Long-Term Persistence of Cool-Season Grasses Planted to Suppress Broom Snakeweed, Downy Brome, and Weedy Forbs

Long-term control of downy brome with an integrated approach is needed in order to sustain range productivity. Studies were conducted to study the effectiveness of a combination of downy brome control practices. In two studies, glyphosate and paraquat were evaluated at various rates for up to three successive years for control of downy brome in rangeland. A third study evaluated the competitiveness of perennial cool-season grasses against downy brome in the absence of herbicides. Glyphosate, at 0.55 kg/ha, and 0.6 kg/ha paraquat provided selective downy brome control on rangeland when applications were combined with intensive grazing. Downy brome control was greater than 90% following two sequential years of 0.6 kg/ha paraquat at either the two- to eight-leaf stage or bloom stage at both study locations. At one study location, 0.55 kg/ha glyphosate provided 97% control after the first application at both growth stages. In the second study, control averaged greater than 92% following three sequential applications of glyphosate. When perennial cool-season grasses were seeded in the spring following fall tillage (no herbicides) and allowed to establish for three growing seasons, three of the five species were effective in reducing the reestablishment of downy brome. ‘Luna’ pubescent wheatgrass, ‘Hycrest’ crested wheatgrass, ‘Sodar’ streambank wheatgrass, ‘Bozoisky’ Russian wildrye, and ‘Critana’ thickspike wheatgrass controlled 100, 91, 85, 45, and 32% of the downy brome, respectively. Yields of perennial grass dry matter were 1,714, 1,596, 1,135, 900, and 792 kg/ha. Replacing noncompetitive annual grasses with competitive cool-season perennials will provide a longer term solution to a downy brome problem than the use of herbicides alone or with intensive grazing.

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Evaluation of the CERES-Rice Model for Precision Nitrogen Management for Rice in Northeast China

Advances in Animal Biosciences ◽

10.1017/s2040470017000024 ◽

2017 ◽

Vol 8 (2) ◽

pp. 328-332

Author(s):

J. Zhang ◽

Y. Miao ◽

W.D. Batchelor

Keyword(s):

Northeast China ◽

Weather Data ◽

Cool Season ◽

Use Efficiency ◽

Optimum N Rate ◽

Management Recommendations ◽

N Management ◽

N Rates ◽

N Use

Over-application of nitrogen (N) in rice (Oryza sativaL.) production in China is common, leading to low N use efficiency (NUE) and high environmental risks. The objective of this work was to evaluate the ability of the CERES-Rice crop growth model to simulate N response in the cool climate of Northeast China, with the long term goal of using the model to develop optimum N management recommendations. Nitrogen experiments were conducted from 2011–2015 in Jiansanjiang, Heilongjiang Province in Northeast China. The CERES-Rice model was calibrated for 2014 and 2015 and evaluated for 2011 and 2013 experiments. Overall, the model gave good estimations of yield across N rates for the calibration years (R2=0.89) and evaluation years (R2=0.73). The calibrated model was then run using weather data from 2001–2015 for 20 different N rates to determine the N rate that maximized the long term marginal net return (MNR) for different N prices. The model results indicated that the optimum mean N rate was 120–130 kg N ha–1, but that the simulated optimum N rate varied each year, ranging from 100 to 200 kg N ha–1. Results of this study indicated that the CERES-Rice model was able to simulate cool season rice growth and provide estimates of optimum regional N rates that were consistent with field observations for the area.

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Cropping Systems to Control Winter Annual Grasses in Winter Wheat (Triticum aestivum)

Weed Technology ◽

10.1017/s0890037x00045012 ◽

1999 ◽

Vol 13 (1) ◽

pp. 120-126 ◽

Cited By ~ 32

Author(s):

Oleg Daugovish ◽

Drew J. Lyon ◽

David D. Baltensperger

Keyword(s):

Winter Wheat ◽

Cropping Systems ◽

Field Studies ◽

Downy Brome ◽

Jointed Goatgrass ◽

Long Term Effect ◽

Annual Grasses ◽

Winter Annual ◽

Feral Rye

Field studies were conducted from 1990 through 1997 to evaluate the long-term effect of 2- and 3-yr rotations on the control of downy brome, jointed goatgrass, and feral rye in winter wheat. At the completion of the study, jointed goatgrass and feral rye densities averaged 8 plants/m2and < 0.1 plant/m2for the 2- and 3-yr rotations, respectively. Downy brome densities averaged < 0.5 plant/m2for both the 2- and 3-yr rotations, with no treatment differences observed. Winter annual grasses were not eradicated after two cycles of the 3-yr rotations, but weed densities were reduced 10-fold compared to densities after one cycle and more than 100-fold compared with the 2-yr rotations. Wheat grain contamination with dockage and foreign material followed a similar trend. The 3-yr rotations were economically competitive with 2-yr rotations and provided superior control of the winter annual grass weeds.

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THE RAINFALL INDEX ANNUAL FORAGE PILOT PROGRAM AS A RISK MANAGEMENT TOOL FOR COOL-SEASON FORAGE

Journal of Agricultural and Applied Economics ◽

10.1017/aae.2016.3 ◽

2016 ◽

Vol 48 (1) ◽

pp. 29-51 ◽

Cited By ~ 7

Author(s):

JOSHUA G. MAPLES ◽

B. WADE BRORSEN ◽

JON T. BIERMACHER

Keyword(s):

Management Tool ◽

Pilot Program ◽

Cool Season ◽

Term Study ◽

Rainfall Index ◽

Long Term Study ◽

Adequate Coverage ◽

Highly Correlated ◽

Risk Protection

AbstractThe recently implemented Rainfall Index Annual Forage pilot program aims to provide risk coverage for annual forage producers in select states through the use of area rainfall indices as a proxy for yield. This article utilizes unique data from a long-term study of annual ryegrass production with rainfall recorded at the site to determine whether the use of rainfall indices provides adequate coverage for annual forage growers. The rainfall index is highly correlated with actual rainfall. However, it does not provide much yield loss risk protection for our cool-season forage data.

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IMPROVEMENT OF FORAGE QUALITY THROUGH PRODUCTION MANAGEMENT AND PLANT BREEDING

Canadian Journal of Plant Science ◽

10.4141/cjps83-113 ◽

1983 ◽

Vol 63 (4) ◽

pp. 895-902 ◽

Cited By ~ 8

Author(s):

R. E. HOWARTH ◽

B. P. GOPLEN

Keyword(s):

Plant Breeding ◽

Production Management ◽

Forage Quality ◽

Analytical Techniques ◽

Nutrient Content ◽

Forage Production ◽

Cool Season ◽

Grazing Systems ◽

Forage Management

The prospects for improving forage quality through improved management of forage production and through plant breeding are reviewed, with emphasis on the Canadian situation. The major components of forage quality are nutrient content, digestibility, voluntary intake, and lack of anti-nutritive factors. Since maturity has a major impact on forage quality, adequate harvest systems and equipment are essential for consistent production of quality forage. Legume forages are generally of higher quality than grasses. Greater use of legumes and improved procedures for renovation of grass-legume mixtures provide opportunities for improved forage quality. Greater use of complementary and rotational grazing systems should enhance intake of quality forage. Breeding for improved forage quality is a slow, long-term approach, but relatively small improvements in digestibility can give substantial improvements in animal productivity. Breeding for improved quality should continue with emphasis on anti-nutritive factors and intake of digestible energy. Progress in breeding the cool-season forages for improved quality has been impaired by inadequate analytical techniques. Analytical methods used in nutrition laboratories may require modification or adaptation to meet the unique requirements of plant breeders.Key words: Forage, management, breeding, quality, digestion

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Selective Nimblewill (Muhlenbergia schreberi) Control in Cool-Season Turfgrass

Weed Technology ◽

10.1614/wt-07-016.1 ◽

2007 ◽

Vol 21 (4) ◽

pp. 886-889 ◽

Cited By ~ 9

Author(s):

John B. Willis ◽

Josh B. Beam ◽

Whitnee L. Barker ◽

Shawn D. Askew ◽

J. Scott McElroy

Keyword(s):

Initial Treatment ◽

Creeping Bentgrass ◽

Single Application ◽

Cool Season ◽

Selective Control ◽

Control Options

Isoxaflutole and mesotrione have been used to control creeping bentgrass in cool season turf, these experiments evaluate these two products for selective nimblewill control. Three experiments were conducted in Virginia and Tennessee to evaluate selective control options for nimblewill in cool-season turfgrass. Single applications of isoxaflutole control nimblewill more effectively than single applications of mesotrione. Nimblewill control 8 wk after initial treatment (WAIT) increased as mesotrione rates increased from 28 to 280 g ai/ha, and isoxaflutole rates increased from 28 to 168 g/ha. Isoxaflutole at 84 and 168 g/ha were the only single application treatments that controlled nimblewill greater than 80% 8 WAIT. However, sequential applications of isoxaflutole and mesotrione at 28 g/ha, 10 d apart controlled nimblewill 94 and 80%, respectively 8 WAIT. Triclopyr and fenoxaprop-p did not effectively control nimblewill and caused unacceptable turfgrass injury. Long-term control was not evaluated in these studies. However, it was concluded that isoxaflutole and mesotrione at appropriate rates and applied in sequence selectively control nimblewill without harming desirable turf.

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Long-Term Roughstalk Bluegrass Control in Creeping Bentgrass Fairways

Weed Technology ◽

10.1017/wet.2017.72 ◽

2017 ◽

Vol 31 (5) ◽

pp. 714-723

Author(s):

Sandeep S. Rana ◽

Shawn D. Askew

Keyword(s):

Creeping Bentgrass ◽

Golf Course ◽

Cool Season ◽

Putting Greens ◽

Annual Bluegrass ◽

Turf Quality ◽

Normalized Difference Vegetative Index

Methiozolin is an isoxazoline herbicide that selectively controls annual bluegrass in cool-season turf and may control roughstalk bluegrass, another weedyPoaspecies that is problematic in many turfgrass systems. However, the majority of research to date is limited to evaluating methiozolin efficacy for annual bluegrass control in creeping bentgrass putting greens. Research was conducted comparing various application regimes of methiozolin and other herbicides for long-term roughstalk bluegrass control in creeping bentgrass golf fairways. Methiozolin-only treatments did not injure creeping bentgrass or reduce normalized difference vegetative index (NDVI) at 2 golf course locations based on 20 evaluation dates over a 2.5-yr period. The 2.5-yr average turf quality generally declined as roughstalk bluegrass control increased due to transient turf cover loss. At 1 yr after last treatment, methiozolin at 1500 g ai ha-1applied four times in fall reduced roughstalk bluegrass cover 85%. This was equivalent to methiozolin at 1000 g ha-1applied four times in fall, but greater than low rates of methiozolin applied four times in spring or twice in fall and spring. Amicarbazone, primisulfuron, and bispyribac-sodium alone either did not effectively reduce roughstalk bluegrass cover, or did so at the expense of increased creeping bentgrass injury. Results of this study suggest that methiozolin alone or tank-mixed with amicarbazone or primisulfuron is an effective long-term approach for selectively controlling roughstalk bluegrass in creeping bentgrass.

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Antagonism to Plant Pathogens by Epichloë Fungal Endophytes—A Review

Plants ◽

10.3390/plants10101997 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1997

Author(s):

Stuart D. Card ◽

Daniel A. Bastías ◽

John R. Caradus

Keyword(s):

Plant Pathogens ◽

Fungal Endophytes ◽

Antimicrobial Properties ◽

Cool Season ◽

Symbiotic Associations ◽

Pathogenic Microbes ◽

Multiple Species ◽

Epichloë Endophytes ◽

Grazing Livestock

Epichloë is a genus of filamentous fungal endophytes that has co-evolved with cool-season grasses with which they form long-term, symbiotic associations. The most agriculturally important associations for pasture persistence for grazing livestock are those between asexual vertically transmitted Epichloë strains and the pasture species, perennial ryegrass, and tall fescue. The fungus confers additional traits to their host grasses including invertebrate pest deterrence and drought tolerance. Selected strains of these mutualistic endophytes have been developed into highly efficacious biocontrol products and are widely utilized within the Americas, Australia, and New Zealand for pasture persistence. Less publicized is the antagonism Epichloë endophytes display towards multiple species of saprophytic and pathogenic microbes. This opinion piece will review the current literature on antimicrobial properties exhibited by this genus of endophyte and discuss the reasons why this trait has historically remained a research curiosity rather than a trait of commercial significance.

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Soil treatment, plant species, and management effects on improved pastures on a solodic soil in the semi-arid subtropics: 3. Improving cool season plant and cattle productivity

Australian Journal of Experimental Agriculture ◽

10.1071/ea9940145 ◽

1994 ◽

Vol 34 (2) ◽

pp. 145 ◽

Cited By ~ 1

Author(s):

JS Russell

Keyword(s):

Treatment Plant ◽

Cool Season ◽

Rhodes Grass ◽

Plant Nitrogen ◽

Long Term Experiment ◽

Exchangeable Magnesium ◽

Chloris Gayana ◽

Macroptilium Atropurpureum ◽

The Cost

Seasonal analyses of grasses and legumes in a long-term experiment on a solodised solonetz soil (Natrustalf) in southern Queensland showed that the large liveweight losses of steers in the cool months (June-August) appeared to be broadly correlated with low plant nitrogen (N), phosphorus (P), and potassium (K) concentrations. Annual variation in the N, P, and K percentages of Rhodes grass (Chloris gayana) and volunteer grasses [medics (Medicago spp.) and siratro (Macroptilium atropurpureum)] as affected by soil and plant treatments were examined by fitting a Fourier series to the data. Cool season liveweight losses of steers ranged from 391 glday with sown grasses alone to 11 g/day with sown grasses and medics plus lime and gypsum. The N content of volunteer and sown grasses ranged from 0.56 to 0.70% in the cool months, which is below the accepted N requirement of 1%. The P concentration of volunteer grasses was only 0.08%, but where P fertiliser was applied, concentrations in Rhodes grass were 0.10-0.11%. Potassium levels were also low in the cool months, with values of 0.23-0.43% in grasses. Exchangeable magnesium (Mg) and sodium increased from 1.3 and 0.48 mLJ100 g at 0-10 cm depth to 8.5 and 5.2, respectively, at 40-70 cm. Exchangeable calcium decreased from 2.5 mL/100 g at 0-10 cm to 0.40 at 40-70 cm. The Mg levels in siratro (0.58-0.60%) were higher than those in Rhodes grass (mean 0.12%). Medics responded markedly to lime, resulting in a 54% increase in steer liveweight gains on Rhodes grass-medic pastures. The use of lime on solodic soils for reducing both surface soil acidity and exchangeable aluminium increased plant and steer productivity. The cost of lime transportation can be high in inland areas, but small limestone deposits have been identified on the Darling Downs and these merit closer attention.

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Establishment of Warm- and Cool-Season Native Perennial Grasses on the North-West Slopes of New South Wales. I. Dormancy and Germination

Australian Journal of Botany ◽

10.1071/bt9810111 ◽

1981 ◽

Vol 29 (2) ◽

pp. 111 ◽

Cited By ~ 31

Author(s):

GM Lodge ◽

RDB Whalley

Keyword(s):

New South ◽

Warm Season ◽

Perennial Grasses ◽

Cool Season ◽

North West ◽

The North ◽

South Wales ◽

High Germination ◽

Ecological Implications

The dormancy and germination of two groups of native perennial grasses were investigated in caryopses or dispersal units. The species were the warm-season native perennial grasses Aristida ramosa R.Br., Bothriochloa macra (Steud.) S. T . Blake. Dichanthium sericeum (R.Br.) Camus, Sporobolus elongatus R.Br., Eragrostis leptostachya Steud., Chloris truncata R.Br. and the cool-season species Stipa variabilis Hughes and Danthonia linkii Kunth. Optimum temperatures for germination were 20-35°C for A . ramosa; 15-35° for D. sericeum and C. Truncata; 20-25° for E. leptostachya; 20-30° for B. macra and S. elongatus and 15-25° for D. linkii and S . Variabilis. At 1O° and 40° D. linkii and A. ramosa respectively were the only species that had high germination percentages. Removal of the lemma and palea from freshly harvested units of A. ramosa, B. macra, D. sericeum, C. Truncata and S. variabilis significantly increased germination. In units stored at 12-27°C there was a breakdown in dormancy after 2-3 months in A. ramosa and B. macra and after 9 months in S. elongatus. In the germination of D. sericeum and D. linkii the lemma and palea appeared to have a long-term inhibitory role. Twenty-week-old whole dispersal units of B. macra, S. elongatus and E. leptostachya and 40-week-old units of S. elongatus and E. leptostachya had an obligate light requirement for germination. The ecological implications of these data in the successful germination of natural seed falls and artificial seedings are discussed.

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