Effects of sowing method and competitor species and presence on Phalaris and Austrodanthonia establishment and persistence.

2000 ◽  
Vol 40 (6) ◽  
pp. 813 ◽  
Author(s):  
G. M. Lodge

Two experiments were conducted on plots sown in autumn 1992, at Tamworth in northern New South Wales. The first compared the establishment of 3 perennial grasses when sown as monocultures or with competitors in either broadcast-sown swards or alternate row-sown plots. Sowing rate and species of competitor were also examined as factors affecting perennial grass establishment. Perennial grasses were Austrodanthonia richardsonii (synonym Danthonia richardsonii) cv. Taranna, A. bipartita (synonym D. linkii) cv. Bunderra, and Phalaris aquatica cv. Sirosa. Competitors were Trifolium subterraneum var. brachycalycinum cv. Clare, T. repens cv. Haifa, and Lolium rigidum cv. Wimmera. In spring 1992, competitors were removed from 144 of the 288 plots to prevent them from seeding. A second experiment compared the longer-term (1993–96) dry matter yield and persistence of these perennial grasses under continuous grazing in plots were the competitor was present in year 1 (1992) or in all years (1992–96). In spring 1992, mean dry matter yield of perennial grass was higher (P<0.001) in row-sown plots then those sown by broadcasting. Mean dry matter yield of perennial grass was lowest at low sowing rate, but not significantly different at medium and high sowing rates (about 350 kg DM/ha). Compared with the monocultures, the presence of a competitor reduced mean perennial grass dry matter yields by 48, 69 and 85%, respectively for white clover, subterranean clover and annual ryegrass. Perennial grass plant numbers were highest (P<0.001) in the medium and high sowing rates of the monocultures and in white clover competitor plots and lowest (P<0.001) in all broadcast-sown plots, where annual ryegrass was the competitor. By spring 1996, white clover and annual ryegrass had declined to a low level in the pasture in all plots and the only major competitor was subterranean clover (1200 kg DM/ha, 40% plant frequency). Mean dry matter yields were highest (P<0.001) for Sirosa in 1993, but with dry conditions in 1994 and continuous grazing they were highest for Bunderra in all other years. The implications of these data for devising sowing strategies to maximise the establishment of perennial grasses and their long-term persistence in this environment are discussed.


2000 ◽  
Vol 51 (3) ◽  
pp. 377 ◽  
Author(s):  
G. M. Lodge

Seedlings of 3 perennial grasses, Danthonia linkii Kunthcv. Bunderra, D. richardsonii Cashmore cv. Taranna(wallaby grasses), and Phalaris aquatica L. cv. Sirosa,were each grown in replacement series mixtures with seedlings ofTrifolium repens L. (white clover),Trifolium subterraneum L. var. brachycalycinum (Katzn.et Morley) Zorahy & Heller cv. Clare (subterraneanclover), and Lolium rigidum L. (annual ryegrass). Plantswere sown 5 cm apart in boxes (45 by 29 by 20 cm) at a density of 307plants/m2. Maximum likelihood estimates were usedto derive parameters of a non-linear competition model using the dry matterweights of perennial grasses and competitors at 3 harvests, approximately 168,216, and 271 days after sowing. Intra-plant competition was examined inmonocultures of each species, grown at plant spacings of 2, 5, and 8 cm apartwith plants harvested at the above times.Competition occurred in all perennial grass–competitor mixtures, exceptin those of each perennial grass with white clover and thephalaris–subterranean clover mixture (Harvest 1) and those withD. richardsonii and phalaris grown with white clover(Harvest 2). For D. richardsonii (Harvests 1 and 2) andD. linkii (Harvest 1 only) grown with white clover andthe phalaris–subterranean clover (Harvest 1), the two species in themixture were not competing. In the phalaris–white clover mixture, eachspecies was equally competitive (Harvests 1 and 2). These differences incompetition and aggressiveness reflected differences in individual plantweights in monocultures where there was an effect (P < 0.05) of species ondry matter weight per box, but no significant effect of plant spacing.These data indicated that for successful establishment,D. richardsonii and D. linkiishould not be sown in swards with either subterranean clover or white clover,or where populations of annual ryegrass seedlings are likely to be high.Phalaris was more compatible with both white clover and subterranean clover,but aggressively competed with by annual ryegrass.



1972 ◽  
Vol 12 (57) ◽  
pp. 392 ◽  
Author(s):  
AA McGowan ◽  
IH Cameron

The effect of time of application of superphosphate on the dry matter produced from a subterranean clover (Trifolium subterraneum)annual grass pasture was studied. Treatments involved an annual topdressing of superphosphate, at 125 kg ha-1, in a particular month of the year, for each of the twelve months ; there was also an unfertilized control. In winter, dry matter yield was increased by 350-1190 kg ha-1 when superphosphate was applied at any time of the year. Winter yields were higher after application in January to May (mean 1570 kg ha-1) than in October to December (mean 1190 kg ha-1) or in June-July (mean 1230 kg ha-1). In spring, the greatest increases in dry matter yield were from topdressing in August or September (1600 and 1210 kg ha-1 respectively). Spring yields following application in other months were smaller but usually significantly greater than the yield of unfertilized pasture. The response to autumn application of superphosphate was much greater in winter than in spring. This was not due to a lower phosphorus requirement by the pasture in spring than in winter.



2004 ◽  
Vol 44 (12) ◽  
pp. 1165 ◽  
Author(s):  
A. M. Bowman ◽  
W. Smith ◽  
M. B. Peoples ◽  
J. Brockwell

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.



Author(s):  
A. Mills ◽  
D.J. Moot

Dry matter (DM) yields, botanical composition, liveweight production and pasture quality of six grazed dryland pastures established in 2002 at Lincoln University, Canterbury, are reported for Years 6 (2007/08) and 7 (2008/09). Lucerne (Medicago sativa) yielded 14.0 t DM/ha/yr and sheep liveweight (LW) production totalled 903 (2007/08) and 1 141 kg/ha/yr (2008/09). Metabolisable energy (ME) on offer (~134 GJ/ha/yr) and N yield (>500 kg/ha/yr) from the lucerne exceeded those of grass-based pastures. Yields (9.8- 11.2 t DM/ha/yr) and liveweight production (814-912 kg/ha/yr) from cocksfoot (Dactylis glomerata) pastures established with subterranean (Trifolium subterraneum) clover were greater than all other grass-based pastures. Annual ME was 79-96 GJ/ha and N yield was 269- 316 kg/ha from the cocksfoot, subterranean clover and volunteer white clover (T. repens) components. For Year 7, the contribution of unsown weeds and grasses in cocksfoot-based pastures was ~28% of total annual yield compared with 55% in ryegrass (Lolium perenne)/ white clover pastures. Consequently, the ME and N yields from sown pasture components in ryegrass/white clover pastures were lower than those from cocksfootbased pastures. These results indicate dryland farms with lucerne and/or cocksfoot/sub clover pastures can produce higher DM yields from more persistent pasture species. Persistence led to more ME and N on offer to grazing livestock, which resulted in higher liveweight production than from the ryegrass pastures. Keywords: balansa clover, Caucasian clover, growth rates, pasture quality, T. ambiguum, T. michelianum



1956 ◽  
Vol 7 (5) ◽  
pp. 367 ◽  
Author(s):  
WD Andrew ◽  
CA Neal-Smith

Over the period 1952-1954 there was no significant difference in the yield of herbage produced annually by the addition to a Phalaris tuberosa L.–Trifolium subterraneum L. pasture mixture, of any one of the following grasses: Agropyron obtusiusculum Lange., Bromus coloratus Steud., Bromus inermis Leyss., Dactylis glomerata L., or Festuca arundinacea Schreb. There were indications of a small change in seasonal production where certain grasses, notably D. glomerata, were included in the mixture. Over the 3-year period the proportion of the sown grass component, in the mixtures where either D. glomerata, B. inermis, or B. coloratus were included, increased by a greater amount than where the simple mixture of phalaris and subterranean clover was used. The addition of each grass also lessened the amount of P. tuberosa in the sown grass component of the yield. In the third year, despite the varying proportions of the phalaris and associated sown grass species, the mean population of the sown perennial grasses in each treatment did not differ significantly from the mean figure of 1.34 plants/sq. lk. The increased production of the sown grass yield component following the association of certain of the above species with P. tuberosa suggests that the latter does not fully exploit the environment. The principle of including another perennial grass when sowing phalaris and subterranean clover might have wide application as a means of combatting "phalaris staggers".



1965 ◽  
Vol 5 (16) ◽  
pp. 23 ◽  
Author(s):  
BR Watkin ◽  
PJ Vickery

Factors affecting the establishment and yields of legumes (Trifolium repens L., Trifolium subterraneum L., Meticago sativa L.) on unimproved pasture were studied on a granite soil in New England. Treatments included methods and times of sowing, pre-sowing grazing managements, and fertilizer applications. Sod seeding and discing increased the establishment of clover as did late sowing when the seed was broadcast. Pre-sowing grazing managements had no significant effects. Nitrogen application improved clover establishment. The percentage establishment for subterranean clover was consistently higher than that for white clover, but this was not related to subsequent yield. Sod seeding resulted in increased clover yields. Interactions between yields and pre-sowing grazing managements occurred with species ; light grazing before sowing resulted in maximum white clover yield whereas heavy grazing resulted in maximum subterranean clover and lucerne yields. Significant responses in the yield of white clover were obtained from phosphorus and potassium applications with a significant interaction (P x K). In the second year there were responses to phosphorus and sulphur, largely with repeat applications. The response to potassium declined in the second year. There was a significant increase in clover growth early in the second year from the application of lime and this interacted with potassium.



1989 ◽  
Vol 40 (2) ◽  
pp. 301 ◽  
Author(s):  
WD Bellotti ◽  
GJ Blair

'Demeter' tall fescue (Festuca arundinacea Schreb.) and 'Victorian' perennial ryegrass (Lolium perenne L.) were sown separately into a white clover (Trifolium repens L.) dominant pasture in June 1981. Eight sowing methods were compared to assess the ability of perennial grasses to establish from direct drill sowing methods relative to conventional seedbed and aerial sowing methods. Within direct drill treatments, two drill implements were factorially combined with three herbicide treatments. Pasture production and botanical composition were sampled over a 27 month period following sowing. After a dry summer, 22 months after sowing, sown grasses dominated pasture composition (69-94% of total dry matter yield) in the high yielding treatments. At this time, the successful direct drill treatments were similar in yield to the conventional seedbed treatment. Within direct drill treatments, sowing implement had little effect on yield and composition, whereas herbicide application markedly increased sown grass yield. Pre-sowing blanket application of herbicide in the triple disc treatment increased tall fescue yield from 82 to 1504 kg ha-1 and perennial ryegrass yield from 98 to 807 kg ha-1. An inverse relationship was described between dry matter present at sowing and eventual yield of sown grasses. These perennial grasses can be successfully established by using direct drill sowing methods provided resident vegetation is adequately suppressed.



1997 ◽  
Vol 48 (7) ◽  
pp. 977 ◽  
Author(s):  
Y. J. Ru ◽  
J. A. Fortune ◽  
W. D. Bellotti

In winter and early spring in Mediterranean environments, animal production is often limited by the low herbage availability associated with low growth rates and short swards, which result in low intake. In the present study, 26 subterranean clover (Trifolium subterraneum) cultivars were evaluated for herbage availability early in the season. There were large variations in dry matter yield (0·3-0·7 g/plant), sward height (2·9-9·3 cm), and leaf area index (1·0-5·1) among cultivars after 70 days of growth, indicating a possibility for selection of cultivars based on these parameters. Increasing plant density from 460 to 4600 plants/m2 increased dry matter yield from 88·5 to 362·8 g/m2 and sward height from 2·6 to 8·3 cm at Day 60. Early sowing increased dry matter yield, sward height, petiole length, leaf number, and leaf size by 13, 6, 32, 10, and 23%, respectively, after 70 days of growth. These results indicate that new pastures should be established early if soil moisture is adequate, and that the time of the season break has an important influence on early growth of pastures and, consequently, on the budgeting of feed in farming practice.



1972 ◽  
Vol 12 (57) ◽  
pp. 355 ◽  
Author(s):  
KFM Reed

August-born Corriedale lambs were weaned at ten weeks old and, for the following 12 months, were grazed on 16 plots. Each plot had been sown six years previously, to one of eight pasture mixtures which differed in their grass component, but not in their clover component. Trifolium perenne, Phalaris tuberosa, Dacylis glomerata, Trifolium repens, T . subterraneum, and T. fragiferum were sown. Hordem leporinum volunteered in most plots. Where perennial grass species were sown, Trifolium repens (white clover) contributed less than two per cent to the pasture present on the plots. For the two plots where perennial grass was not sown, white clover contributed up to 31 per cent. The total for all sown clover species present in the pasture varied from approximately 100 to 1000 kg ha-1, or approximately 3-30 per cent. Apart from the two plots where perennial qrass was not sown, the clover species present was mainly Trifolium subterraneum (subterranean clover). Average fleece weights varied from 3.1-4.9 kg on the different plots. The amount of sown clover present in the pasture accounted for 77 per cent of the between-plot variation in fleece weight and 66 per cent of the between-plot variation in annual liveweight gain. Measurements of pasture growth were made for four pasture mixtures. Total pasture growth showed differences of over 50 per cent due to pasture mixture, yet, when grazed at 20 weaners per hectare, differences in annual liveweight gain and fleece weight (10 months wool), due to pasture mixture, did not exceed 10 per cent. Annual liveweight gain and fleece weight were not correlated total pasture growth. However, pasture growth rate measured at monthly intervals, accounted for 43 per cent of the variation in mean daily liveweight gain during these individual months.



1994 ◽  
Vol 34 (4) ◽  
pp. 459 ◽  
Author(s):  
MAE Lattimore ◽  
HG Beecher ◽  
KL O'Callaghan

Four temperate clovers were grown on a typical rice-growing soil in the Murrumbidgee Valley, New South Wales, to assess their establishment and early growth potential. Subterranean clover (Trifolium subterraneum var. yanninicum) cv. Trikkala, Persian clover (T. resupinatum) cv. Maral, balansa clover (T. michelianum var. balansae) cv. Paradana, and white clover (T. repens) cv. Haifa were sown immediately following a rice crop in autumn of 3 consecutive years. Seven sowing methods were compared, including combinations of surface or drill sowing with land preparation techniques commonly used in rice-farming systems. All cultivars established successfully. Trikkala had the best establishment on the basis of per cent seed sown in year 2, and equal best in years 1 and 3, although Paradana and Maral had higher plant densities at the sowing rates used. Paradana and Maral produced the highest dry matter yields and Haifa the lowest (P<0.05) in the growing period to mid-spring. Sowing method strongly influenced (P<0.05) both establishment and yield of clover. Sowing into a dense rice canopy before harvest severely restricted clover performance, while harvesting rice before sowing greatly improved (P<0.05) clover establishment and dry matter production. Establishment from surface sowing was generally more successful than from drill sowing, although yields with both methods were mostly satisfactory. Establishment and yields were highest after burning stubble, but this effect was variable and not always significant. Sowing after cultivation was not successful, especially in the 2 wetter years, due to poor seedbed preparation and waterlogging.



Sign in / Sign up

Export Citation Format

Share Document