CASE STUDY: Effects of interseeding date of cool-season annual grasses and preplant glyphosate application onto a warm-season grass sod on forage production, forage nutritive value, performance of stocker cattle, and net return1

The objective of this study was to compare the forage nutritive value of cool-season perennial grasses and legumes with that of warm-season annual grasses grazed by organic dairy cows. Two pasture systems were analyzed across the grazing season at an organic dairy in Morris, Minnesota. Pasture system 1 included perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata L.), meadow bromegrass (Bromus riparius Rehmann), meadow fescue (Schedonorus pratensis (Huds.) P. Beauv), alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), red clover (Trifolium pratense L.), and chicory (Cichorium intybus L.). Pasture system 2 was a combination of system 1 and monocultures of warm-season grasses (sorghum-sudangrass (Sorghum bicolor [L.] Moench subsp. drummondii [Steud.]) and teff (Eragrostis tef L.)). Across the grazing season, forage yield was 39% greater for system 2 than system 1 due to greater forage yield during the summer. Neutral detergent fiber (NDF) and acid detergent fiber (ADF) were similar for cool-season and warm-season grasses. Warm-season grasses had greater forage yield during the summer months compared with cool-season grasses and legumes. The total tract NDF digestibility (TTNDFD) varied by month and year across the study for both pasture systems. Overall, weather may affect the forage nutritive value for both cool-season perennial grasses and legumes and warm-season annual grasses.

Download Full-text

115 Nitrogen fertilizer effects on above ground sward characteristics and beef heifer performance from native warm-season grass blends

Journal of Animal Science ◽

10.1093/jas/skz397.060 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 26-27

Author(s):

Caroline Chappell ◽

Landon Marks ◽

Katie Mason ◽

Mary K Mullenix ◽

Sandra L Dillard ◽

...

Keyword(s):

Nutritive Value ◽

Warm Season ◽

Ground Cover ◽

Application Rate ◽

Light Interception ◽

Botanical Composition ◽

Forage Production ◽

Beef Heifers ◽

Fertilizer Application Rate ◽

Canopy Light Interception

Abstract A 2-yr study was conducted at Black Belt Research and Extension Center in Marion Junction, AL, to evaluate the effect of nitrogen (N) fertilizer application rate on forage production characteristics, nutritive value, and animal performance of beef heifers grazing a mixture of native warm-season grasses (NWSG) including big bluestem, little bluestem, and indiangrass. Six, two-hectare plots were randomly assigned to one of two treatments (0 or 67 kg N ha-1 applied in early April; n = 3 replications per treatment). Paddocks were continuously stocked with four weaned Angus × Simmental beef heifers (initial BW 288 ± 7 kg) from late May/early June through mid-to-late August during 2018 (73 grazing d) and 2019 (70 grazing d), respectively. Put-and-take cattle were used to manage forage to a target of 38 cm. Forage mass and canopy heights were collected every two weeks during the trial. Visual ground cover ratings, canopy light interception, and botanical composition were measured at the beginning and end of the trial in each year. Hand-plucked samples were collected every two weeks during the grazing trial to determine forage nutritional value. Data were analyzed using the PROC MIXED procedure in SAS 9.4, and differences were declared significant when P ≤ 0.05. Nitrogen fertilized NWSG had greater crude protein (P < 0.0001), sward heights (P = 0.0003), and canopy light interception at the beginning of the season (P = 0.0049) compared to non-fertilized paddocks. However, there were no differences (P ≥ 0.05) among N-fertility treatments for mean forage mass, heifer ADG, or BCS across the 2-yr study. Botanical composition data indicated that indiangrass decreased from 64% to 61% (P = 0.0022) and weed pressure increased from 11% to 15% (P = 0.0064) across the summer grazing season. Canopy light interception decreased by 51% from early June to August in fertilized NWSG and 26% in unfertilized paddocks, respectively. These data illustrate that NWSG systems may provide a viable grazing system in the summer months under reduced N inputs.

Download Full-text

Milk Production, Body Weight, Body Condition Score, Activity, and Rumination of Organic Dairy Cattle Grazing Two Different Pasture Systems Incorporating Cool- and Warm-Season Forages

Animals ◽

10.3390/ani11020264 ◽

2021 ◽

Vol 11 (2) ◽

pp. 264

Author(s):

Kathryn E. Ritz ◽

Bradley J. Heins ◽

Roger D. Moon ◽

Craig C. Sheaffer ◽

Sharon L. Weyers

Keyword(s):

Body Weight ◽

Milk Production ◽

Body Condition Score ◽

Warm Season ◽

Cool Season ◽

Organic Dairy ◽

Condition Score ◽

Annual Grasses ◽

System 2 ◽

System 1

Organic dairy cows were used to evaluate the effect of two organic pasture production systems (temperate grass species and warm-season annual grasses and cool-season annuals compared with temperate grasses only) across two grazing seasons (May to October of 2014 and 2015) on milk production, milk components (fat, protein, milk urea nitrogen (MUN), somatic cell score (SCS)), body weight, body condition score (BCS), and activity and rumination (min/day). Cows were assigned to two pasture systems across the grazing season at an organic research dairy in Morris, Minnesota. Pasture System 1 was cool-season perennials (CSP) and Pasture System 2 was a combination of System 1 and warm-season grasses and cool-season annuals. System 1 and System 2 cows had similar milk production (14.7 and 14.8 kg d−1), fat percentage (3.92% vs. 3.80%), protein percentage (3.21% vs. 3.17%), MUN (12.5 and 11.5 mg dL−1), and SCS (4.05 and 4.07), respectively. Cows in System 1 had greater daily rumination (530 min/day) compared to cows in System 2 (470 min/day). In summary, warm-season annual grasses may be incorporated into grazing systems for pastured dairy cattle.

Download Full-text

Herbicides for Postemergence Control of Annual Grass Weeds in Seedling Forage Grasses

Weed Science ◽

10.1017/s0043174500072088 ◽

1989 ◽

Vol 37 (3) ◽

pp. 375-379 ◽

Cited By ~ 12

Author(s):

Thomas J. Peters ◽

Russell S. Moomaw ◽

Alex R. Martin

Keyword(s):

Warm Season ◽

Big Bluestem ◽

Forage Grasses ◽

Annual Grass ◽

Cool Season ◽

Intermediate Wheatgrass ◽

Green Foxtail ◽

Annual Grasses ◽

Large Crabgrass ◽

Warm Season Grasses

The control of three summer annual grass weeds with herbicides during establishment of forage grasses was studied near Concord and Mead, NE, in 1984, 1985, and 1986. Three cool-season forage grasses, intermediate wheatgrass, tall fescue, and smooth bromegrass, and two warm-season grasses, big bluestem and switchgrass, were included. The control of three major summer annual grasses, green foxtail, barnyardgrass, and large crabgrass, was excellent with fenoxaprop at 0.22 kg ai/ha. Slight to moderate injury to cool-season forage grasses and severe injury to warm-season grasses were evident. Sethoxydim at 0.22 kg ai/ha and haloxyfop at 0.11 kg ai/ha controlled green foxtail and large crabgrass, but not barnyardgrass. Sulfometuron-treated big bluestem and switchgrass plots had the best forage stand frequencies and yields and, at the rate used, sulfometuron satisfactorily controlled green foxtail but only marginally controlled barnyardgrass and large crabgrass.

Download Full-text

Yield, Yield Distribution, and Nutritive Value of Intensively Managed Warm-Season Annual Grasses

Agronomy Journal ◽

10.2134/agronj2001.1257 ◽

2001 ◽

Vol 93 (6) ◽

pp. 1257-1262 ◽

Cited By ~ 22

Author(s):

Renato S. Fontaneli ◽

Lynn E. Sollenberger ◽

Charles R. Staples

Keyword(s):

Nutritive Value ◽

Warm Season ◽

Yield Distribution ◽

Annual Grasses ◽

Intensively Managed

Download Full-text

76 Evaluating Nitrogen Management Strategies to Improve Southern Bermudagrass Grazing Systems

Journal of Animal Science ◽

10.1093/jas/skz397.059 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 26-26

Author(s):

Justin C Burt ◽

Jennifer J Tucker ◽

Lisa Baxter

Keyword(s):

Nutritive Value ◽

Cynodon Dactylon ◽

Management Strategies ◽

Stocking Density ◽

Warm Season ◽

The South ◽

Forage Crops ◽

University Of Georgia ◽

Annual Grasses ◽

The University

Abstract Bermudagrass (Cynodon dactylon) is one of the most common perennial warm-season forage crops grown in the South. While prominent in the region bermudagrass management requires large amounts of fertility and forage quality is moderate at best. Incorporating a legume into bermudagrass pastures could serve as an alternative to the necessary applications of synthetic N, while also improving the nutritive value of the forage base. A two-year grazing evaluation was conducted from May-Sept. 2018 (Y1) and May-Aug. 2019 (Y2) at the University of Georgia Tifton Campus in Tifton, Georgia, to compare concurring production of alfalfa/bermudagrass mixed pastures (BGA) with bermudagrass monoculture pastures with (BGN) or without (BGZ) the application of synthetic nitrogen. The experimental design was a randomized complete block with three treatments and two replications. All paddocks were evaluated pre and post grazing event for herbage availability, botanical composition, forage species competitiveness, and nutritive value. Paddocks (0.8-ha) were rotationally grazed using put and take management with stocker steers (Y1 BW=195.9±22.9 kg; Y2 BW=228.5±30.0 kg), two testers per treatment. Steers were weighed at initiation, conclusion, and on a 28–30 day interval for calculation of ADG and gain/ha. Statistical analysis was conducted using the PROC MIXED procedure of SAS. Despite significant drought in Y2, year did not affect total gain/ha, however treatment did (P = 0.04), such that BGA was highest (383.6±35.1 kg/ha), and BGN and BGZ were not different (261.2±35.1 kg/ha and 239.0±35.1 kg/ha, respectively). This is likely due to the lower stocking density and inclusion of high-quality volunteer annual grasses in BGZ treatments which allowed for selective grazing. These data suggest that rotationally grazing alfalfa/bermudagrass mixtures can result in a higher gain/ha, than bermudagrass pastures that are supplemented with or without synthetic N in the South.

Download Full-text

Seasonal, Regional, and Storm-Scale Variability of Cloud-to-Ground Lightning Characteristics in Florida

Monthly Weather Review ◽

10.1175/2010mwr3585.1 ◽

2011 ◽

Vol 139 (6) ◽

pp. 1826-1843 ◽

Cited By ~ 24

Author(s):

Scott D. Rudlosky ◽

Henry E. Fuelberg

Keyword(s):

Structural Damage ◽

Warm Season ◽

Atmospheric Conditions ◽

Cool Season ◽

Peak Current ◽

Close Proximity ◽

Cloud To Ground Lightning ◽

Large Peak ◽

Reversed Polarity

Abstract Seasonal, regional, and storm-scale variations of cloud-to-ground (CG) lightning characteristics in Florida are presented. Strong positive CG (+CG) and negative CG (−CG) flashes (i.e., having large peak current) are emphasized since they often are associated with strong storms, structural damage, and wildfire ignitions. Although strong −CG flashes are most common during the warm season (May–September) over the peninsula, the greatest proportion of strong +CG flashes occurs during the cool season (October–April) over the panhandle. The warm season exhibits the smallest +CG percentage but contains the greatest +CG flash densities, due in part to more ambiguous +CG reports (15–20 kA). The more frequent occurrence of ambiguous +CG reports helps explain the unusually small average +CG peak current during the warm season, whereas strong +CG reports (>20 kA) appear to be responsible for the greater average warm season +CG multiplicity. The −CG flash density, multiplicity, and peak current appear to be directly related, exhibiting their greatest values during the warm season when deep storms are most common. A case study examines the atmospheric conditions and storm-scale processes associated with two distinct groups of storms on 13–14 May 2007. Although these groups of storms form in close proximity, several factors combine to produce predominately strong +CG and −CG flashes in the northern (south Georgia) and southern (north Florida) regions, respectively. Results suggest that heat and smoke very near preexisting wildfires are key ingredients in producing reversed-polarity (+CG dominated) storms that often ignite subsequent wildfires.

Download Full-text

Ecological and Control Studies of Musk Thistle

Weed Science ◽

10.1017/s004317450003037x ◽

1968 ◽

Vol 16 (1) ◽

pp. 1-4 ◽

Cited By ~ 18

Author(s):

Israel Feldman ◽

M. K. McCarty ◽

C. J. Scifres

Keyword(s):

Warm Season ◽

Dichlorophenoxyacetic Acid ◽

Cool Season ◽

Carduus Nutans ◽

Warm Season Grass ◽

Excellent Control ◽

2,4 Dichlorophenoxyacetic Acid ◽

And Control ◽

Cool Season Grass ◽

Thistle Plant

Herbicides applied April 30, May 10, or October 14 gave best control of musk thistle (Carduus nutansL.). The most effective herbicide at all dates and rates was 4-amino-3,5,6-trichloropicolinic acid (picloram). Two lb/A of 2-methoxy-3,6-dichlorobenzoic acid (dicamba) also was effective at all spring dates. Two lb/A of 2,4-dichlorophenoxyacetic acid (2,4-D) resulted in excellent control of musk thistle when applied May 10 or October 14.More musk thistle seedlings became established in nongrazed, cool season grass pastures than in nongrazed, mixed warm season grass pastures. Greater germination was attributed to the reserve moisture and accumulation of litter which served as an excellent germination medium. However, only one musk thistle plant remained in the nongrazed pastures 1 year after seeding. The remainder of the seedlings and young rosettes found in the protected areas in 1965 had succumbed to the heavy competition by 1966.

Download Full-text

Harvest Frequency and Native Warm-Season Grass Species Influence Nutritive Value

cftm ◽

10.2134/cftm2019.04.0030 ◽

2019 ◽

Vol 5 (1) ◽

pp. 190030

Author(s):

J. Brett Rushing ◽

Rocky W. Lemus ◽

Johnson C. Lyles

Keyword(s):

Nutritive Value ◽

Warm Season ◽

Grass Species ◽

Harvest Frequency ◽

Warm Season Grass

Download Full-text

Micronutrients Considerations for Warm-Season Grass Systems in Florida

EDIS ◽

10.32473/edis-ag419-2017 ◽

2017 ◽

Vol 2017 (6) ◽

Author(s):

Jane C. Griffin ◽

Joao Mauricio Buen Vendramini ◽

Diane L. Rowland ◽

Maria Lucia Silveira

Keyword(s):

Plant Growth ◽

Production Systems ◽

Warm Season ◽

Ground Cover ◽

Essential Elements ◽

Forage Production ◽

Warm Season Grass ◽

And Performance ◽

Warm Season Grasses

Warm-season grasses are vital to livestock production systems and dominate ground cover in tropical and subtropical areas. Many popular warm-season grasses, such as bahiagrass and bermudagrass, have roots that penetrate deeper into the soil profile, which aids in both drought tolerance, nutrient uptake, and the minimization of soil erosion. In Florida, spodosols are the predominant soil order used for forage production and have limited fertility. Micronutrients are essential elements that are required in smaller quantities than macronutrients but are equally as important for proper plant growth and performance. An element can be considered essential for plant growth if a plant fails to complete its life cycle in the absence of the element, the elements action is specific and cannot be completely replaced by another element, it has a direct effect on the organism, or it is a constituent of a molecule that is known to be essential. The objective of this publication is to describe the role of micronutrients in warm-season grass production.

Download Full-text