Clover and crop production under 13- to 15-year-old Pinus radiata

1979 ◽  
Vol 19 (98) ◽  
pp. 362 ◽  
Author(s):  
GW Anderson ◽  
FE Batini
Keyword(s):  
Pinus Radiata ◽  
Crop Production ◽  
Subterranean Clover ◽  
Growing Season ◽  
Tree Density ◽  
First Year ◽  
Adjacent Area ◽  
The Third ◽  
One Year ◽  
Seed Yields

A thirteen-year-old Pinus radiata plantation was thinned to 143 or 261 stems ha-1 and pruned to 6 m at Mundaring, Western Australia. The production of the Daliak, Seaton Park and Woogenellup cultivars of subterranean clover sown under the trees and on an adjacent area under pasture only was measured for two years. The yields of oats and lupins sown for two successive years following one year of clover pasture were also measured. No seedling establishment problems were encountered and healthy, productive pastures resulted. In the first year, Daliak was inferior to the other cultivars for both herbage and seed production. Seed yields were highest under the low tree density. By the third growing season herbage yields had fallen under the trees to 84% of the control pastures (4800 kg ha-1) at 143 stems ha-1 and 68% at 261 stems ha-1. The yields of oats were usually higher on the control plots but those of lupins seldom so.

The effects of length of growing season, with and without defoliation, on seed yield and hard-seededness in swards of subterranean clover

1981 ◽  
Vol 32 (5) ◽  
pp. 783 ◽  
Author(s):  
WJ Collins
Keyword(s):  
Seed Yield ◽  
Subterranean Clover ◽  
Growing Season ◽  
Absolute Scale ◽  
Growing Seasons ◽  
Short T2 ◽  
Relative Scale ◽  
Seed Yields

The effects of length of growing season and defoliation on seed yield and hard-seededness were examined in two strains of subterranean clover (Seaton Park, Midland B) grown in swards in the field. All plots were sown at the same time and the length of growing season was varied by altering the time of finish of the season (by withholding water). There were three length of growing season treatments: T1 (short), T2 (intermediate) and T3 (control). The defoliation treatments were D0, uncut (control), and D1, defoliated at weekly intervals until the commencement of flowering. Reducing the length of growing season drastically reduced seed yield. Thus when the growing season was only 3 weeks shorter than the control (i.e. T2 compared with T3), seed yields averaged over strains and defoliations were reduced by at least one half. With a further reduction of 2 weeks in the length of the season (T1) seed yields were only about one-third of those obtained in the control (T3). The reductions in seed yield were due to reductions in both the number of mature burrs produced and to a lesser extent in mean weight per seed. Although defoliation increased seed yield in all growing seasons, the effect when measured on a relative scale was greater in T2 than in either T1 or T3. But on an absolute scale the size of the response was greater in T2 and T3 than in T1. The rate of breakdown of hard-seededness was faster in Seaton Park than in Midland B, but it decreased in both strains with increasing length of growing season.

Seed production and persistence of Carnamah and other early strains of Trifolium subterraneum in the wheatbelt of Western Australia

1967 ◽  
Vol 7 (24) ◽  
pp. 25 ◽  
Author(s):  
GB Taylor ◽  
RC Rossiter
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Western Australia ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Growing Season ◽  
Early Flowering ◽  
The Other ◽  
Factors Affecting ◽  
Seed Yields

Seed production and persistence of the Carnamah, Northam A, Dwalganup, and Geraldton strains of subterranean clover (Trifolium subterraneum L.) were examined in undefoliated swards in the wheatbelt of Western Australia. The early flowering characteristic of Carnamah was not always associated with higher seed yields. Only when there was a well-defined, early finish to the growing season, or when flowering was very much earlier in Carnamah (viz., following an early 'break' to the season), did this strain clearly outyield both Northam A and Geraldton. The seed yield of Dwalganup was generally inferior to that of the other strains. Factors affecting regeneration are discussed. Under low rainfall conditions, poorer germination-regulation of Carnamah, compared with Geraldton and Northam A, would be expected to result in poorer persistence unless offset by higher seed yields in the Carnamah strain.

Effects of phosphorus on seed yields of subterranean clover, serradella and annual medics

1985 ◽  
Vol 25 (3) ◽  
pp. 595 ◽  
Author(s):  
MDA Bolland
Keyword(s):  
Seed Yield ◽  
Subterranean Clover ◽  
Average Weight ◽  
The Third ◽  
Hard Seeds ◽  
Annual Medics ◽  
Alternating Temperature ◽  
Seed Yields ◽  
The Relationship ◽  
Number Of Seeds

In three experiments located near Esperance, Western Australia, the effect of superphosphate phosphorus on seed yields of subterranean clover, serradella and annual medics was measured on newly-cleared soils, using low seeding rates. In two experiments, the relationship between seed yield and the amount of phosphorus applied was linear for subterranean clover and serradella; seed yields increasing by 7-24 kg/ha for each kg/ha of phosphorus applied, depending on species, strain or cultivar, and location. In the third experiment, seed yields of annual medic species also increased markedly with increasing amounts of applied superphosphate phosphorus, this response also depended on species and strain or cultivar, but the responses become less marked with increasing amounts of phosphorus. For the annual medic species, the phosphorus treatments had no effect on average weight of one burr, number of seeds per burr, weight of one seed, or the rate of softening of hard seeds as measured both in a 15/60� alternating temperature oven (one cycle/day) or for samples of burrs collected periodically during summer from the field. For all legumes, the appearance of first flowers was not affected by phosphorus treatment.

The Effect Of Grazing Compared With Cutting, at Different Frequencies, On a Lucerne-Cocksfoot Ley

1977 ◽  
Vol 88 (2) ◽  
pp. 483-492 ◽  
Author(s):  
D. Wilman
Keyword(s):  
Adverse Effect ◽  
Growing Season ◽  
N Content ◽  
The Third ◽  
Herbage Yield ◽  
Adjacent Site ◽  
One Year ◽  
Experimental Treatments ◽  
Harvest Year ◽  
Extreme Treatment

SUMMARYGrazing with sheep was compared with cutting, in each case at three frequencies, four, five and six defoliations per year, on a lucerne—cocksfoot ley. The treatments were applied in one year and their effects measured during that year and at cuts in June and August of the following year. One experiment began in 1963 in the second harvest year of a ley and a second began in 1964, on an adjacent site, in the third harvest year of the ley. Cutting four times in the year allowed lucerne to persist satisfactorily in both experiments. In the 1964 experiment cutting five or six times and grazing rather than cutting had no apparent, serious, adverse effect on the lucerne compared with cutting four times. In the 1963 experiment, however, increasing the number of cuts and grazing rather than cutting had a large adverse effect on the lucerne, and in the most extreme treatment, grazing six times, the proportion of lucerne was reduced to 2 % of total herbage yield the following June compared with 66% on the four-cut treatment. The contrasting results in the two experiments seem associated with weather differences, 1964 being a much drier, more sunny growing season than 1963, and perhaps with the differences in age of sward, individual lucerne plants perhaps having bigger roots with more reserves in 1964 than in 1963. During the treatment year increasing frequency of defoliation tended to increase the N content of both species and grazing compared with cutting generally increased the N content of cocksfoot. During the year following the treatment year the N content of the two species was little affected by the experimental treatments. The implications for farm practice are considered.

scholarly journals Budset and Growth of Eastern White Pine Following Application of 6-Benzylaminopurine to Seedlings Fertilized with Different Levels of Nitrogen

1988 ◽  
Vol 6 (2) ◽  
pp. 42-45
Author(s):  
L. Eric Hinesley ◽  
Robert D. Wright
Keyword(s):  
Irrigation Water ◽  
Pinus Strobus ◽  
Dry Weight ◽  
Growing Season ◽  
First Year ◽  
White Pine ◽  
Eastern White Pine ◽  
Growing Seasons ◽  
One Year ◽  
Different Levels

Eastern white pine (Pinus strobus L.) were potted and solution fed once weekly during 2 growing seasons with 5 levels of N in the irrigation water: 50, 100, 200, 300 and 400 ppm. Leaders were treated with 750 ppm 6-benzylaminopurine (BA) in late June of the first year. The higher N levels resulted in greater stem diameter, greater foliage dry weight, longer and heavier needle fascicles, better foliage color, greater budset after application of BA, and more and longer branches on the BA-treated leader the second growing season. BA should be applied to trees with N concentration ≥ 1.5% in one-year-old foliage.

scholarly journals Effect of Continuous Intensive Cultivation on the Chemical and Microbiological Properties of Oxic Dystrandept Soils in the Western Highlands of Cameroon

2021 ◽  
Vol 9 (1) ◽  
pp. 17-26
Author(s):  
NTANGMO TSAFACK Honorine ◽  
Keyword(s):  
Soil Fertility ◽  
Crop Production ◽  
Cropping Systems ◽  
Management Strategies ◽  
Chemical Properties ◽  
Available Phosphorus ◽  
First Year ◽  
Soil Productivity ◽  
One Year ◽  
Microbiological Properties

Soil fertility indices are well documented as they are directly related to land use and productivity. However, the effect of continuous intensive cultivation on the evolution of soil fertility is still poorly documented. The aim of this study was thus to assess the effect of continuous intensive cultivation on the chemical and microbiological properties of Oxic Dystrandept soils in the Western Highlands of Cameroon. Composite soil samples were taken between 0-15 cm depths on farmlands that have been subjected to continuous intensive cultivation for one, five and ten years meanwhile samples from plots that have never been cultivated served as control. The main results revealed that the ammonium contents dropped abruptly (86%-wt) from the first year of cultivation. The organic carbon (OC) content decreased from 1.81 ± 0.14 %-dm (in control) to 1.69 ± 0.09 % after one year, 1.66 ± 0.10 % after 5 years and 1.58 ± 0.07 % after 10 years. Compared to the control, available phosphorus (P) showed a 13 %-wt drop after one year, 46 % after 5 years and 85 % after 10 years. Dehydrogenase activity showed a 42 % decrease after one year, 50 % after five years and 73 % after 10 years. The other parameters were not significantly different (P<0.05) amongst treatments. Decline of soil productivity was undoubtedly related to the decrease of OC, P, microbial activity and ammonium with continuous intensive cultivation. Thus, management strategies for improved crop production should include selection suitable cropping systems and chemical methods. Keywords: Continuous intensive cultivation, enzymatic activities, soil chemical properties, Oxic Dystrandept, Cameroon western highland

scholarly journals Irrigation Cut-off Date Affects Growth, Frost Damage, and Yield of Jojoba

1993 ◽  
Vol 118 (6) ◽  
pp. 731-735 ◽  
Author(s):  
John M. Nelson ◽  
David A. Palzkill ◽  
Paul G. Bartels
Keyword(s):  
Water Potential ◽  
Seed Yield ◽  
Seed Weight ◽  
Frost Damage ◽  
First Year ◽  
Simmondsia Chinensis ◽  
Flower Bud ◽  
The Third ◽  
Second Year ◽  
Seed Yields

Flower bud injury resulting from freezing temperatures has been a major problem in jojoba [Simmondsia chinensis (Link) C. Schneid.] production. A 3-year field study, which began with 4-year-old plants, evaluated the effect of three irrigation treatments on growth, flower bud survival, seed yield, seed weight, and seed wax concentration of six clones. After 3 years, irrigation cut-off dates of late May (dry treatment) and early September (medium treatment) resulted in reduced plant height and width compared to irrigating through November (wet treatment). Flower bud survival and seed yields were very low in the first year for all treatments. In the second and third years, bud survival for most clones, even at -8C, was greatly improved by withholding water in the fall. In December of the second and third years, plants in the medium and dry plots had lower leaf water potential than those in the wet plot. In the second year, plants in the medium and dry plots had seed yields that were 3.5 times higher and wax yields that were were 2.3 times higher than plants in the wet plot. In the third year, the medium treatment had the highest seed and wax yields. Average seed weight and seed wax concentration were generally highest for plants in the wet plot where seed yields were low. Withholding irrigation from jojoba in the fall appears to improve flower bud survival and seed and wax yields following cold winters.

Seedbank Dynamics of Two Swallowwort (Vincetoxicum) Species

2017 ◽  
Vol 10 (2) ◽  
pp. 136-142 ◽  
Author(s):  
Antonio DiTommaso ◽  
Lindsey R. Milbrath ◽  
Scott H. Morris ◽  
Charles L. Mohler ◽  
Jeromy Biazzo
Keyword(s):  
United States ◽  
Management Strategy ◽  
Seedling Emergence ◽  
Soil Surface ◽  
Growing Season ◽  
First Year ◽  
Northeastern United States ◽  
The Third ◽  
Viable Seeds ◽  
Filled Seeds

Pale swallowwort and black swallowwort are European viny milkweeds that have become invasive in many habitats in the northeastern United States and southeastern Canada. A multiyear seedbank study was initiated in fall 2011 to assess annual emergence of seedlings and longevity of seeds of pale swallowwort and black swallowwort at four different burial depths (0, 1, 5, and 10 cm) over 4 yr. One hundred swallowwort seeds were sown in seed pans buried in individual pots, and emerged seedlings were counted and removed from May through September each year. A subset of seed pans was retrieved annually in October, and recovered seeds were counted and tested for viability. The majority of seedling emergence occurred during the first year (92% in 2012), and no new seedlings emerged in the third (2014) or fourth (2015) years. Pale swallowwort had relatively poor emergence at sowing depths of 0 cm (11%), 5 cm (6%), and 10 cm (0.05%—only one seedling), while 37% of pale swallowwort seeds emerged at 1 cm. The larger-seeded black swallowwort was more successful, with two-thirds of all sown seeds emerging at depths of 1 cm (71%) and 5 cm (66%), and 26% emerging at 10 cm. Only 16% of the surface-sown black swallowwort emerged. A large portion of the seeds that germinated at 10 cm, as well as at 5 cm for pale swallowwort, died before reaching the soil surface. Of filled seeds that were recovered in 2012 (black swallowwort at the 0-cm depth), 66% were viable. No viable seeds were recovered after the second growing season. Seeds recovered following the third year had become too deteriorated to accurately assess. Swallowwort seeds do not appear to survive more than 2 yr in the soil, at least in our experiment, suggesting that the elimination of seed production over 3 yr will exhaust the local seedbank. Seeds would need to be buried at least 10 cm for pale swallowwort but more than 10 cm for black swallowwort to prevent seedling emergence. Burial of swallowwort seeds as a management strategy may, however, only be practical in natural areas where high swallowwort densities occur.

Tree growth and nutrient cycling in dense plantings of hybrid poplar and black alder

1987 ◽  
Vol 17 (6) ◽  
pp. 516-523 ◽  
Author(s):  
B. Côté ◽  
C. Camiré
Keyword(s):  
N Uptake ◽  
Hybrid Poplar ◽  
Nutrient Content ◽  
Growing Season ◽  
First Year ◽  
Biomass Growth ◽  
Soil N ◽  
Black Alder ◽  
The Third ◽  
Poplar Growth

The cycling of N, P, K, Ca, and Mg was quantified during the third growing season in plantings (33 × 33 cm) of black alder (Alnusglutinosa (L.) Gaertn.) and hybrid poplar cv. Roxbury (Populusnigra L. × Populustrichocarpa Torr and Gray). First-year nutrient uptake, tree growth, and nutrient status of poplar were also assessed. During the 1st year, height and above-ground biomass growth of poplar were positively correlated with the proportion of alder in a plot. Poplar was twice as tall as alder in a mixed treatment and produced three times the aboveground biomass of alder in mixed plantings. On an individual tree basis, 1st year soil N uptake of alder averaged 46% of poplar N uptake. First-year winter dieback of poplar in this study prevented alder from being completely shaded by the poplars. Biomass growth and N status of poplar in the 2nd year were improved in mixed culture. After 3 years, accumulation of N and P in trees increased with the proportion of alder in a plot (maxima of 219 and 21 kg ha−1, respectively), but the greatest accumulations of N derived from the soil and K, Ca, and Mg were in mixed plantings (140, 88, 69, and 22.4 kg ha−1). Except for P, soil nutrient uptake during the third growing season was highest in plots with one alder for two poplars (maxima of 108, 9.1, 50, 60, and 19 kg ha−1 for N, P, K, Ca, and Mg). Throughfall nutrient content was not affected by species mixture. Except for Ca, nutrient content of total leaf litter increased with the proportion of alder (maxima of 80, 3.1, 13, 35, and 6.9 kg ha−1 for N, P, K, Ca, and Mg). After 3 years, no accretion of total N was detected in the soil, but exchangeable K increased 93% in the top 5 cm. Because stimulatory effect of interplanted alder on poplar growth decreased with time, reduced competition for soil N and light from the smaller alder during the first growing season were considered the most important factors in increasing individual poplar growth in our plantation.

scholarly journals Subterranean clover in North Canterbury sheep pastures

2003 ◽  
Vol 11 ◽  
pp. 189-192
Author(s):  
Tom and Anne Costello
Keyword(s):  
Seed Set ◽  
Subterranean Clover ◽  
Grazing Management ◽  
Meat Production ◽  
Key Factors ◽  
The 1960S ◽  
One Year ◽  
Clover Seed ◽  
The Cost ◽  
Seed Yields

The Hawarden basin is typified by dry, hot conditions over summer, which makes it difficult to retain ryegrass/white clover pastures on the lighter soils. These conditions have led to the introduction of better-adapted species such as the annual, subterranean clover. The mid-flowering cultivar 'Mt Barker' was first sown in the 1930s; then the earlyflowering 'Woogenellup' and late 'Tallarook' were used in the 1960s. The 'Mt Barker' type became dominant in these old pastures. The key factors for good subterranean clover growth were soil fertility (particularly P and S), space following dry summers for seedlings to re-establish, and moisture in the spring to maximise herbage yield. A visit to Australia in 1996 prompted the inclusion in new sowings of the late-flowering 'Leura' at high sowing rates (8-10 kg/ ha). It has taken 5 years for seed stocks to build to a level where we can identify good seedling strikes of 'Leura'. Two of the autumns over this period were very difficult and hindered normal establishment. Rainfall is erratic in North Canterbury, which affects the success of subterranean clover from one year to another. Dry summer conditions are optimal for subterranean clover strikes, as the pasture opens, and when the autumn break occurs, more than 2 000 subterranean clover seedlings/m2 can be produced. Autumn grazing management, when recovering from extreme drought, is critical because pasture must be spelled for 6 weeks to allow the subterranean clover to establish. However, if the autumn is wet, pasture cover must be controlled so that subterranean clover seedlings are not smothered. Set-stocking is best in spring to control pasture cover, but grazing should not be too hard during the flowering and seed set period. Subterranean clover seed yields of up to 250 kg/ha have been achieved from old pastures, but this is less seed than is produced under Australian conditions. Pasture renovation using the baker boot drill to re-introduce grasses and new cultivars of subterranean clover has been successful following very dry summers. Lamb growth rates have been excellent on subterranean clover-based pastures and these have increased the farm's meat production and reduced the cost of maintaining pastures. Key words: grazing management, North Canterbury, seedling establishment, seed set, subterranean clover

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