Hayes B. Goosey

Evaluation of Alfalfa Weevil (Coleoptera: Curculionidae) Densities and Regrowth Characteristics of Alfalfa Grazed by Sheep in Winter and Spring

Fall regrowth of alfalfa, Medicago sativa (L.), serves as a major source of winter pasture for Montana sheep producers. In years of drought, alfalfa fields are extensively winter/spring grazed; how...

Durum Spring Wheat Susceptibility to Wheat Stem Sawfly (Hymenoptera: Cephidae)

The wheat stem sawfly, Cephus cinctus Norton, is the primary arthropod pest of wheat, Triticum aestivum Thell, in the Northern Great Plains. Yet, information is unavailable on wheat stem sawfly inf...

A Degree-Day Model of Sheep Grazing Influence on Alfalfa Weevil and Crop Characteristics

ABSTRACT Domestic sheep (Ovis spp.) grazing is emerging as an integrated pest management tactic for alfalfa weevil, Hypera postica (Gyllenhal), management and a degree-day model is needed as a decision and support tool. In response to this need, grazing exclosures with unique degree-days and stocking rates were established at weekly intervals in a central Montana alfalfa field during 2008 and 2009. Analyses indicate that increased stocking rates and grazing degree-days were associated with decreased crop levels of weevil larvae. Larval data collected from grazing treatments were regressed against on-site and near-site temperatures that produced the same accuracy. The near-site model was chosen to encourage producer acceptance. The regression slope differed from zero, had an r2of 0.83, and a root mean square error of 0.2. Crop data were collected to achieve optimal weevil management with forage quality and yield. Differences were recorded in crude protein, acid and neutral detergent fibers, total digestible nutrients, and mean stage by weight. Stem heights differed with higher stocking rates and degree-days recording the shortest alfalfa canopy height at harvest. The degree-day model was validated at four sites during 2010 with a mean square prediction error of 0.74. The recommendation from this research is to stock alfalfa fields in the spring before 63 DD with rates between 251 and 583 sheep days per hectare (d/ha). Sheep should be allowed to graze to a minimum of 106 and maximum of 150 DD before removal. This model gives field entomologists a new method for implementing grazing in an integrated pest management program.

Influence of tillage system, oilseed species, and insecticidal seed treatment on flea beetle (Coleoptera: Chrysomelidae) damage, oilseed production, and postharvest residue cover.

The influence of tillage system and imidacloprid seed treatment on flea beetle (Phyllotreta cruciferae (Goeze)) damage, oilseed production, volunteer barley density, and post harvest residue cover was determined for Polish canola (Brassica rapa L.) and yellow mustard (Sinapis alba L.). Field trials were conducted at Moccasin, MT, USA, from 1998 through 2000. Flea beetle damage was assessed on cotyledon and first true leaf stage plants using a numerical damage rating. Flea beetle damage was low in both tillage systems and on both plant species when imidacloprid seed treatment was applied. In the absence of seed treatment, seedlings of both plant species in conventionally tilled plots usually suffered more damage than did seedlings in zero tillage plots. Canola often sustained more damage than yellow mustard. Across tillage system and insecticidal seed treatment, yellow mustard produced significantly greater (P> 0.01) seed yields than canola. Density of volunteer barley was significantly greater (P > 0.01) ...

Integration of sheep grazing for cover crop termination into market gardens: Agronomic consequences of an ecologically based management strategy

Cover crops are suites of non-marketable plants grown to improve soil tilth and reduce erosion. Despite these agronomic benefits, the use of cover crops is often limited because they do not provide a direct source of revenue for producers. Integrating livestock to graze cover crops could provide both an expeditious method for cover crop termination and an alternative source of revenue. However, there has been little research on the agronomic impacts of grazing for cover crop termination, especially in horticultural market-gardens. We conducted a 3-year study comparing the effects of sheep grazing to terminate a four species cover crop (buckwheat, sweetclover, peas and beets) with those of mowing on soil quality indicators, cover crop termination efficacy, and subsequent cash-crop yields. In addition, we tested the nutritional quality of the cover crop as forage. Comparedwith mowing, sheep grazing did not affect soil chemistry, temperature or moisture. Our study demonstrates that sheep grazing removed more cover crop biomass than mowing at termination. The assessment of nutritional indices suggests that the four-species cover crop mixture could provide high-quality forage with a potential value of US

Impacts of Contrasting Alfalfa Production Systems on the Drivers of Carabid Beetle (Coleoptera: Carabidae) Community Dynamics.

144.00–481.80 ha of direct revenue as a grazing lease. Cash-crop yields did not differ between previously grazed and previously mowed plots in the subsequent growing season. We conclude that integrating sheep grazing into market vegetable garden operations could make cover crops more economically viable without having adverse effects on subsequent cash crops.

Hymenoptera Parasitoid Response to Sheep Grazing, Tillage, and Herbicides in Wheat-Fallow Rotations

ABSTRACT Growing concerns about the environmental consequences of chemically based pest control strategies have precipitated a call for the development of integrated, ecologically based pest management programs. Carabid or ground beetles (Coleoptera:Carabidae) are an important group of natural enemies of common agricultural pests such as aphids, slugs, and other beetles. Alfalfa (Medicago sativa L.) is one of the most common forage crop species in the semi-arid western United States. In 2011, Montana alone produced 4.0 × 106 Mg of alfalfa on 8.1 × 105 ha for gross revenue in excess of US

Arthropod Abundance Associated with the Natural Resources Conservation Service: Implications for Greater Sage-Grouse Management.

4.3 × 108,making it the third largest crop by revenue. We conducted our study over the 2012 and 2013 growing seasons. Each year, our study consisted of three sites each with adjacent systems of monoculture alfalfa, alfalfa nurse cropped with hay barley, and an uncultivated refuge consisting of a variety of forbs and grasses. Carabid community structure differed and strong temporal shifts were detected during both 2012 and 2013.Multivariate fuzzy set ordination suggests that variation in canopy height among the three vegetation systems was primarily responsible for the differences observed in carabid community structure. Land managers may be able to enhance carabid species richness and total abundance by creating a heterogeneous vegetation structure, and nurse cropping in particular may be effective strategy to achieve this goal.

Evaluation of Mosquito Responses to Pyrethroid Insecticides Topically Applied to Sheep

Abstract Sweep net sampling of spring and winter wheat (Triticum spp.) was conducted in 2007 and 2008 at the Fort Ellis Research and Extension Center, Montana State University, Bozeman, MT to determine hymenoptera parasitoid family composition, abundance, and diversity in two wheat-fallow cropping systems managed by either tillage, herbicides, or domestic sheep (Ovis aries) grazing. Eleven hymenopteran families classified as parasitoids were captured in 2007 and 16 families in 2008. The mean abundance of parasitoids was greatest (P ≤ 0.05) in crops where the fallow component of the rotation was managed with sheep grazing, as opposed to tillage and herbicide systems. Family diversity, as indexed by Simpsons D, did not differ between fallow management treatments (P  =  0.88) or cropping system (P  =  0.74) but did differ between study year (P ≤ 0.01).

Incorporating sheep into dryland grain production systems I. Impact on over-wintering larva populations of wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae)

One goal of the Natural Resource Conservation Service’s Sage-Grouse Initiative was to reverse the western US trend of declining sage-grouse populations. The sage-grouse initiative aims at preventing ‘sod-busting’ activities (conversion of native habitats into cropland) which is identified as the largest threat to stable sage-grouse populations and their habitats (USFWS 2010). Rest-rotation livestock grazing is implemented on sage-grouse ‘core areas’ with the purpose of improving rangeland health on private lands and eliminate the need of listing sage-grouse on the threatened or endangered species list. We collected arthropods in central Montana from three habitat classes associated with the Sage-grouse Initiative: 1) Grazed (actively grazed livestock pastures), 2) Deferred (Ungrazed pastures), and 3) Idle (Lands of the Lake Mason National Wildlife Refuge lower unit) and report here on 2012-2014 findings. Total arthropod catches in pitfall traps were greatest from livestock Idle pastures; however, greater numbers of those arthropods classified as sage-grouse food were caught from Deferred pastures. Differences in habitat class catches revolved primarily around the high levels of thatch found on the Lake Mason Wildlife Refuge which altered the community composition and predator:prey ratios.