Pasture systems to improve productivity of sheep in south-western Victoria. 1. Growth, composition, nutritive value and persistence of resown pastures

2009 ◽  
Vol 49 (8) ◽  
pp. 654 ◽  
Author(s):  
Geoffrey Saul ◽  
Gavin Kearney ◽  
Dion Borg
Keyword(s):  
Nutritive Value ◽  
Subterranean Clover ◽  
Local Environment ◽  
Perennial Grasses ◽  
Stocking Rate ◽  
Pasture Production ◽  
P Rate ◽  
The Difference ◽  
Western Victoria ◽  
Over Time

Two pasture systems were compared at five on-farm sites across south-western Victoria between 1990 and 1996. The ‘typical’ pasture treatment mimicked the pasture and grazing management common in the region, with volunteer annual-based pastures fertilised with around 5 kg/ha phosphorus (P) each year. The ‘upgraded’ pasture treatments were resown to phalaris, perennial ryegrass and subterranean clover, and higher rates of fertiliser (13–25 kg P/ha.year) plus other nutrients were applied. Both pastures were set stocked with the participating farmers breeding ewes. Stocking rate was an emergent variable on each plot. The stocking rate on the typical treatments was based on normal farm practise. Initially, the stocking rate of the upgraded pastures was 15% higher than for the typical pastures and increased over time depending if the ewes in the upgraded pastures were heavier than those in the typical pastures. Measurements included soil fertility, pasture production, nutritive value and composition, and animal production. Net annual pasture production of the upgraded pastures was 10 500 kg/ha compared with 8700 kg/ha for the typical pastures. This average difference (18%) between the treatments was greatly influenced by the large advantage (40%) of the upgraded pasture in the wet year of 1992. Upgraded pastures had higher pasture production than typical pastures in spring but the reverse occurred in autumn. In a separate small plot experiment, the response of each pasture to higher P fertiliser applications was tested. In autumn and winter, there was a significant interaction between pasture type and P rate, with higher responses on the upgraded pastures. In spring, both pastures responded to increased P applications but the upgraded pastures were more responsive at all P rates. The upgraded pastures contained significantly higher legume content (30–50%) than the typical pastures (10–20%). The proportion of sown perennial grasses in the upgraded pasture declined from around 30 to 10% after 6 years displaced by annual grasses and broad-leaf weeds. Herbage from upgraded pastures had significantly higher crude protein content (2–7 units) and digestibility (1–10 units) than the typical pastures with the difference between the treatments increasing over time. The set stocking policy used in this experiment is likely to have exacerbated the decline in sown perennial grasses and implementation of some form of strategic or rotational grazing may have improved persistence. The experiment also highlights the importance of selecting perennial grasses able to cope with the local environment and grazing conditions. Despite the decline in perennials, these results show significant potential to improve pasture productivity and quality in south-western Victoria.

Effects of superphosphate fertiliser and stocking rate on the nutritive value of perennial ryegrass and subterranean clover herbage

1999 ◽  
Vol 50 (4) ◽  
pp. 537 ◽  
Author(s):  
G. R. Saul ◽  
G. A. Kearney ◽  
P. C. Flinn ◽  
C. L. Lescun
Keyword(s):  
Perennial Ryegrass ◽  
Crude Protein ◽  
Dry Matter ◽  
Nutritive Value ◽  
Subterranean Clover ◽  
Stocking Rate ◽  
Western Victoria ◽  
Stocking Rates ◽  
Infertile Soils

The effect of superphosphate fertiliser on digestible dry matter (DDM) and crude protein (CP) percentages of perennial ryegrass and subterranean clover was assessed on a long-term, grazed experiment in western Victoria. CP of both species increased significantly (3–6 units) where long-term average phosphorus (P) applications were 33 kg/ha.year compared with 1 kg/ha.year. CP of herbage was also greater on paddocks grazed at higher (9–23 ewes/ha) than lower (5–13 ewes/ha) stocking rates (1–3 units). DDM of subterranean clover significantly increased (8–10 units) with higher superphosphate applications but there was little effect on the DDM of perennial ryegrass. Long-term applications of superphosphate were associated with larger increases in both DDM and CP than if the same rate was applied in autumn of the year of measurement. For subterranean clover, 30 kg/ha of P applied to infertile soils (Olsen P 5 mg/kg) in autumn increased the DDM of herbage collected in September by only 4–6 units. The nutritive value of most volunteer pasture species also increased with higher superphosphate applications but the DDM of these species was usually inferior to perennial ryegrass. The results highlight the importance of monitoring nutritive value, pasture composition, and herbage production to quantify fully the likely effect of fertiliser applications on animal production.

Effect of two tree windbreaks on adjacent pastures in south-western Victoria, Australia

2002 ◽  
Vol 42 (6) ◽  
pp. 809 ◽  
Author(s):  
P. R. Bird ◽  
T. T. Jackson ◽  
G. A. Kearney ◽  
K. W. Williams
Keyword(s):  
Water Content ◽  
Water Use ◽  
Subterranean Clover ◽  
Temperate Climate ◽  
Pasture Production ◽  
North West ◽  
The North ◽  
Yield Production ◽  
The Difference ◽  
Western Victoria

The effects of 2 tree windbreaks on pasture production in adjoining paddocks were assessed over 4 years in a cool-temperate climate, perennial pasture area in south-western Victoria, Australia. The Willandra windbreak was 2 rows of direct-sown black wattle (Acacia mearnsii) aligned south-east–north-west. The Helm View windbreak was 4 rows of mixed Eucalyptus, Casuarina and Acacia spp., aligned east–west. Pastures at both sites had been sown to perennial ryegrass and subterranean clover. Wind direction data indicated that the north-eastern and south-western paddocks at Willandra were sheltered 39 and 28% of the time, respectively. The northern and southern paddocks at Helm View were sheltered 34 and 42% of the time, respectively. The relationship of rainfall with wind speed and direction was examined to indicate the potential of windbreaks of various orientations to protect livestock. The windbreaks had clear effects on pasture production in the competition zone along the margins of the windbreak. Average pasture production at Willandra in the zone 0.5–0.75 H (where H is the windbreak height) was 69% of open yield; production in the 0.9–1.5 H zone was 96%. At Helm View, production in the zone 0.7–1.0 H was 74% of open yield, with 81% in the zone 1.1–1.5 H. Averaged over all years, both windbreaks had no effect on pasture growth in the 2–10 H sheltered zone, although in some years there were small significant growth increases at parts of that zone in certain paddocks. Periodic soil moisture measurements at Willandra showed that water use was greater in the competition zone near the windbreak, with a difference in summer water content of the 1.2 m profile of at least 20 mm between soil 4.6 m from the windbreak and further away. The difference was due to greater water use from the deepest part of the profile. No other effects of the windbreak on soil water content were observed.

Effect of environmental factors on the growth of grazed pasture in south-western Victoria

2006 ◽  
Vol 46 (4) ◽  
pp. 545 ◽  
Author(s):  
H. A. Birrell ◽  
R. L. Thompson
Keyword(s):  
Climatic Factors ◽  
Subterranean Clover ◽  
Botanical Composition ◽  
Stocking Rate ◽  
Daily Growth ◽  
Pasture Production ◽  
Grazed Pasture ◽  
Herbage Yield ◽  
Western Victoria ◽  
Stocking Rates

This paper presents work from several studies on pasture production that were conducted in south-west Victoria at the Pastoral Research Institute, Hamilton. The frequency with which pasture growth commenced for each week of autumn in the years from 1965 to 1991 was assessed. The median period for the commencement of growth was in the third week of March (although the average date was March 27). Autumn data from several trials conducted over 3 decades were collated and analysed. A relationship between the grazed pasture yield (average of stocking rates plots) at the end of autumn and the rainfall showed that 200 mm of rainfall in the 3 months to the end of May was optimal while higher rainfall depressed the growth. The average daily growth rates of introduced pasture (perennial rye grass, Lolium perenne L. cv. Victorian, phalaris, Phalaris aquatica L. cv. Australian, subterranean clover Trifolium subterranneum L. and volunteer species) were measured in 2- and 4-week growth periods (G 2 and G 4, kg DM/ha.day) for the seasonal growth cycles over 4 years (1980–84 except 1983) when grazed by Merino wether sheep at stocking rates of 10, 13 or 18 sheep/ha. The rainfall throughout the study was lower than normal. Although differences in the animal performance between the stocking rates were only small, at the low stocking rate capeweed (Arctotheca calendula L.) in patches became the major component of the sward. Greater variation in G 2 than in G 4 indicated that growth responded quickly to current environmental conditions. A nonlinear regression accounted for 74% of the variance in G 2 when related to the 3 climatic factors of daylength, soil temperature at 10 cm depth and the soil moisture to a depth of 10 cm, and a plant factor of green herbage yield. The 26 % of unaccounted variance appears to be associated with an effect of stocking rate, possibly botanical composition. The botanical composition was not continuously monitored hence the only sward character included in the investigation was herbage yield. Comparison of the patterns of pasture growth from different latitudes indicated that while the growth pattern in south-western Victoria is erratic, it is intermediary between Mediterranean and temperate pasture types. Understanding this aspect has implications for improving the efficiency of animal production in this environment.

Pasture systems to improve productivity of sheep in south-western Victoria 2. Animal production from ewes and lambs

2011 ◽  
Vol 51 (11) ◽  
pp. 982 ◽  
Author(s):  
Geoffrey Saul ◽  
Gavin Kearney ◽  
Dion Borg
Keyword(s):  
Flow Analysis ◽  
Subterranean Clover ◽  
Supplementary Feeding ◽  
Stocking Rate ◽  
Discounted Cash Flow ◽  
Condition Score ◽  
Western Victoria ◽  
Breakeven Point ◽  
Gross Margins ◽  
On Farm

Two pasture systems (Typical, Upgraded) were compared at five on-farm sites across south-western Victoria between 1990 and 1996. The Typical pasture treatment mimicked the pastures common in the region, with volunteer annual-based species fertilised with ~5 kg/ha.year phosphorus (P). The Upgraded pasture treatment was sown to phalaris, perennial ryegrass and subterranean clover using cultivars recommended for the particular area. Higher rates of fertiliser (13–25 kg/ha.year P) plus other nutrients were applied. Both pastures were set-stocked with breeding ewes. The stocking rate on the Typical treatments was based on normal farm practice. Initially, the stocking rate of the Upgraded pastures was 15% higher than the Typical pastures and increased over time depending if the ewes in the Upgraded pastures were heavier than those in the Typical pastures. Measurements included pasture growth, composition and persistence, ewe stocking rates, ewe and lamb liveweights and condition scores, lambing, marking and weaning percentages, fleece characteristics and supplementary feeding. Over the 6 years, the average carrying capacity of the Upgraded pastures was 18.0 DSE (Dry Sheep Equivalents)/ha compared with 10.2 DSE/ha on the Typical pastures (P < 0.001). As well, the ewes on the Upgraded pastures were 2–3 kg heavier (P < 0.001) and 0.3 condition score higher (P < 0.001) than those on the Typical pastures. Ewes grazing the Upgraded pastures cut significantly more wool per head (4.8 versus 4.5 kg) of higher micron wool (23.1 versus 22.6 um, P < 0.001) but with similar yield and strength. There was no difference in the supplementary feeding required on the treatments. Ewes grazing Upgraded pastures had significantly higher lambing (116 versus 102%), marking (86 versus 81%) and weaning percentages (84 versus 79%) and weaned significantly heavier lambs (23.6 versus 22.6 kg) than those on Typical pastures. There was less feed on offer (P < 0.05) in the Upgraded pastures compared with the Typical pastures in autumn–winter but similar or higher levels in spring and summer. Gross margins using current costs and prices were $20 and $24/DSE for the Typical and Upgraded pastures, respectively. These values were used in a discounted cash flow analysis to determine the long-term benefits of the treatments. Assuming a 12-year life for the pasture, the internal rate of return was 27% with the breakeven point in Year 7. Treatment and ewe condition score significantly influenced lambing percentage with ewes in condition score 3.0 at joining having a lambing percentage of 111% compared with 95% if at condition score 2.3. Irrespective of condition score, ewes grazing Upgraded pastures had a 7% higher lambing percentage than those grazing the Typical pastures. Ewe condition score and lambing time significantly affected weaning weight. Lambs born to ewes in condition score 2.3 during pregnancy and lambing in autumn, reached only 32% of mature ewe liveweight at weaning whereas lambs from ewes at condition score 3.0 achieved 51% of mature weight by weaning.

Steer gains, pasture yield and pasture composition on native pasture and on native pasture oversown with Indian couch (Bothriochloa pertusa) at three stocking rates

1997 ◽  
Vol 37 (7) ◽  
pp. 755 ◽  
Author(s):  
R. J. Jones
Keyword(s):  
Perennial Grasses ◽  
Grass Species ◽  
Stocking Rate ◽  
Pasture Grass ◽  
Pasture Production ◽  
Heteropogon Contortus ◽  
Native Pasture ◽  
Unit Increase ◽  
Stocking Rates ◽  
Pasture Yield

Summary. Pasture production and steer liveweight gain were compared on native pasture (Bothriochloa decipiens, Heteropogon contortus, Themeda triandra and Chrysopogon fallax) and on native pasture oversown with Indian couch or Indian bluegrass (Bothriochloa pertusa). This grass was not a planned introduction to the area but is spreading in Central and North Queensland and its value as a pasture species is questioned by graziers. There were 3 nominal stocking rates of 0.3, 0.6 and 0.9 steers/ha. Each paddock was stocked with 3 steers of stratified ages. The experiment was sown in March 1988 and terminated in June 1993. The experiment, sited 50 km south of Townsville in eucalypt woodland on a solodic-solodised-solonetz soil, was sown in March 1988 and terminated in June 1993. Increases in stocking rate resulted in a linear decline in both pasture yield (by 3–5 t/unit increase in stocking rate) and steer gains (by more than 100 kg/unit increase in stocking rate). Differences between pastures were apparent only at the medium and high stocking rates where, over time, Indian couch gave higher pasture yields and steer gains. Younger steers gained far more weight than older steers. Mean gains over 3 years were weaners 125 kg/year, yearlings 93 kg/year and 2-year-old steers 46 kg/year. Native pasture remained fairly stable botanically at the low stocking rate, but the tufted perennial grass species declined at both the medium and high stocking rates. Sowing Indian couch hastened the botanical changes due to stocking rate, and it became the dominant species at these higher stocking rates. At the low stocking rate, the contribution of Indian couch declined from initial values indicating that this is not an invasive species in the area at a low stocking rate. Contribution of Indian couch to pasture yield was linearly related to stocking rate. Nutritional quality of the Indian couch was similar to the other native perennial grasses though calcium concentration was higher. Increased steer gains were related to higher yield on Indian couch pastures at the higher stocking rates rather than to improved quality. Maximum liveweight gain/ha was achieved at about 0.6 steers/ha. Stocking at 0.9 steers/ha was not sustainable. Even at the low stocking rate, steers would need to spend about 2.8 years on the pastures after weaning to reach 500 kg liveweight. It was concluded that B. pertusa is a useful pasture grass in this environment giving steer gains equal to, or higher than, the gains from the native pasture which it replaced.

Influence of stocking rate and mixed grazing of Angora goats and Merino sheep on animal and pasture production in southern Australia. 1. Botanical composition, sward characteristics and availability of components of annual temperate pastures

2010 ◽  
Vol 50 (2) ◽  
pp. 138 ◽  
Author(s):  
B. A. McGregor
Keyword(s):  
Subterranean Clover ◽  
Botanical Composition ◽  
Stocking Rate ◽  
Bare Ground ◽  
Pasture Production ◽  
Weed Invasion ◽  
Merino Sheep ◽  
Grazed Pastures ◽  
Temperate Pastures ◽  
Angora Goats

The effects of animal species (AS; Angora goats, Merino sheep or goats and sheep mixed grazed together at ratio 1 : 1) and stocking rate (SR; 7.5, 10 and 12.5 animals/ha) on the availability, botanical composition and sward characteristics of annual temperate pastures under continuous grazing were determined in a replicated experiment from 1981 to 1984. AS and SR had significant effects on pasture availability and composition and many AS × SR interactions were detected. The pastures grazed by sheep had significantly reduced content and proportion of subterranean clover and more undesirable grasses compared with those grazed by goats. There were no differences in dry matter availabilities between goat- and sheep-grazed pastures at 7.5/ha, but at 10 and 12.5/ha goat pastures had significantly increased availabilities of green grass, dead and green clover and less weeds compared with sheep pastures. There was a significant AS × SR interaction for the density of seedlings in May following pasture germination. Between July and January, the height of pastures was greater under goats than sheep but from January to March pasture height declined more on goat-grazed than on sheep-grazed pastures. There was an AS × SR interaction for incidence of bare ground. Increasing the SR increased bare ground in pastures grazed by sheep but no change occurred on pastures grazed by goats. Changes in pasture characteristics due to increased SR were minimised on pastures grazed by goats but the grazing of sheep caused larger and faster changes and the pastures were damaged at the highest SR. Goats did not always select the same herbage material as sheep, changed their selection between seasons and were not less selective than sheep. Angora goats were flexible grazers and continually adapted their grazing behaviour to changing herbage conditions. Goat grazing led to an increase in subterranean clover, an accumulation of dead herbage at the base of the sward, reduced bare ground, taller pastures in spring and a more stable botanical composition. Mixed-grazed pasture characteristics were altered with SR. With careful management Angora goats on sheep farms may be used to manipulate pasture composition, to speed up establishment of subterranean clover, to decrease soil erosion and to reduce weed invasion.

Tactical versus continuous stocking in perennial ryegrass-subterranean clover pastures grazed by sheep in south-western Victoria. 1. Stocking rates and herbage production

2001 ◽  
Vol 41 (8) ◽  
pp. 1099 ◽  
Author(s):  
R. A. Waller ◽  
P. W. G. Sale ◽  
G. R. Saul ◽  
G. A. Kearney
Keyword(s):  
Perennial Ryegrass ◽  
Dry Matter ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Stocking Rate ◽  
Soil Fertility Status ◽  
Western Victoria ◽  
Terminal Sire ◽  
Autumn And Winter ◽  
Stocking Rates

A 4-year field experiment was carried out in south-western Victoria to determine whether tactical stocking might improve perennial ryegrass (Lolium perenne L.) persistence and prime lamb production, compared with the more common practice of year-around continuous stocking. Tactical stocking consisted of variable length summer, autumn and winter rotations and continuous stocking in spring. The 2 grazing strategies were compared on 2 contrasting pastures: an upgraded pasture, sown with newer cultivars of perennial ryegrass and subterranean clover (Trifolium subterraneum L.) with 26 kg phosphorus/ha.year, and a more typical naturalised perennial ryegrass pasture receiving 6 kg phosphorus/ha.year. Paddocks were grazed by Border Leicester x Merino ewes, which were mated to a terminal sire to lamb in September. The effects of the grazing systems and pasture treatments on herbage production and stocking rate are presented in this paper. Herbage production was similar between the treatments, but tactical stocking significantly increased herbage mass during the growing season (P<0.05) compared with continuous stocking. In spring each year, the herbage mass generally exceeded 3000 kg dry matter/ha in tactically stocked paddocks and averaged 500–900 kg dry matter/ha higher than the mass on continuously stocked paddocks. This enabled the year-round stocking rate to be increased by an average of 9% over the 4 years of the experiment. We considered that the stocking rates could not be further increased, despite the higher herbage mass in spring, as stock reduced the dry herbage to a low residual mass by the opening rains in autumn. In contrast, stocking rates averaged 51% higher on the upgraded pasture compared with the typical pasture over the 4 years of the experiment. This indicates that pasture improvement and soil fertility status have a much greater impact on productivity than changes to grazing method. However, tactical stocking was able to increase the sustainability of prime lamb production on upgraded pastures in a dry summer climate, by maintaining herbage cover on the paddocks over the summer–autumn period.

scholarly journals Pasture growth on dairy farms in the Golden Bay and West Coast of the South Island

1998 ◽  
pp. 9-14
Author(s):  
K.L. Davis ◽  
N.A. Thomson ◽  
N.R. Mclean ◽  
D.A. Mccallum ◽  
R.J. Hainsworth ◽  
...  
Keyword(s):  
West Coast ◽  
Difference Method ◽  
Agricultural Research ◽  
Production Model ◽  
Research Station ◽  
Stocking Rate ◽  
The South ◽  
Financial Return ◽  
Pasture Production ◽  
The Difference

Pasture growth was monitored on 22 farms covering Golden Bay, Nelson, Murchison and West Coast districts during 1994 to 1997. Pasture growth was measured monthly from grazed pasture using the rising plate meter (RPM) and the difference method. Pasture growth from the South Island sites were compared with growth at the WestpacTrust Agricultural Research Station (WTARS) in South Taranaki, measured by the more traditional trim method, and the difference method as used in the South Island study. The pasture growth recorded was then used by the dairy farm production model UDDER to predict the planned start of calving (PSC), stocking rate and milksolids (MS) production at maximum net financial return for seven districts. At WTARS the average pasture production recorded by the difference method was 16.3 t DM/ ha and by the trim method, 12.9 t DM/ha, the greatest difference between the two methods occurring in late spring/early summer. Pasture production on the south Island sites varied from 9.6 (Taramakau) to 16.1 (Grey Valley) t DM/ha. The major factor identified as influencing pasture growth, in an environment where rainfall for 91% of the sites exceeded 2000 mm, was number of frosts. A multiple regression combining pasture production climatic and soil nutrient variables identified number of frosts and Olsen P as the major factors influencing pasture production (R2 = 0.25). The use of the growth from seven districts by UDDER showed a marked variation in management practices and MS output. PSC varied from the first 10 days in August (Takaka, Nelson, Westport) to the last 10 days in August (Murchison). Stocking rates ranged from 2.0 cows/ha at Motueka to 3.3 cows/ha on an irrigated farm in the Nelson district. MS production/ cow differed little among districts and MS production/ha reflected stocking rate, ranging from 650 kg/ha for Motueka to 1150 kg/ha for Nelson. The main factor driving stocking rate and PSC was winter pasture production. Keywords: climate, dairy production modelling, pasture production, soil fertility

Stocking rate and the superphosphate requirements of sown pasture on an acid soil

1968 ◽  
Vol 8 (30) ◽  
pp. 33 ◽  
Author(s):  
KD McLachlan
Keyword(s):  
Acid Soil ◽  
Grazing Intensity ◽  
Subterranean Clover ◽  
Growth Potential ◽  
Available Phosphorus ◽  
Similar Response ◽  
Stocking Rate ◽  
Pasture Production ◽  
Significant Difference ◽  
Stocking Rates

The response by Phalaris-subterranean clover pasture to applied nitrogen, phosphorus, and sulphur was measured at two sites on the same soil. Both sites had the same fertilizer history. For the past fifteen years the stocking rate on one site had been maintained at not less than three times that of the other. Yield responses to phosphorus were obtained at both sites. The response at the lower stocking rate was greater than that at the high stocking rate. A similar response pattern was found for nitrogen, but the difference in response between the stocking rate treatments was not significant. The pastures did not respond to sulphur. The trend was for sulphur to depress the yield at both stocking rates. The evidence suggests that less superphosphate was needed to maintain pasture production at high stocking rates than at low ones. Available phosphorus, determined chemically, increased with grazing intensity. There was no evidence that a particular soil phosphorus fraction was associated with this increase, or the lower requirement for added fertilizer. The only significant difference between grazing treatments were increases in the iron, calcium, and organic forms at the higher grazing intensity. It is probable that the present pasture response, and hence the fertilizer requirement of the soil, was influenced more by the altered growth potential of the plants under grazing, than by the effect of grazing on the soil nutrient status.

Melilotus albus (Medik.) is productive and regenerates well on saline soils of neutral to alkaline reaction in the high rainfall zone of south-western Victoria

2003 ◽  
Vol 43 (4) ◽  
pp. 349 ◽  
Author(s):  
P. M. Evans ◽  
G. A. Kearney
Keyword(s):  
Late Summer ◽  
Early Summer ◽  
Perennial Grasses ◽  
Saline Soils ◽  
Pasture Production ◽  
Pasture Legumes ◽  
Alkaline Reaction ◽  
Electrical Conductivities ◽  
Melilotus Albus ◽  
Western Victoria

Dryland salinity is a serious problem in Australia. While some introduced perennial grasses such as tall wheat grass (TWG) Thinopyrum ponticum (Podp. Z.W. Liu & R.R.C. Wang) are adapted to saline soils, there are few pasture legumes that are productive and persistent under saline conditions. Melilotus albus (Medik.) has the potential to be 1 such legume in southern Australia. To test the potential of this species, we conducted 2 experiments over a 3-year period on saline soils at Woorndoo and Glenthompson in south-western Victoria. The soil electrical conductivities (1 : 5 water) of the sites, in autumn before sowing, were 1–3 dS/m at Woorndoo and 3–5 dS/m at Glenthompson (0–10 cm depth).At both sites the herbage yields of 2 Melilotus lines were greater than 10 t/ha of dry matter for the whole season between autumn and late summer. The best commercial control species at Woorndoo, white clover cv. Haifa, produced less than 1/6 of the yield of the best Melilotus line during the summer months. At Glenthompson, during the whole second season the herbage yield of the best Melilotus was 40% greater than that of the best commercial control, Persian clover cv. Nitro plus. In the second season, regeneration of Melilotus at both sites was excellent, averaging 3500 seedlings/m2 at Woorndoo, and 1100 and 3400 seedlings/m2 in mixtures with TWG and in monoculture, respectively at Glenthompson. In the third season, however, regeneration averaged only 400 plants/m2 at Woorndoo and 640 plants/m2 at Glenthompson, both with and without grass. It appears that, when there is limited competition, Melilotus albus dominates in the first 2 years. However, as fertility and water use increase, other pasture species, which initially have a low rate of survival and are unproductive, begin to increase their presence in the sward at the expense of M. albus. These annual species germinate after the autumn rains dilute the salt on the surface of the soil and senesce in early summer as soil water deficits and/or evaporation increase the electrical conductivity again. We suggest that Melilotus albus is an excellent pasture legume to revegetate saline soils in southern Australia and represents an opportunity to obtain high levels of out-of-season pasture production from areas that are currently unproductive.

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