Herbicides for the control of grass weeds in pastures of Townsville stylo (Stylosanthes humilis)

1970 ◽  
Vol 10 (47) ◽  
pp. 790
Author(s):  
IMW Wood
Keyword(s):  
Dry Matter ◽  
Plant Population ◽  
Dry Matter Yield ◽  
Growing Period ◽  
Stylosanthes Humilis ◽  
Annual Grasses ◽  
Total Plant ◽  
Townsville Stylo

The use of herbicides to control annual grasses in pastures of Townsville stylo (Stylosanthes humilis) was studied at Katherine, N.T. The herbicides chlorthal, trifluralin, benefin, sindone B, and siduron all controlled the annual grasses Digitaria adscendens and Brachiaria ramosa. The outstanding herbicide was chlorthal, which at 6 lb a.i. an acre pre-emergence gave a Townsville stylo dry matter yield of 3250 lb an acre compared with 1130 lb an acre for the unweeded control and 2440 lb an acre for the handweeded control. At maturity there was no grass in the chlorthal plots and 1940 lb an acre in the unweeded control plots. The data suggest that, without defoliation during the growing period, total suppression of Townsville stylo can be expected when the grass population at establishment exceeds 37 per cent of the total plant population.

Effect of time of cessation of wet season grazing on Townsville stylo-annual grass pasture at Katherine, N.T

1973 ◽  
Vol 13 (64) ◽  
pp. 544 ◽  
Author(s):  
MJT Norman ◽  
LJ Phillips
Keyword(s):  
Dry Matter ◽  
Recovery Period ◽  
Dry Matter Yield ◽  
Annual Grass ◽  
Wet Season ◽  
Active Growth ◽  
Heavy Grazing ◽  
Stylosanthes Humilis ◽  
Dry Conditions ◽  
Townsville Stylo

A Townsville stylo (Stylosanthes humilis)-annual grass pasture at Katherine, N.T., was subjected to a series of treatments in 1969-70 and 1970-71 under which plots were grazed heavily from the beginning of the wet season for a period and then allowed to recover undefoliated for the remainder of the season. The dates at which heavy grazing ceased were spaced at 2-week intervals from November 24 to March 16. At the end of the wet season, total dry matter yield was linearly related to length of recovery period. Townsville stylo yield declined as recovery period was reduced from 18 to 8 weeks, but showed little response to a further reduction to 4 weeks. In contrast, annual grass yield showed little change as recovery period was reduced from 18 to 8 weeks, but fell with a further reduction to 4 weeks. As a result, the proportion of Townsville stylo in the pasture at the end of the season was high with long and short recovery periods but reached a minimum with an 8 - 10 week recovery period. Dry conditions prevailed in the first half of both seasons. The evidence suggests that young Townsville stylo is sensitive to heavy grazing when under water stress, and that early grazing for grass control should be imposed only during periods of active growth.

Wet season grazing of Townsville stylo pasture at Katherine, N.T

1970 ◽  
Vol 10 (47) ◽  
pp. 710 ◽  
Author(s):  
MJT Norman ◽  
LJ Phillips
Keyword(s):  
Dry Matter ◽  
Correlation Coefficients ◽  
Dry Matter Yield ◽  
Stocking Rate ◽  
Wet Season ◽  
Nitrogen Yield ◽  
Stylosanthes Humilis ◽  
Townsville Stylo ◽  
Using Data ◽  
Stocking Rates

At Katherine, N.T., stocking rates of 1.33, 1.00, and 0.67 Shorthorn steers an acre for a period of 18 weeks in the wet season beginning January were imposed on established pastures sown to Townsville sty10 (Stylosanthes humilis) alone but subsequently invaded to varying degrees by annual grasses. The experiment was repeated over three years. There were no significant differences in mean liveweight gain per head over three years ; hence liveweight gain per acre at the heaviest stocking rate was approximately twice that at the lightest rate. The mean dry matter yield of grass increased significantly with decreasing stocking rate, but there were no significant differences between stocking rates in Townsville stylo dry matter yield, nitrogen yield, or phosphorus yield. Correlation coefficients were calculated using data from individual paddocks and years. There was a highly significant positive correlation between liveweight gain per head and pasture nitrogen yield, and between liveweight gain per head and pasture phosphorus yield.

Effects of Planting Density on Leaf Area and Productivity of Two Maize Cultivars in Nigeria

1982 ◽  
Vol 18 (1) ◽  
pp. 93-100 ◽  
Author(s):  
S. U. Remison ◽  
E. O. Lucas
Keyword(s):  
Grain Yield ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Matter ◽  
Plant Population ◽  
Planting Density ◽  
Dry Matter Yield ◽  
Area Index ◽  
Positive Correlation ◽  
Maize Cultivars

SUMMARYTwo maize cvs, FARZ 23 and FARZ 25, were grown at three densities (37,000, 53,000 and 80,000 plants/ha) in 1979 and 1980. Leaf area index (LAI) increased with increase in plant population and was at a maximum at mid-silk. Grain yield was highest at 53,000 plants/ha. There was no relation between LAI and grain yield but there was a positive correlation between LAI and total dry matter yield.

Effect of time of sowing on flowering and growth of Townsville stylo (Stylosanthes humilis)

1974 ◽  
Vol 14 (67) ◽  
pp. 182 ◽  
Author(s):  
Mannetje L t ◽  
KHLvan Bennekom
Keyword(s):  
Low Temperatures ◽  
Dry Matter ◽  
Late Summer ◽  
Growing Season ◽  
Sowing Date ◽  
Stylosanthes Humilis ◽  
Maturity Type ◽  
Townsville Stylo ◽  
Late Start ◽  
Spring Sowing

A midseason maturity type of Townsville stylo sown at monthly intervals throughout a year in a glasshouse in Brisbane (27�30' south) started flowering from 42 to 76 days after sowing between February and September, with dry matter yields at flowering ranging from 0.05 to 5.82 g/per plant. Sowings between October and January resulted in flowering after 98 to 157 days, with yields ranging from 26.41 to 54.75 g/per plant. Flowering was mainly determined by daylength, although low temperatures during winter delayed inflorescence elongation. Growth after onset of flowering was measured in plants sown in winter, spring and late summer. Plant weights increased after flowering in all sowings. In the spring sowing this consisted entirely of stem and inflorescence, but in the other sowings leaf was formed after onset of flowering as well. Winter and spring sowings gave the highest, late summer sowing the lowest final yields. The main agronomic implication is that sowing early in the growing season is necessary for obtaining a good first year's yield, but that seed production is little affected by sowing date, ensuring good regeneration even in years with a late start of the growing season.

The effect of time of harvest on the yield components of poppies (Papaver somniferum L.)

1980 ◽  
Vol 95 (3) ◽  
pp. 667-676 ◽  
Author(s):  
J. C. Laughlin
Keyword(s):  
Dry Matter ◽  
Ground Level ◽  
Papaver Somniferum ◽  
Dry Matter Yield ◽  
Full Bloom ◽  
North West ◽  
Morphine Concentration ◽  
Commercial Harvest ◽  
Total Plant ◽  
Time Of Harvest

SUMMARYIn a field experiment in the north-west region of Tasmania, poppies (Papaver somniferum L.) were harvested at weekly intervals beginning 10 days after full bloom and continuing until 4 weeks after the dry commercial harvest stage. At each harvest the plants were cut off at ground level and partitioned into terminal capsules, lateral capsules, seed and the combined stem plus leaf component.The dry-matter yield of total plant and of all the components except seed achieved maximum values 2–3 weeks after full bloom and then progressively declined. For the total plant this decrease between maximum dry weight and that at the time of commercial harvest (8 weeks after full bloom) amounted to 26% while for terminal capsules it was 37% for lateral capsules 15% and for stem plus leaves 39%. In contrast, the dry-matter yield of total seed rose to a maximum by 4 weeks after full bloom and then remained constant for the duration of the experiment.The morphine concentration of both terminal and lateral capsules reached a maximum value of 1·1% 6 weeks after full bloom and then decreased by about 10% at the dry harvest stage. The morphine concentration of stem and leaves also reached a maximum of 0·1% about the same time as capsules but decreased rapidly and had halved by dry commercial harvest. The mutually compensating factors of decreasing dry-matter yield and increasing morphine concentration gave similar total plant morphine yields at any time of harvest from 2 to 7 weeks after full bloom. The morphine extracted from the whole plant at these times of harvest was about 50% greater than that derived from capsules alone at the time of dry commercial harvest.

Fire and survival of Stylosanthes spp. in the dry savanna woodlands of the Northern Territory

1982 ◽  
Vol 33 (2) ◽  
pp. 203 ◽  
Author(s):  
JJ Mott
Keyword(s):  
Dry Matter ◽  
Northern Territory ◽  
The Other ◽  
Dry Matter Yield ◽  
Stocking Rate ◽  
Wet Season ◽  
Native Grass ◽  
Hard Seed ◽  
Stylosanthes Humilis ◽  
Good Germination

A series of burns was carried out during the early and late, dry season and early wet season, in mixed native grass-legume plots containing Stylosanthes humilis, S. hamata, S, scabra and S. viscosa as the legume component. The least mortality was shown by S. scabra, but its survival was poor in any sward more than 3 years old. After burning the other species relied solely on seedling regeneration for subsequent season's growth. Fire killed a considerable quantity of seed, but its heat softened hard seed in the soil and good germination occurred with summer rains. However, the presence of a large proportion of soft seed through the winter months could lead to out-of-season germination and subsequent death of seedlings after unseasonal winter rains. Although the total dry matter yield of swards was reduced by all fires, burning could play an important part in increasing yields of S. hamata in swards overgrown by dense native grass, since it increases the amount of soft seed in the soil. If burning causes a high mortality of mature plants of the perennials S. scabra and S. viscosa, a reduction in stocking rate may be needed to ensure regeneration of a productive sward, as these species have slow seedling growth rates.

Effects of nitrogen fertilizer, plant population and irrigation on sugar beet: I. Yields

1971 ◽  
Vol 76 (2) ◽  
pp. 261-267 ◽  
Author(s):  
A. P. Draycott ◽  
D. J. Webb
Keyword(s):  
Sugar Beet ◽  
Nitrogen Fertilizer ◽  
Dry Matter ◽  
Sandy Loam ◽  
Plant Population ◽  
Sugar Yield ◽  
Dry Matter Yield ◽  
Plant Populations ◽  
Fertilizer Plant

SUMMARYFive experiments (1965–9) on calcareous sandy loam tested all combinations of four amounts of nitrogen (0–1·8 cwt/acre N) and four plant populations (8000–54 000 plants/ acre) given to sugar beet grown with and without irrigation. On average, nitrogen and plant population influenced yields greatly but irrigation relatively little. In all years between 0·6 and 1·2 cwt/acre N and between 17000 and 32000 plants/acre gave largest sugar yield. Giving more nitrogen or increasing the plant population neither increased nor decreased sugar yield much in any year. Irrigation was beneficial in only two out of five years.Sugar yield was linearly related to root dry-matter yield. Although total dry matter was greatest when the largest plant population was given the largest dressing of nitrogen and irrigation, the proportion of dry matter in the roots was decreased by all three factors.

The utilization and excretion of sulphur in cattle fed on tropical roughages

1974 ◽  
Vol 25 (6) ◽  
pp. 1015 ◽  
Author(s):  
PM Kennedy
Keyword(s):  
Fatty Acids ◽  
Organic Matter ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Small Decrease ◽  
Heteropogon Contortus ◽  
Total Sulphur ◽  
Stylosanthes Humilis ◽  
Digestible Organic Matter ◽  
Townsville Stylo

The effect of additions of sulphateh to the diet of cattle given tropical spear grass (Heteropogon contortus) and Townsville stylo (Stylosanthes humilis) was studied in three experiments. In one experiment there was a small increase in the digestibility of dry matter, but the intake of feed was not affected. The concentration of volatile fatty acids in ruminal liquor from cattle offered spear grass was increased by supplemental sulphate; there was a concurrent small decrease in the proportions of propionic and isovaleric acids. Excretion of faecal sulphur varied with the intakes of total sulphur, organic matter, and digestible organic matter, while urinary sulphur excretion varied with the sulphur and organic matter intakes. Excretion of organic sulphur and total sulphate in urine and faeces increased with sulphur intake. The ratio of nitrogen to sulphur in faeces declined when sulphate was given. The retention of nitrogen was correlated with sulphur retention. It was concluded that the intake and digestion of the hays were not limited by the intake of sulphur.

The effect of a phosphorus supplement on the performance of steers grazing Townsville stylo-based pasture in north Queensland

1977 ◽  
Vol 17 (86) ◽  
pp. 357 ◽  
Author(s):  
L Winks ◽  
FC Lamberth ◽  
PK O'Rourke
Keyword(s):  
Dry Season ◽  
Wet Season ◽  
Dry Tropics ◽  
Stylosanthes Humilis ◽  
Native Pasture ◽  
Weight Gains ◽  
Annual Grasses ◽  
Townsville Stylo

The effect of phosphorus supplementation on the performance of steeres grazing unfertilized native pasture and Townsville stylo (Stylosanthes humilis) with andwithout superphosphate fertilizer on the subcoastal spear grass region of the dry tropics of north Queensland was studied over a period of 40 months. Liveweight gains in the absence of supplementation on fertilized Townsville stylo pastures were greater than on unfertilized Townsville stylo, where performance was similar to that recorded on untreated native pasture. Phosphorus supplementation increased weight gains during the wet season on both unfertilized Townsville stylo and native pasture but had no significant effect on dry season performance or performance on fertilized Townsville stylo. Fertilized areas became dominated by annual grasses, Digitaria ciliaris and Brachiaria milliiformis, and legume yields were higher on unfertilized than on fertilized areas. Fertilizer improved the quality of available pastures.

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