Herbage production and the accumulation of soil nitrogen under irrigated pastures on the Riverine Plain

1974 ◽  
Vol 14 (66) ◽  
pp. 49 ◽  
Author(s):  
CR Kleinig ◽  
JC Noble ◽  
AJ Rixon
Keyword(s):  
Perennial Ryegrass ◽  
Soil Nitrogen ◽  
White Clover ◽  
Accumulation Rate ◽  
Total Yield ◽  
Subterranean Clover ◽  
Nitrogen Accumulation ◽  
Total Soil ◽  
Total Soil Nitrogen ◽  
Applied Nitrogen

Herbage yield, herbage nitrogen, and soil nitrogen accumulation were followed over a five-year period (1958-63) under irrigated annual and perennial pastures established initially with different clovergrass proportions. Species sown in the annual pasture treatments were subterranean clover (Trifolium subterraneum cv. Tallarook) and annual ryegrass (Lolium rigidum cv. Wimmera). Those used in the perennial mixtures were white clover (T. repens cv. Irrigation) and perennial ryegrass (L. perenne cv. Victorian). In the treatments sown to annual or perennial ryegrass only, nitrogenous fertilizer as urea was applied annually at four rates. Total soil nitrogen (mat + 0-91 cm of soil) after five years did not differ significantly for annual pasture and bare ground. In contrast, total soil nitrogen under all perennial pasture treatments, particularly those with a white clover component, was significantly greater than for bare soil (5365 cf. 4181 kg ha-1). Where white clover was sown, nitrogen accumulated at the rate of 258 kg ha-1 per annum compared with 101 kg ha-1 per annum under subterranean clover, the latter barely matching the accumulation rate under perennial ryegrass sown alone without applied nitrogen (105 kg N ha-1 p.a.). Nitrogen accumulation (soil plus mat) was related to both legume and non-legume nitrogen. Perennial pasture, particularly if white clover was present, generally outyielded annual pasture. The total yield of white clover over five years was 29,970 kg ha-1 compared with 11,614 kg ha-1 for subterranean clover. Annual and perennial ryegrasses showed similar yield responses to applied nitrogen. Irrespective of the rate of urea application, nitrogen recovery was low (21-23 per cent).

Effect of Prescribed Burning of Forest Litter on Total Soil Nitrogen

1962 ◽  
Vol 26 (2) ◽  
pp. 200-202 ◽  
Author(s):  
J. O. Klemmedson ◽  
A. M. Schultz ◽  
H. Jenny ◽  
H. H. Biswell
Keyword(s):  
Soil Nitrogen ◽  
Prescribed Burning ◽  
Forest Litter ◽  
Total Soil ◽  
Total Soil Nitrogen

Early spring and late autumn response to applied nitrogen in four grasses

1980 ◽  
Vol 94 (2) ◽  
pp. 443-453 ◽  
Author(s):  
D. Wilman ◽  
A. A. Mohamed
Keyword(s):  
Perennial Ryegrass ◽  
Leaf Blade ◽  
Unit Area ◽  
Total Yield ◽  
Early Spring ◽  
Late Winter ◽  
Number Of Leaves ◽  
Four Levels ◽  
Leaf Extension ◽  
Applied Nitrogen

SummaryThe regrowth of Aberystwyth S. 23 perennial ryegrass, S. 24 perennial ryegrass, S. 59 red fescue and S. 170 tall fescue was studied in field swards, comparing four levels of applied nitrogen, for 8 weeks following a clearing cut. The clearing cuts were in mid-October, mid-February and mid-March in each of 3 years, different plots being used on each occasion.The application of N increased the number of leaf primordia, the number of un-emerged leaves, the rate of leaf emergence and death, leaf blade length, width and weight, sheath length, number of leaves per unit area of ground and proportion of green tissue in total yield. The application of N had little effect on the number of leaves per tiller and tended to reduce weight per unit area of leaf blade. The increase in size, weight and number of leaf blades appeared to be major reasons for the positive effect of applied N on yield, previously reported; and the increase in sheath length contributed to the increase in proportion of yield above 4 cm. Rate of leaf extension was not closely related to yield and was more sensitive to temperature than was yield. Changes during regrowth in blade and sheath length helped to explain changes in weight per tiller, previously reported. The effects of improving weather conditions in late winter/early spring were similar to the effects of applied N: larger, heavier leaf blades, longer sheaths, a taller canopy, a lower proportion of dead material, younger leaves. The length of shoot apex per leaf primordium was relatively constant. Leaves continued to emerge, at a slow rate, in the period December–February. S. 170 had the biggest leaves, particularly in May, and the slowest rate of leaf turnover. Rate of leaf extension was increased by applied N more, on average, in the ryegrasses than in the fescues.

scholarly journals The effect of dairyshed effluent irrigation on the occurrence of plant pathogenic Pythium species in pasture

2000 ◽  
Vol 53 ◽  
pp. 436-440 ◽  
Author(s):  
N.W. Waipara ◽  
S.K. Hawkins
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Subterranean Clover ◽  
Preliminary Survey ◽  
Pythium Species ◽  
Effluent Irrigation ◽  
Pathogenicity Tests ◽  
Roots In Vitro

A preliminary survey of pastures sprayirrigated with dairyshed effluent revealed a significant increase in the population of plant pathogenic Pythium species isolated from both soil and roots In vitro pathogenicity tests showed the majority of these isolates to be pathogenic when inoculated onto the seedlings of white clover subterranean clover and perennial ryegrass although both clover species were more susceptible to Pythiuminduced disease than ryegrass

Leys and soil organic matter:III. The accumulation of macro-organic matter in the soil under different swards

1972 ◽  
Vol 78 (2) ◽  
pp. 333-341 ◽  
Author(s):  
E. A. Garwood ◽  
C. R. Clement ◽  
T. E. Williams
Keyword(s):  
Organic Matter ◽  
Soil Carbon ◽  
Perennial Ryegrass ◽  
White Clover ◽  
Arable Land ◽  
N Fertilizer ◽  
Plant Debris ◽  
Total Soil ◽  
Grazed Swards ◽  
Mesh Sieve

SUMMARYMacro-organic matter (roots and partially decomposed plant debris retained on a 0·25 mm mesh sieve) was measured in soils under various swards. Under a grazed perennial ryegrass/white clover sward, sown on arable land, macro-organic matter in the top 15 cm of soil rose steadily in the first 8 years to 15·8 t/ha, but subsequently declined. Under arable cropping there was great variation with crop and season. Under grass, most of the macro-organic matter accumulated in the top 2 cm of soil, particularly during the first 3 or 4 years. More macro-organic matter was found under perennial ryegrass/white clover than under cocksfoot/white clover swards.After 3 years under grass macro-organic matter accounted for 10% of the total soil carbon, and represented about half the increase in soil carbon.Half, or less, of the nitrogen which accumulated in soil under grass was in the macroorganic matter fraction. The differences between swards which received no N fertilizer and those which received 940 kg/ha over 3 years was small, 16–40 kg N/ha respectively for cut and frequently grazed swards. The ratio of C:N in macro-organic matter under different swards averaged 22:1.

A comparison of silages made from red clover/grass, white clover/grass and high nitrogen grass swards for beef production

1985 ◽  
Vol 40 (2) ◽  
pp. 267-277 ◽  
Author(s):  
T. A. Stewart ◽  
I. I. McCullough
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Dry Matter ◽  
Total Yield ◽  
Live Weight ◽  
Red Clover ◽  
Dry Matter Yield ◽  
Grass Silage ◽  
Matter Production ◽  
Grass Sward

ABSTRACTSilage cut twice annually (June and August) from a tetraploid red clover/grass sward and three times annually (May, July and September) from a low nitrogen (N) and high N perennial ryegrass/white clover sward was fed in proportion to dry-matter yield from each cut, over a 10-week period, each winter for 3 years to castrated male cattle of initial live weight 401 kg in year 1 and 425 kg in years 2 and 3. The silages were supplemented with 0, 1, 2 and 3 kg concentrate per head daily.Total dry-matter yield from the red clover/grass sward was similar to that from the perennial ryegrass/white clover sward (high N grass) receiving 360 kg N per ha but the digestibility, particularly of first cut material was much lower. Dry-matter production of the low N grass/white clover sward was 0·73 of high N grass sward and produced silages of similar digestibility and fermentation.Dry-matter intakes by the cattle were higher on the legume-based silages in years when clover made a worthwhile contribution to total yield, but this did not significantly improve utilization or animal performance compared with high N grass silage. Mean daily carcass gain per head on red clover/grass silage was 0·41 kg which was significantly less than the 0·61 kg on white clover/grass silage and 0·59 on high N grass (P < 0·001). Carcass output from red clover/grass silage was 618 kg/ha and 629 kg/ha from white clover/grass, both of which were significantly less than the 863 kg/ha from the high N grass silage (P < 0·001). Dressing proportion was also significantly poorer in animals fed red clover/grass silage compared with the other silage types.

The cobalt status of Tasmanian soils. II The recovery of applied cobalt in pot experiments

1964 ◽  
Vol 15 (4) ◽  
pp. 609 ◽  
Author(s):  
KD Nicolls ◽  
JL Honeysett
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Plant Material ◽  
Acid Soils ◽  
Subterranean Clover ◽  
Cobalt Content ◽  
Pot Experiments ◽  
Ph Range

In glass-house experiments, cobalt was added at rates corresponding to 18, 32, or 36 oz CoSO4.7H2O per acre to 27 soils, mostly krasnozems. This treatment raised the cobalt content of subterranean clover tops significantly on only 13 soils, and on only five of the 13 by more than 0.05 p.p.m. Cobalt in control plants ranged from 0.05 to 0.32 p.p.m. The largest recovery of applied cobalt, by two successive crops of subterranean clover, was 4% of that applied. Mechanical contamination of plant material was avoided by adding the cobalt before sowing the first crop. Perennial ryegrass and white clover gave similar results, over four or five harvests. The implications for the practice of top-dressing pastures with cobalt salts are discussed. Cobalt application at the 36 oz rate increased cobalt in subterranean clover more than the 18 oz on three of the four soils tested at the two rates. There was some evidence for a greater recovery of applied cobalt from the more acid soils, over a pH range of 4.9 to 6.2.

The effects of some grazed tropical grass-legume mixtures and nitrogen fertilized grass on total soil nitrogen, organic carbon, and subsequent yields of Sorghum vulgaris

1967 ◽  
Vol 7 (24) ◽  
pp. 66 ◽  
Author(s):  
RJ Jones
Keyword(s):  
Organic Carbon ◽  
Soil Nitrogen ◽  
Crop Yields ◽  
Low Fertility ◽  
Apparent Lack ◽  
Carbon And Nitrogen ◽  
Total Soil ◽  
Significant Difference ◽  
Nitrogen Treatments ◽  
Total Soil Nitrogen

Mixtures of some tropical legumes and Paspalum plicatulum (Michx) cv. Hartley, and stands of P. plicatulum were fertilized with urea at 100 and 200 lb nitrogen an acre a year, and were intermittently grazed by cattle over a period of four years. Soil analyses for organic carbon and for total soil nitrogen in the fourth year of the pasture phase revealed large treatment effects in three of the five replicates. These three replicates which were on a podsolic soil were lower in fertility than the remaining two on a latosolic soil. Soil nitrogen at the 0-3 inch depth in the high nitrogen treatment, and in two Phaseolus atropurpureus D.C. treatments was significantly higher than the control (P<0.05). Organic carbon at the 0-3 inch depth was significantly higher than the control (P<0.05) in the nitrogen treatments and in one of the P. atropurpureus treatments. For both soil nitrogen and organic carbon the Lotononis bainesii Bak. treatment did not differ from the control. There was no significant difference between treatments for soil nitrogen or organic carbon at the 3-6 inch depth though trends were similar to those at 0-3 inches. Organic carbon and nitrogen were closely correlated for all treatments at both depths, and there were no significant differences in the C : N ratio in any treatment. Yields of sorghum grown as a test crop after the pastures were significantly correlated with soil nitrogen values in the three low fertility replicates. A high correlation (r = +0.976) also existed between yields of nitrogen obtained in the pasture phase and test crop yields of nitrogen for all treatments except L. bainesii. Reasons for the apparent lack of improvement in soil nitrogen and carbon on the higher fertility replicates and for the poor test crop yields following L. bainesii are discussed.

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