s PFD) conditions, with …

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Grazing Management Effects On Diverse White Clover Cultivars, G E. Brink, G A. Pederson

IGC Proceedings (1977-2023)

Tall fescue (Festuca arundinacea Schreb.) was oversewn with Grasslands Huia, Louisiana S-1, and Regal white clover (Trifolimn repens L.) and stocked the following year continuously or rotationally with cattle to detennine cultivar response to grazing method. When precipitation was 59% above normal, mean leaf area, forage and stolon dry weight, and stolon growing point density in June and August were unaffected by grazing method. These parameters were reduced under continuous stocking when precipitation was 32% below normal. Cultivar ranking for mean leaf area and petiole length was the same as that for leaf size: Grasslands Huin

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Determination Of Nitrogen Sources (Mineral, Atmospheric Or Endogenous) Used By Lucerne During Regrowth, K Tae Hwan, A Ourry, G Lemaire, J Boucaud

IGC Proceedings (1977-2023)

Although for forage legumes such as Medicago saliva, ii is established that nitrogenase activity is very low during the 2 fust weeks of regrowth, there are no data on the amount d nitrogen in regrowin g shoots derived from N1 fixation. In order to ascertain the orisin of N used for regrowth of lucerne, several experiments were unde,taken usin g 15N labellin g to distinguish between endogenous, mineral and atmospheric N recovered' in regrowing shoots of nodulated or non-nodulated lucerne. Calculation of N fluxes from ISN data showed that both N uptake from the medium and N2 fixation strongly decreased …

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Effect Of A Legume (Arachis Pintoi) On The Regrowth And Mineral Nutrition Of Associated Pangola Grass (Digitaria Decumbens), P Cruz, H Sinoquet, O Sobesky

IGC Proceedings (1977-2023)

The effect of a companion legume (Arachis pintoi) on the growth and nitrogen nutrition of an associated grass (Di'gitaria decumbems) was studied during 2 regrowth periods. Digitaria growth was expressed as a function of the cumulative absorded PAR (photosynthetically active radiation) i.e., by using the radiation-use efficiency concept. For this purpose, PAR intercepted by both the pure and mixed swards was estimated by using a radiative transfer model. Nitrogen nutrition status of Digitaria was characterised by the relation between N uptake and dry matter production. Results show a close agreement between N nutrition level and radiation-use efficiency of the grass. …

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Varietal Differences In Brassica Fodder As Affected By Nitrogen Topdressing And Seeding Date, S H. Moon, H Hirota

IGC Proceedings (1977-2023)

Two experiments were carried out both in spring and fall with cultivars of rape (Brassica napus spp.) and C.O. (B. campestris x B. oleracea). Both cullivars showed lillle increase in plant length in spring sowing with nitrogen topdressing, but the increments were higher in earlier topdressing (T l) and later topdressing (T2) than in control in autumn sowing, although the difference was not significant. There was no difference in the number of leaves throughout the growing stages between the N topdressing treatments in spring and autumn sowing. Leaf area was greater in Tl and T2 than in control in early …

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Reserve Mobilization During Regrowth After Cutting Of Forage Species: Quantification And Physiological Mechanisms In Ryegrass And Lucerne, A Ourry, J Bigot, T Kim, J Boucaud, J Salette

IGC Proceedings (1977-2023)

Time course of remobilisation of reserves was studied during the regrowth of Loli11m perem1e and Medicago sativa by 15N labelling, carbohydrate analyses and by measuring time course of several enzymes activities. When photosynthesis decreased during early regrowth, and consequently reduced availability of carbon skeletons within the plant, both nitrogen (N) uptake (lolium perene) and N2 fixatlon (Medicago saliva) decreased. Nilrogenase, as well as nitrate reductase activities, decreased. Reduction of external N assimilation was compensated for by intensive mobilization of endogenous N in roots of lucerne and in stubble of ryegrass. In the same manner, some of …

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Effect Of Temperature On Nitrogen Fixation Rates In Seven Clover Cultivars, J R. Crush, B D. Campbell, J R. Caradus

IGC Proceedings (1977-2023)

Seven white clover (Trifolium repens L) cultivars were grown in growth rooms at S different temperatures between S and 2S°C. Plant growth and nitrogenase activity (acetylene reduction) were measured. There were significant effects of temperature on total plant ay matter (DM) accumulation and nitrogenase activity. Temperature x cultivar interactions were significant for DM accumulation, nitrogenase activity per pot and nitrogenase activity/g DM. There was a strong correlation between DM increment/°C rise in temperature over the range 10-20°C, and nitrogenase activity/g DM. Three cultivars had maximum nitrogenase activity/g plant DM at 200C and 4 cultivars peaked at 15° C. These differences …

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Physiological Characteristics Of Nitrate Uptake By Different Catch Crop Species, P Laine, A Ourry, J Boucaud, J Salette

IGC Proceedings (1977-2023)

The pollution of aquifers by nitrate is aggravated by farming practices that leave the ground bare during winter. Establishment of catch crops during this time could be suitable farming strategy to decrease nitrate loss from the soil. Only a few studies are available on the physiology of nitrate uptake by these species. Experiments were conducted on Lolium perenne, Secale cereale, Trifolium incarnatum, Trifolirim alexendrnum, Phacelia tanacetifolia, Brassica rapa, Brassica napus, Sinapsis alba and Raphanus sativus grown in hydroponic conditions, in order to investigate the physiological basis of the NO3- uptake system when plants are grown with optimum ocniditons of light, …

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Relationships Between Growth And Carbon Isotope Discrimination For Some Pasture Species, J Virgona

IGC Proceedings (1977-2023)

Carbon isotope discrimination (A) by plants can be directly related to plant water-use efficiency (W, total plant dry matter, OM, per water transpired) and used in selection to achieve greater W. As \V (and A) is a complex characteristic, there maybe inherent relationships between it and plant productivity. A range of pasture cultivars (of temperate grasses and legumes) were grown in pots (lo c. 50 days) and \V, A and total dry mailer measured. Among cultivars the relationship between W and A was negative and significant as was the relationship between A and total OM accumulation. A further experiment showed …

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Acquisition And Allocation Of Phosphorus In A Population Of White Clover Plants In A Rotationally Grazed Pasture, M.J M. Hay, D F. Chapman

IGC Proceedings (1977-2023)

This paper quantifies the processes of acquisition, allocation and retranslocation of phosphorus (P) within a white clover (Trifolium repens L.) population in a mixed grass-clover pasture during a regrowth period in early winter (13 May-8 July 1991). The work described is part of a broader study examining seasonal variation in these processes. The data allows an analysis of the changing P economy of plants and of whole populations. White clover plants were grouped by !heir hierarchy of branching. Within plants, stolons were grouped by order of branching, dissected into leaf, stolon and root, oven-dried, weighed and analysed for P …

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Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

This study was undertaken to examine the relative severity of defoliation of young branches (those comprising <4 nodes) and parent stolons of white clover (Trifolium repens L.) in rotationally grazed pastures stocked al either 2.5, 5.0 or 7.5 bulls/ha. On 7 occasions over a year, the defoliation of expanded leaves of parenl and branch stolons was assessed using tagged stolons. Petiole length of leaves ,vas measured before grazing. Leaves of young branch stolons (43% of the total number of leaves defoliated) were less severely defoliated than leaves of parent stolons (64%). Defoliation of branch stolon leaves was relatively greater at the higher stocking rates which had lower residual …

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Effects Of Temperature, Nitrgoen Fertilizer, And Cutting Height On Regrowth And Dry Matter Production, Hyo Won Lee, Mu Hwan Jo, Chang Ho Kim

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata L.) is used extentively in South Korea for green-chop and pasture mixtures. Maintaining orchardgrass stands over summer is a major problem in South Korea. Orchardgrass was grown in soil in growth chambers to evaluate the effect of temperature (day/night:20/JO, 27/17 and 3S/25°C), nitrogen (N) application (0, 5 and 10 kg/ha) and cutting height (5 and IO cm) on plant height, aboveand below-ground dry matter yield, and leaf area accumulation. High temperatures (35/25°C) greatly reduced plant height, DM yields and leaf area expansion, Cutting to 10 cm gave greater DM yields and leaf areas, compared to cutting to …

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Lucerne Dry Matter Accumulation Rate In Yield Differences, D W. Evans, R N. Peaden, W P. Ford

IGC Proceedings (1977-2023)

Lucerne (Medicago sativa L.) improvement historically has been directed at pest resistance, adaptation to climatic conditions and yield. Successful methods of detecting and increasing natural resistance to a range of insect and disease pests have been developed. Knowledge of what plant factors can be successfully manipulated to increase yield per se is less advanced. This research compared several lucernes differing in type and in date of release to determine if different rates of closed-canopy, forage dry matter accumulation have been a factor in yield increases, particularly between older and more recent material. Ten entries ranging in release date from …

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Improving Germination And Seedling Establishment Of Chicory, S N. Hur, W F. Hunt

IGC Proceedings (1977-2023)

Chicory (Cichorium intybus L.) seeds were treated before sowing with polyethylene glycol (PEG 6000) under different PEG concentrations, treatment period and temperatures, and tested for uniformity of germination, establishment and drought tolerance. Suitable seed coating materials were found that improved emergence, establishment and seedling growth when surface sown on established swards. The best primed or coated seeds in germination tests were surface sown in growth cabinet and field.Osmotic priming with PEG accelerated germination of chicory and significantly reduced time taken for germination compared with coated seeds in Petri-dishes, but not in the field. In contrast, coated seeds germinated more slowly …

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Growth Of Temperate Perennial Legumes Over Three Cycles Of Defoliation At Different Temperatures, M A.P Duarsa, M J. Hill, J V. Lovett

IGC Proceedings (1977-2023)

Summer-active legumes such as big trefoil (Lollis ped11nc11lat11s), birdsfool trefoil (Lot11s comic11la111s), crownvelch (Coronilla varia) and cicer milkvetch (Astraga/11s cicer) are needed for summer rainfall areas of the perennial pasture zone in eastern Australia where soil conditions and grazing management do not suit lucerne (Medicago sativa). The growth of these species was compared at 4 temperatures regimens (14/10, 18/14, 22/18, 26/22°C, 12:12 h) for 3 cycles of regrowth where soil moisture was serially changed from field capacity (FC) to 50% PC and back to PC in a growth cabinet pot experiment. Growth rates in lucerne always exceeded those of the …

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Nutrient Cycling In Semi-Arid Grasslands And Savannas: Its Influence On Pattern, Productivity And Stability, Robert J. Scholes

IGC Proceedings (1977-2023)

The grazing animal carrying capacity of tropical semi-arid rangelands is largely controlled by rainfall, but above about 500 mm per annum, soil nutrient status has an overriding role. On low-nutrient soils, which cover vast areas of the ancient land surfaces of Africa, South America and Australia, it is the amount of grass eaten and digested that controls animal production, not the amount produced. On nutrientpoor soils (particularly those deficient in nitrogen and phosphorus) the primary production continues to increase with increasing rainfall, but the acceptability of the forage to ruminants declines, On the nutrient-rich soils of younger land surfaces, both …

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Soil Characteristics And Processes Critical To The Sustainable Use Of Grasslands In Arid, Semi-Arid, And Seasonally Dry Environments, John Williams, Keith R. Helyar, Richard S.B Greene, Rosemary A. Hook

IGC Proceedings (1977-2023)

The focus of this paper is a framework for determining the soil and land properties and processes which are critical to managing grasslands in an ecologically sustainable manner. Essential to the discussion is the development of concepts which allow description of the stability, resilience and sustainability of the agroecosystem as a whole as well as the land resource base. The regions of Australia with arid, semi-arid and seasonally dry environments are defined and related to the dry environments of the world. This provides a background for a brief consideration of major vegetation types and soils within the dry environments of …

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Soil Animal Composition And Distribution In The Leymus Chinensis Grassland Region In Central Part Of North-East Of China, Yin Xiuqin, Li Jiandong, Zhu Tingcheng

IGC Proceedings (1977-2023)

Since 1990, we have investigated the soil animal composition and distribution in the Leymus chinensis (Aneuro chinensis) grassland region in central part of north-east of Chinn. Soil animals were studied in 20 plant communities in 4 habitats. A total of 15 797 soil animals belonging to 4 phyla, 6 classes, 28 orders and 86 families were obtained. Among them, 26 families and 22 species were new records in norlh-easl of China. The dominant groups were Formicidne, Actinedida, Oribatidn, lsotomidne, Rhnbditidae, Dorylainidae. Sparse woods of Ulmus, and the most animal groups (40) and Puccinellia chinapoesis and Heleochalis intersiIa …

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Breeding Phalaris For Tolerance To A Range Of Acid Soils, R N. Oram, A M. Ridley, J Hunter, H E. Schroeder, J Taylor

IGC Proceedings (1977-2023)

Phalaris (Phalaris aquatica L.) is a persistent, drought-hardy grass adapted lo mediterranean climates, but it is sensitive to free aluminum in acid soils. P. arundinacea L is more tolerant of soil acidity, and therefore it has been crossed to P. aquatica, followed by 1 or 2 backcrosses to P. aquatica. Open-pollinated progenies generated by I or 2 generations of random mating without selection were tested at 3 acid soil sites in Victoria and ACT. The mean herbage yields in winter were lower than the phalaris controls, but heritability and expected selection responses were high. There are good prospects …

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Intraspecific Variation For Salt Tolerance In White Clover, M E. Rodgers, C L. Noble, M E. Nicolas, G M. Halloran

IGC Proceedings (1977-2023)

Variation in the salt tolerance of 10 commercial cultivars of white clover (Trifolium repens L.) was evaluated in greenhouse and field· experiments over a range of NaCl concentrations. Cultivars differed significantly in terms of yield, shoot ion concentrations and parameters of growth such as leaf expansion and petiole elongation rates but not in the root concentrations of Cl or Na. The ability to control the entry and distribution of Cl and Na into the shoot (demonstrated by tolerant cultivars Haifa and irrigation compared with sensitive cultivars Ladino and Tamar) was related to the salt tolerance rankings observed in both …

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Breeding For Tolerance To Toxic Levels Of Aluminum In Alfalfa, T A. Campbell, Z L. Xia, P R. Jackson, C D. Foy, G R. Bauchan

IGC Proceedings (1977-2023)

An estimated 40% of all arable soils are acidic, and aluminum (Al) toxicity is often the primary plant-growth-limiting factor in these soils. Bxcess exchangeable Al is especially harmful in subsoils because it reduces rooting depth and branching and predisposes plants,to injury by drought. Our research to date indicates that there is substantial genetic variation in alfalfa (Medicago sativa L.) in response to toxic levels of Al, but that phenotypic recurrent selection appears to have been only marginally effective in selecting for Al tolerance. Possible alternative breeding approaches would entail re-evaluating selections to help obviate the effects of genotype x environment …

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Evaluating Livestock Selling Strategies Based On Forage Availability, Lucas D. Parsch, W M. Watts, O J. Loewer, P L. Luster

IGC Proceedings (1977-2023)

The ORAZB simulation model was used to evaluate 4 alternative decision rules to trigger the removal of stocker steers from pasture in order to avoid risk when pasture conditions are suboptimal, Each of the four decision rules was simulated for 8 stocking rates over a 13- year period, Results of the analysis indicated that decision rules which trigger livestock removal based on minimum herbage availability result in shorter grazing periods and higher average daily gain compared with decision rules which trigger removal based on livestock weight loss. Although decision rules based on minimum herbage availability thresholds resulted in the highest …

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Full-Text Articles in Entire DC Network

A Review And Commentary On The Bird Life Of Texas By Harry C Oberholser, Gordon Gunter

Mississippi Kite

Observations On The Nesting Ecology Of Barn Swallows, W. C. Holmes

Mississippi Kite

Front Matter, Mississippi Kite

Mississippi Kite

Jackson Audubon Chapter Meeting, Mississippi Kite

Mississippi Kite

June Breeding Bird Survey - 1971, Mississippi Kite

Mississippi Kite

The Breeding Biology And Distribution Of Swainson's Warbler In Mississippi, W. H. Turcotte

Mississippi Kite

Birding In The Rio Grande Valley, B. Quentin, Frances L. Dowdy

Mississippi Kite

Monthly Changes In Plant Biomass, Net Primary Productivity And Transfer Dynamics Of A Tropical Grazing Land Ecosystem In Southern India, K.S T.K Karuniachamy, K Paliwal

IGC Proceedings (1977-2023)

Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario

IGC Proceedings (1977-2023)

Grazing Management Effects On Diverse White Clover Cultivars, G E. Brink, G A. Pederson

IGC Proceedings (1977-2023)

Determination Of Nitrogen Sources (Mineral, Atmospheric Or Endogenous) Used By Lucerne During Regrowth, K Tae Hwan, A Ourry, G Lemaire, J Boucaud

IGC Proceedings (1977-2023)

Effect Of A Legume (Arachis Pintoi) On The Regrowth And Mineral Nutrition Of Associated Pangola Grass (Digitaria Decumbens), P Cruz, H Sinoquet, O Sobesky

IGC Proceedings (1977-2023)

Varietal Differences In Brassica Fodder As Affected By Nitrogen Topdressing And Seeding Date, S H. Moon, H Hirota

IGC Proceedings (1977-2023)

Reserve Mobilization During Regrowth After Cutting Of Forage Species: Quantification And Physiological Mechanisms In Ryegrass And Lucerne, A Ourry, J Bigot, T Kim, J Boucaud, J Salette

IGC Proceedings (1977-2023)

Effect Of Temperature On Nitrogen Fixation Rates In Seven Clover Cultivars, J R. Crush, B D. Campbell, J R. Caradus

IGC Proceedings (1977-2023)

Physiological Characteristics Of Nitrate Uptake By Different Catch Crop Species, P Laine, A Ourry, J Boucaud, J Salette

IGC Proceedings (1977-2023)

Relationships Between Growth And Carbon Isotope Discrimination For Some Pasture Species, J Virgona

IGC Proceedings (1977-2023)

Acquisition And Allocation Of Phosphorus In A Population Of White Clover Plants In A Rotationally Grazed Pasture, M.J M. Hay, D F. Chapman

IGC Proceedings (1977-2023)

Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

Effects Of Temperature, Nitrgoen Fertilizer, And Cutting Height On Regrowth And Dry Matter Production, Hyo Won Lee, Mu Hwan Jo, Chang Ho Kim

IGC Proceedings (1977-2023)

Lucerne Dry Matter Accumulation Rate In Yield Differences, D W. Evans, R N. Peaden, W P. Ford

IGC Proceedings (1977-2023)

Improving Germination And Seedling Establishment Of Chicory, S N. Hur, W F. Hunt

IGC Proceedings (1977-2023)

Growth Of Temperate Perennial Legumes Over Three Cycles Of Defoliation At Different Temperatures, M A.P Duarsa, M J. Hill, J V. Lovett

IGC Proceedings (1977-2023)

Nutrient Cycling In Semi-Arid Grasslands And Savannas: Its Influence On Pattern, Productivity And Stability, Robert J. Scholes

IGC Proceedings (1977-2023)

Soil Characteristics And Processes Critical To The Sustainable Use Of Grasslands In Arid, Semi-Arid, And Seasonally Dry Environments, John Williams, Keith R. Helyar, Richard S.B Greene, Rosemary A. Hook

IGC Proceedings (1977-2023)

Soil Animal Composition And Distribution In The Leymus Chinensis Grassland Region In Central Part Of North-East Of China, Yin Xiuqin, Li Jiandong, Zhu Tingcheng

IGC Proceedings (1977-2023)

Breeding Phalaris For Tolerance To A Range Of Acid Soils, R N. Oram, A M. Ridley, J Hunter, H E. Schroeder, J Taylor

IGC Proceedings (1977-2023)

Intraspecific Variation For Salt Tolerance In White Clover, M E. Rodgers, C L. Noble, M E. Nicolas, G M. Halloran

IGC Proceedings (1977-2023)

Breeding For Tolerance To Toxic Levels Of Aluminum In Alfalfa, T A. Campbell, Z L. Xia, P R. Jackson, C D. Foy, G R. Bauchan

IGC Proceedings (1977-2023)

Evaluating Livestock Selling Strategies Based On Forage Availability, Lucas D. Parsch, W M. Watts, O J. Loewer, P L. Luster

IGC Proceedings (1977-2023)