Clover Dry Matter Research Articles

Nutritional restraints on subterranean clover grown on acid soils used for crop-pasture rotation

Lime, N and molybdenum fertilizers were used to establish how soil acidity limits the growth of subterranean clover (Trifolium subterraneum), in pot culture, on acid soils taken from north-east Victoria. The results indicate that two nutritional factors associated with the growth of subterranean clover are affected by excess acidity. These are manganese toxicity and ineffective nodulation of the clover. The plants grown on one unlimed soil (Rutherglen) had manganese concentrations and symptoms consistent with manganese toxicity. Liming the second soil (Lilliput) overcame a N deficiency by way of increased nodule formation. A third nutritional factor commonly associated with excess acidity, and found on the Lilliput soil, molybdenum deficiency, was not alleviated by the application of lime. Instead, the application of molybdenum fertilizer gave increases in clover dry matter production at all lime rates. In the absence of molybdenum fertilizer, the molybdenum concentration of the herbage was extremely low, irrespective of liming. These results are discussed in relation to already established field responses of subterranean clover to lime, and the management of the clover-ley system on the strongly acid soils.

Further studies on the effect of phosphate fertilizer and propyzamide on the growth of white clover slot‐seeded into permanent pasture

AbstractAssessments were made of the clover yield and clover content between early June and late July 1984 of white clover in a permanent pasture which had been slot‐seeded in spring 1982.Past reserves of phosphate or application of propyzamide alone only slightly increased clover dry matter yield but together they increased it from 13 to 785 kg dry matter ha‐1 and gave 31% clover in the total herbage yield. Applications of P2O5 during the experiment, alone or together with past reserves of phosphate, Iased clover yield from 13 to 242 kg dry matter ha‐1 and the proportion of clover from 1 to 10%. However, highest yields (1282 kg) and clover content (37%) were attained when P2O5 and propyzamide were applied to treatments with past reserves of phosphate.These results confirmed the trends evident during the second year and also indicated a potential role for grass‐suppressants in increasing management options during the early years after slot‐seeding.

Effect of lime on soil nitrogen uptake by a ryegrass-white clover pasture

Abstract The effect of liming (7.25 t/ha) on soil nitrogen (N) uptake was measured in a mixed rye-grass-white clover pasture over a 2-year period. Liming significantly increased ryegrass dry matter (DM) production by 8% but had no significant effect on clover or total DM production. Liming significantly increased the amount of soil N taken up by grass, and total soil N uptake increased by 50 kg N/ha over 2 years. The proportion of total soil N taken up by clover was positively related to the clover composition of the pasture, and was greatest in summer (30–40%) and least in winter (5–10%). The proportion of clover N derived from the soil ranged from 30 to 60%. Liming had no effect on the proportion of soil N taken up by clover or the proportion of clover N derived from the soil.

Effect of seed rate of red clover and of companion timothy or tall fescue on herbage production

AbstractTetraploid red clover (cv. Hungaropoly) was sown at seed rates of 6,12 or 18 kg ha−1 alone and in mixture with timothy (cv. Scots) at 2, 4 or 6 kg ha−1 or with tall fescue (cv. S170) at 6,12 or 18 kg ha−1. Two ‘silage’ crops and an ‘aftermath grazing’ crop were harvested in 2 successive years. In harvest years 1 and 2, total herbage production levels of 11.12 and 7.47 t dry matter (DM) ha−1 respectively were obtained from pure‐sown red clover compared with 11.84 and 8.78 t DM ha−1 for red clover‐timothy and 12.23 and 9.64 t DM ha−1 for red clover‐tall fescue. Corresponding red clover production levels were 10.93 and 5.30 t DM ha−1 (red clover swards), 8.04 and 3.131 ha−1 (red clover‐timothy), and 6.42 and 109 t ha−1 (red clover‐tall fescue).Total herbage organic matter digestibility was improved by the timothy companion grass but not consistently by the tall fescue, whereas crude protein (CP) concentration was decreased by the addition of either grass. Increased seed rate intensified these effects, as well as the general effect of the companion grass in depressing red clover DM, digestible organic matter (DOM) and CP production.Total herbage DM, DOM and CP were not markedly affected by increasing red clover seed rate but red clover DM, DOM and CP were increased as red clover seed rate was raised, due to increases in the red clover component.The potential for silage cropping of red clover swards was confirmed but there was advantage in sowing a companion grass. Taking yield and quality parameters into consideration, timothy proved a better companion than tall fescue. A seed rate of 2 or 4 kg ha−1 timothy and 12 kg ha−1 red clover proved the most satisfactory.

Forage and Nitrogen Contributions of Arrowleaf and Subterranean Clovers Overseeded on Bermudagrass and Bahiagrass1

AbstractTropical perennial grasses are the foundation of the pasture systems in the southeastern USA. However, they are low quality and require N fertilizer. Forage production and distribution and N accumulation of clover‐grass mixtures were compared to that of the grass alone receiving various rates of N fertilizer on a Crowley soil (fine, mortmorillonitic, thermic Typic Albaqualf). ‘Coastal’ bermudagrass [Cynodon dactylon(L.) Pers.] and ‘Pensacola’ bahiagrass (Paspalum notutumFlugge) sods were (i) overseeded with ‘Yuchi’ arrowleaf (Trifolium vesiculosumSavi) or ‘Mt. Barker’ subterranean clovers (Trifolium subterraneumL.), (ii) fertilized with 0, 84, 168, 252, or 336 kg N ha−1, or (iii) overseeded with arrowleaf or subterranean clover plus 112 kg N ha−1. Dry matter production of clover‐Coastal bermudagrass and clover‐bahiagrass mixtures was not significantly different from the grass alone at the 168 and the 252 kg N ha−1rate, respectively. Overseeding clovers improved seasonal forage distribution by providing forage one to two months earlier and reduced the May–June forage peak exhibited by the N fertilizer‐grass treatment. Average annual N accumulations of clover‐grass mixtures ranged from 177 to 217 kg N ha−1, which equaled or exceeded the 336 kg N rate except for the arrowleaf–bermudagrass mixture. The amount of N fertilizer required by the grass to replace the clover dry matter contribution was 127, 211, 160, and 254 kg N ha−1for the arrowleaf‐bermudagrass, arrowleaf‐bahiagrass, subterranean‐bermudagrass, and subterranean‐bahiagrass mixtures, respectively. Applying 112 kg N ha−1to clover‐grass mixtures did not improve total yield, forage distribution, or N accumulation, but did decrease percentage clover in the stand 5 to 33%.

WHITE CLOVER CULTIVAR EVALUATION FOR THE WAIKATO: ESTABLISHMENT PHASE

Nine white clover (Trifolium repens L.) cultivars were established in a field trial near Hamilton to assess their adaptability to high fertility, intensively managed dairy pastures in the Waikato. The data presented are for the establishment phase of a three-year trial on Horotiu sandy loam in which cultivars will be evaluated for their persistence, competitiveness and Nt-fixing ability in the presence of perennial ryegrass (Lolium perenne L.) and application of N fertiliser. Three entries from New Zealand were "Grasslands Huia", "Grasslands Pitau" and the Grasslands selection G18. Six cultivars from Europe were Aran, Blanca, Donna, Menna, Nesta and Sabeda. The cultivars represent a range of leaf sizes from medium-small to large. Aran and G18 (large leaved) generally developed stands with fewer thicker stolons than the other cultivars. Visual ratings of clover stand vigour during January to March 1983, . i.n.d.1,~a !e d that GiB had the greatest rate of estabiishment and ground cover despite its low stolon density. Perennial ryegrass seedling establishment was the least vigorous in G18 and Aran, and the most vigorous in Sabeda swards. Clover dry matter yields were generally highest for G18, Aran, Huia, Pitau and Donna, and lowest for Sabeda, Nesta and Menna. G18, Huia, Pitau, Eilanca and Donna maintained a higher clover content in the sward during the weedy establishment phase than the other cultivars. Keywords: Trifolium repens L., pasture establishment, white clover establishment.

Inoculation of white clover with different strains of Rhizobium trifolii on a mineral hill soil

SummaryS.184 white clover was established on an unimproved brown earth hill pasture using both surface seeding techniques and conventional cultivation. Inoculation with selected Rhizobium trifolii improved clover dry-matter production by 0·017 t/ha on the cultivated trial in the establishment year and by 0·13 t/ha in the first harvest year. On the uncultivated site, clover dry-matter production was increased 1·88 t/ha by the best inoculation treatment in the first harvest year and 1·01 t/ha in the second harvest year. Rhizobium strains differed in their ability to promote clover growth. Clover yields were substantially better on the uncultivated than on the cultivated trial. The implications of the results for hill land pasture improvement are discussed.

Allelopathic effects of white clover 1. Germination and chemical bioassay

Abstract Seed of 10 pasture species, germinated in the presence of an aqueous extract of freeze-dried white clover shoot material, showed inhibition of germination, and seedling abnormalities. A rate equivalent to 800 kg/ha of white clover dry matter (DM) almost totally inhibited the germination of white clover, alsike clover, cocksfoot, and perennial ryegrass seed. The addition of PVPP was able to remove up to 75% of observed inhibition. White clover plants grown in contrasting high country environments seldom produced levels of allelochemicals different to lowland white clover although summer-dry environments tended to promote allelochemical production. A chromatographic investigation implicated phenolics as the active allelochemicals.

Growth and N Fixation of Some Tropical Forage Legumes as Influenced by Solar Radiation Regimes1

AbstractDecreased solar radiation due to cloud cover or shading by plantation crops or associated grass can severely limit the production of tropical forage legumes. We therefore evaluated the response of six legumes (three replicated and three not replicated) to four radiation regimes (100, 70,45, and 27% of unshaded solar radiation, hereafter termed “full sun”) with polypropylene netting in the field.The three replicated legumes had significant yield reductions at 27% full sun, with intermediate reductions at 70 and 45%. Dry matter (DM) yields at full sun [metric tons (mt) ha,−1yr−1 and proportional yields at 27%] were: Desmodium intortum cv. Greenleaf (20.0, 46%); Centrosema pubescens ‘centro’ (13.7, 44%); and Macroptilium atropurpureum cv. Siratro (12.9, 20%). Greenleaf was relatively tolerantof moderate shading; proportional yields at 70 and 45% of full sun were 93 and 75%, respectively. Centro and Siratro yields declined linearly as shortwave radiation (hereafter termed “radiation”) decreased, but Siratro yields declined significantly more than centro. Marked seasonal differences were noted in the response of the legumes to shade, and this was attributed to differences in the ability of the legumes to utilize solar radiation during periods of cool temperatures. The three non‐replicated legumes were evaluated similarly, except that yields were adjusted for replication effects. Dry matter yields and proportional yields at 27% full sun were: Leucaena Ieucocephala cv. Hawaiian Giant (23.5, 40%); Stylosanthes guianensis cv. Schofield (17.0, 17%); and Desmodium canum ‘kaimi clover’ (12.2, 32%). Hawaiian Giant and Greenleaf yielded similarly at 45 and 27% full sun. Kaimi clover DM yield tended to be slightly higher (13.8) at 70% full sun, but thereafter yields declined linearly with reduced radiation. Schofield stylo was the most sensitive to shading.Dry matter and N concentrations were not significantly elevated by reduced radiation or cool weather except that N increased during the cool season. Concentrations of N differed among species being highest for centro and Hawaiian Giant (3.4%) and lowest for kaimi clover (2.6%). Total N yields were associated with DM yields. Nitrogen yields (kg N ha−1yr−1) of replicated legumes at full sun and proportional yields at 27% full sun were: Greenleaf (540, 45%), centro (461,44%), and Siratro (362,27%); and for the non‐replicated legumes, Hawaiian Giant (751,38%), Schofield (496, 18%), and kaimi clover [340 (361 at 70% full sun), 38%]. Acetylene reduction rates by nodules in soil cores were highly correlated with radiation regimes (r = 0.92‐0.995; except for centro, r = 0.71.) Correlation of acetylene reduction rates with DM yields ranged from 0.80 to 0.996.The higher yielding legumes, Greenleaf, centro, and Hawaiian Giant (plus kaimi clover for ≈70 % full sun only) appear well‐suited for areas of low solar radiation because they have relatively constant concentrations of DM and N and fixed significant quantities of N even under dense shade.

The effects of white clover mosaic virus infection on the yield of red clover (Trifolium pratenseL.) in mixtures and in pure stands

SUMMARYThe effects of white clover mosaic virus infection on the yield of two red clover varieties grown alone and in mixtures with either perennial or hybrid ryegrasses were examined. The spread of this virus within the pure clover plots was rapid. Clover drymatter yields were reduced and these losses were greater in the grass–clover mixtures than in the pure clover plots. Reductions in yield of about 70% were recorded at the first cut in mixtures of Sabtoron and Sabrina. The response of the clover to different levels of virus infection was best described by a negative linear relationship.Yields of Sabrina hybrid ryegrass increased as the levels of virus infection in the clover increased. This compensated for the losses in yield of the legume, leaving total sward yields unaffected by the virus.

Reseeding Crimson Clover as a N Source for No‐Tillage Grain Sorghum Production1

AbstractNitrogen fertilizer is an expensive but essential input for optimum production of non‐leguminous crops. The use of N fertilizer for summer grain crops can be reduced and possibly eliminated by double cropping with leguminous winter crops. Costs of seeding winter legumes, however, are often as expensive as the commercially produced N that they replace. Allowing the legumes to produce seed prior to planting the summer crop may potentially eliminate costs associated with seeding the legume each fall. The purpose of this field study, conducted on a Cecil sandy loam soil (Typic Hapludult), was to determine N fertilizer requirements for no‐tillage grain sorghum (Sorghum bicolor L. Moench) double cropped with reseeding crimson clover (Trifolium incarnation L.) and effects of N treatments on nutrient uptake and on insect populations. Nitrogen treatments were 0, 15, 30, 45, 90, and 135 kg N/ha and the clover tissue was either removed or left on the soil surface as a no‐tillage mulch.No‐till planting sorghum into clover or removing the clover top growth at maturity had no apparent effect on clover stand establishment the following fall. Clover dry matter production was essentially equal among years and averaged 4,762 kg/ha/yr. When averaged over years, the N, P, and K concentrations in the clovertops were 2.02, 0.24 and 2.40%, respectively. The only essential nutrient in sorghum leaves at the bloom stage affected by applied N was Cu which increased linearly as applied N increased. The only effects that removing clover had on nutrient content in the sorghum leaves were to reduce K in 1979 (from 2.47 to 2.31%), N in 1980 (from 2.85 to 2.69%) and P in 1979 (from 0.36 to 0.34%) and 1980 (from 0.34 to 0.29%). The reductions, however, were not sufficient to create a deficiency of either element. Some differences were found among common insect populations and their subsequent damage among treatments but the populations were not great enough to be considered economically damaging. Nitrogen produced by the clover was sufficient for maximum sorghum grain yield (5,760, 7,098, and 2,924 kg/ha in 1978, 1979, 1980, respectively) without supplemental applications of inorganic N. Removing the clover had no effect on sorghum grain yield in 1978 or 1979, but in 1980 this treatment reduced grain yield 601 kg/ha. Even though removing the clover which contained 62 kg/ha N in 1980 reduced sorghum yield, there was no response to applied N which suggests that the yield reduction was not due to a shortage of N.

Biological nitrogen fixation in upland and marginal areas of the U. K

The limitation of pasture, and hence livestock production, in the uplands of the United Kingdom by lack of available soil N is described. It is shown that fixation of 100-150 kg N ha -1 annually by white clover ( Trifolium repens ) is the key to sustained pasture improvement and to economically viable production systems so making agriculture less marginal in these areas. Some results of research on the nutrient, microbial and management requirements to establish and maintain upland pastures containing at least 25 % clover dry matter (d.m.) in the total herbage d.m. production in spring are illustrated. Enhanced N 2 fixation by white clover in upland agriculture will depend on increases in efficiency due to selection of rhizobia and rigid matching of them with clover genotype and the environment, on extension of the season offixation by choice of clover with low-temperature thresholds and by carefully controlled grazing of the swards, and on extension of the area of improved pasture. The potential for the latter alone is considerable since improvement of an additional 10% of the better upland soils by establishment of existing varieties of white clover and strains of Rhizobium would result in fixation of approximately 50 kt N annually, worth £20 M at today’s fertilizer prices.

PERFORMANCE OF A HILL COUNTRY WHITE CLOVER SELECTION

A white clover variety selected for New Zealand moist hill country was compared with three other white clover varieties in hill country at Ballantrae. Small plots of the hill country selection, Grasslands Huia, Grasslands Pitau, and the resident Ballantrae white clover were planted into paddocks receiving high or low superphosphate applications and three different managements - rotational grazing by cattle, rotational grazing by sheep, or set-stocked sheep for most of the year. Numbers of white clover stolons, white clover dry matter (DM) and total DM production, and proportion of white clover in cut herbage were determined twice yearly for three years. After one year of grazing the hill country selection consistently had approximately double the stolon numbers of Huia, a significantly higher proportion of clover in the herbage than Huia and clover DM yields 25-63% higher than Huia. These differences were not affected significantly by either management or soil fertility. Pitau and the local Ballantrae white clover were at no time more productive than Huia and frequently were poorer, although stolen numbers of the Ballantrae clover were usually higher during the trial and almost matched the selected variety after three years. The hill country selection is being multiplied for pre-release testing.

Competitiveness and persistence of introduced rhizobia on oversown clover: Influence of strain, inoculation rate and lime pelleting

Five strains of R. trifolii were evaluated, at two inoculation levels in the presence or absence of lime pelleting, for their ability to compete and persist in a tussock grassland soil containing a naturalized population of rhizobia. Effects on the growth of the oversown white clover ( Trifolium repens) were also investigated. Strains showed marked differences in their ability to form nodules on the host in competition with the naturalized population of rhizobia and also differed in their persistence over 15 months. The most competitive and persistent strain was PDDCC 2163 followed by 2153, 2666 and 2668 and the least competitive was 4144. Lime pelleting or increasing the rate of inoculation increased the competitive ability of strains. Strains that were highly competitive increased clover dry matter and N uptake.

Productivity of red clover grown alone and with companion grasses over a four‐year period

AbstractSix red clover cultivars, three diploid—Essex, Sabtoron and Violetta—and three tetraploid— Teroba, Red Head and Hungaropoly—were sown alone and with each of three companion grasses—timothy (S48), tall fescue (S170) and perennial ryegrass (S24). The productivity and persistency of the red clover cultivars were compared over 4 years. Dry matter (DM) yield, DM digestibility and the crude protein (CP) concentration were assessed and botanical analyses conducted on herbage samples from each treatment at each of three harvests per annum. Annual fertilizer application consisted of 165 kg P and 312 kg K ha‐1.Comparing clover cultivars alone Essex was significantly less productive and less persistent than the other five cultivars. Yield and persistency of the five other cultivars did not differ markedly within years with the exception that the diploids were significantly less productive than the tetraploids in the fourth year. Over all 4 years mean annual total DM and clover DM yields of the five cultivars were between 12·2 and 13·2 t ha‐1 and between 9·2 (79·2% of total DM yield) and 10·2 (83·2%) t ha‐1 respectively, and differences were not significant.Up to the end of the third year there was little or no advantage gained by the inclusion of a companion grass, annual total DM yields being between 11·2 and 14·2 t ha‐1 for clover alone and between 10·2 and 14·2 t ha‐1 for clover‐grass mixtures. In the fourth year there was an overall tendency for the yield of the clover alone to be lower, between 7·2 and 12·2 t ha‐1, than that of the clover‐grass mixture, between 8·2 and 13·2 t ha‐1, and this was more pronounced with the diploid than with the tetraploid clover cultivars. Sown with companion grasses, Essex and Hungaropoly were lower in yield and in contribution than the other cultivars over the 4 years. The influence of the companion grass on total dry matter yield showed that the contribution of timothy was low relative to that made by tall fescue and perennial ryegrass. Perennial ryegrass made the most varied contribution from year to year. Tall fescue was the most consistent contributor with all clover cultivars and at the end of 4 years both yield and clover‐grass balance had not changed materially.No pronounced differences in DM digestibility were evident between treatments.Crude protein concentration of the pure clover was similar to that of the clover‐timothy treatments and both would appear to be superior to either the clover‐perennial ryegrass or clover‐tall fescue mixtures.It is considered that red clover dominant swards are suitable for use under a cutting regime and can provide high yields of DM at a low cost for up to 4 years. Such swards are self‐sufficient in N and in addition soil N accumulation can be exploited in the production of succeeding crops.

THE POTENTIAL ROLE OF LEGUMES IN THE REHABILITATION OF LEVELLED GOLD DREDGE TAILINGS, TARAMAKAU RIVER, N.Z.

Recent increases in the value of gold have led to renewed interest in gold mining - particularly by the dredging of the river flats bordering West Coast rivers. In any future licensing of such dredging, the rehabilitation of the "destroyed" land will be a major consideration. Nitrogen is the main nutrient limiting the growth of radiata pine on the gold dredge tailings; this paper outlines initial results of an exploratory legume-fertilizer trial on levelled tailings in the Taramakau River valley. Twelve legume species were grown with and without superphosphate (+ MO, Mg and K). Tree lucerne (Cytisus proliferus) , Russell lupin (Lupinus polyphyllus) and yellow tree lupin (L. arboreus) grew well without the application of fertilizer but the pasture legumes had substantially increased dry matter production where P was added - in white clover (Trifolium repens) dry matter production was increased from 5.4 to 8.9 t/ha; and total N was 180 and 310 kg N/ha. Tree nutrition and growth were greatly improved by association with a vigorous legume species, In addition, the presence of legumes improved the appearance of the tailings and with a pasture species grazing potential was created

Symbiotic nitrogen fixation in a sequence of pastures of increasing age measured by a15N dilution technique

Abstract A 15N dilution technique was used to measure the uptake of soil nitrogen (N) by pasture herbage, and the rate and efficiency of symbiotic N fixation in four white clover (Trifolium repens)-based pastures ranging in age from 2 to > 20 years at Darfield, Canterbury. Pasture dry matter (DM) yields ranged from 9800 kg/ha/year in the youngest pasture to 6350 kg/ha/year in the oldest pasture. The proportion of clover DM decreased with increasing pasture age. The uptake of soil N by clover was 7–19% of the total N uptake and reflected the clover composition of the pastures. Rates of symbiotic N fixation were 45, 101, 78, and 142 kg N/ha/year for the pastures in order of decreasing pasture age. The efficiency of symbiotic N fixation, expressed in terms of the ratio N-fixed/total N in the legume, was greater in the two older pastures (87.6 and 87.7%) than in the younger pastures (81.6 and 82.3%).

The effect of grazing interval on the composition and productivity of a perennial ryegrass‐white clover sward

AbstractA ryegrass‐white clover sward was grazed by Welsh Mountain ewes with single lambs at a stocking rate of nineteen ewes per ha from April until October. Rotational grazing was practised and the treatments compared were rest periods of 3, 4 or 5 weeks.The percentage of ground covered by clover was estimated visually and quadrats were also cut to ground level to estimate the amount of clover dry matter present. A good correlation was obtained between these two estimates. Although the sward contained about 20% clover on visual assessment, the dry matter contribution was small.The amount of clover increased slightly over the season on all treatments, but the different rest periods of 21, 28 and 35 d made no significant difference to the amount of clover present.The growth rate of the lambs was also not significantly different between treatments.

A note on red clover silage for cattle finishing

ABSTRACTTrials were carried out over two winters to compare red clover and grass silage for cattle finishing.The silages were mixed to give rations containing 0,25,50,75 or 100% red clover dry-matter and were offered ad libitum to individually fed British Friesian-type steers. Significant differences in dry-matter intake occurred but the effect of silage type on animal performance was not significant. Barley supplementation had a significant effect on both total dry-matter intake and daily live-weight gain.

Effect of strains of Rhizobium trifolii on the establishment of oversown white clover ( Trifolium repens)

Strains of Rhizobium trifolii incorporated into commercial peat inoculants were compared for their effect on the establishment and growth of oversown white clover ( Trifolium repens) on soils devoid of infective rhizobia. There were marked differences in numbers of seedlings establishing and clover dry matter production per hectare with the various strains. However, when adjusted to a constant number of established seedlings, dry matter production from all strains, apart from one strain at one site, were similar indicating that the strains did not appear to influence the growth of individual clover plants. The marked differences in establishment of clover inoculated with the various strains could not be accounted for by differences in the number of rhizobia in the peat inoculant. Selecting strains of rhizobia for ability to increase establishment is considered important where clover is oversown onto soils devoid of rhizobia.