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$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.
Annual spring-seeded forage crops use less water than cereal grains, including durum (Triticum turgidum L. var. durum), and may be suitable to replace summer fallow. We conducted an experiment from ...2002 through 2006 comparing yield, quality, and water and N use of durum and three annual forages, barley (Hordeum vulgare L.), barley interseeded with pea Pisum sativum L. ssp. arvense (L.) Poir., and foxtail millet Setaria italica (L.) Beauv. in 2-yr rotations. Durum in rotation with summer fallow and alfalfa (Medicago sativa L.) were included. Averaged over 5 yr, alfalfa had higher forage yield and quality, water use, and N accumulation compared to annual forages. Annual forages had similar preplant and postharvest soil water contents, but barley and barley–pea had higher yields and water use compared to millet. Barley–pea intercrop had superior forage crude protein (CP), neutral detergent fiber (NDF) and N accumulation compared to barley and millet, but acid detergent fiber (ADF) and nitrogen recovery index (NRI) were similar among annual forages. Averaged over 4 yr, preplant soil water and residual N content were greater for durum following fallow than for durum following annual forages, resulting in reduced fertilizer N requirement and greater yield, water use, grain N accumulation and NRI following fallow. Replacing summer fallow with annual forages reduced durum grain yield by 727 kg ha–1 but provided forage yield of 4.9 Mg ha–1. Annualized net returns in annual forage-durum systems were $127 ha–1, $77 and $34 ha–1 greater than for fallow-durum and alfalfa, respectively. Replacing summer fallow with annual forages reduced durum yield but improved profitability.
A rise in the incidence of mosquito-transmitted Cache Valley virus (CVV) in lambs in 2011 prompted a study to evaluate on-animal pyrethroid insecticides to reduce mosquito attacks on sheep. Using ...enclosure traps for 1 night per wk for 6 wk, we compared engorgement rates of mosquitoes given the opportunity to feed on untreated sheep and sheep treated with 1 Python® insecticide ear tag (containing 10% zeta-cypermethrin and 20% piperonyl butoxide) per animal or 2 synergized permethrin body spray treatments (containing 2.5% permethrin and 2.5% piperonyl butoxide). During the 6-wk study, 18,920 mosquitoes were collected in the animal-baited enclosure traps. Thirteen species were identified from these collections with the floodwater species Aedes increpitus and Ae. idahoensis making up 68% of the total. Potential CVV vector species, making up 25% of the samples, included Ae. vexans, Ae. dorsalis, Culex tarsalis, and Culiseta inornata. Traps baited with untreated sheep collected 9,701 mosquitoes with 65% of these engorged. Traps baited with sheep treated with Python ear tags or permethrin spray collected 4,034 and 4,555, respectively, with engorgement rates of 23% and 35%. Blood feeding on ear-tagged sheep was significantly reduced by as much as 90% compared to the untreated sheep, and protection lasted 4 wk or longer. Permethrin spray treatments were most effective within 24 h after application and provided better protection against Ae. dorsalis than the Python tag. Effectiveness of the permethrin spray diminished 1 wk after the 2nd application was made. The effect of these treatments appeared to be repellency because negligible mosquito mortality was observed at the time of collection. Further evaluation of these insecticides under conditions of natural exposure to a mosquito-borne pathogen is warranted.
In dryland farming areas of Montana, annual precipitation is not sufficient for annual planting of cereal grains. Instead, a crop-summer fallow farming system is used to conserve soil moisture and ...increase available nitrogen for subsequent crop growth. Managing this summer fallow, either by mechanical means or with herbicides, is the highest variable cost associated with dryland grain production in Montana. Wheat stem sawfly,
Cephus cinctus (Hymenoptera: Cephidae) is the most damaging insect pest to Montana's US$ 1 billion per year grain industry. Weed management is the largest variable cost associated with dryland grain production and summer fallow management. Six fields, located on four commercial Montana grain operations, were grazed by sheep and goats from October 2002 to May 2003 to determine the impact grazing has on
C. cinctus populations, weed and volunteer cereal growth, soil compaction, and gravimetric water concentrations. Percent
C. cinctus larval mortality and percent reduction of weed biomass was greater in grazed compared to non-grazed areas (
P
≤
0.01). No differences in soil bulk density or gravimetric water concentrations were found between treatments (
P
>
0.11). Grazing fallow with sheep and goats appears to successfully improve
C. cinctus and weed management in grain production systems without impacting soil compaction.
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 Simpson's 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).
To describe the process and outcomes of using a new evidence base to develop scientific guidelines that specify the type and minimum dose of exercise necessary to improve fitness and cardiometabolic ...health in adults with spinal cord injury (SCI).
International.
Using Appraisal of Guidelines, Research and Evaluation (AGREE) II reporting criteria, steps included (a) determining the guidelines' scope; (b) conducting a systematic review of relevant literature; (c) holding three consensus panel meetings (European, Canadian and International) to formulate the guidelines; (d) obtaining stakeholder feedback; and (e) process evaluation by an AGREE II consultant. Stakeholders were actively involved in steps (c) and (d).
For cardiorespiratory fitness and muscle strength benefits, adults with a SCI should engage in at least 20 min of moderate to vigorous intensity aerobic exercise 2 times per week AND 3 sets of strength exercises for each major functioning muscle group, at a moderate to vigorous intensity, 2 times per week (strong recommendation). For cardiometabolic health benefits, adults with a SCI are suggested to engage in at least 30 min of moderate to vigorous intensity aerobic exercise 3 times per week (conditional recommendation).
Through a systematic, rigorous, and participatory process involving international scientists and stakeholders, a new exercise guideline was formulated for cardiometabolic health benefits. A previously published SCI guideline was endorsed for achieving fitness benefits. These guidelines represent an important step toward international harmonization of exercise guidelines for adults with SCI, and a foundation for developing exercise policies and programs for people with SCI around the world.
The purpose of this study was to examine the propulsion asymmetries of wheelchair athletes while sprinting on an instrumented, dual‐roller ergometer system. Eighteen experienced wheelchair rugby ...players (8 low point (LP) (class ≤1.5) and 10 high point (HP) (class ≥2.0)) performed a 15‐second sprint in their sports wheelchair on the instrumented ergometer. Asymmetry was defined as the difference in distance and power output (PO) between left and right sides when the best side reached 28 m. Propulsion techniques were quantified based on torque and velocity data. HP players covered an average 3 m further than the LP players (P = .002) and achieved faster sprint times than LP players (6.95 ± 0.89 vs 8.03 ± 0.68 seconds, P = .005) and at the time the best player finished (5.96 seconds). Higher peak POs (667 ± 108 vs 357 ± 78 W, P = .0001) and greater peak speeds that were also evident were for HP players (4.80 ± 0.71 vs 4.09 ± 0.45 m/s, P = .011). Greater asymmetries were found in HP players for distance (1.86 ± 1.43 vs 0.70 ± 0.65 m, P = .016), absolute peak PO (P = .049), and speed (0.35 ± 0.25 vs 0.11 ± 0.10 m/s, P = .009). Although HP players had faster sprint times over 28 m (achieved by a higher PO), high standard deviations show the heterogeneity within the two groups (eg, some LP players were better than HP players). Quantification of asymmetries is important not only for classifiers but also for sports practitioners wishing to improve performance as they could be addressed through training and/or wheelchair configuration.
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 ...infestation potential of currently grown spring durum cultivars. Field trials were conducted in 1998 and 1999 to determine wheat stem sawfly susceptibility of 13 spring durum cultivars and one hard red spring wheat. Preharvest infestations ranged from 2-55%. Postharvest larval infestations of stubble ranged from 1-9.5%. Three durum cultivars 'Lloyd', 'Plenty', and 'Sceptre' appear to offer potential, as a rotational crop, for management of wheat stem sawfly.
Abstract The aim of the current investigation was to explore the lateral stiffness of different sports wheelchair wheels available to athletes in ‘new’ and ‘used’ conditions and to determine the ...effect of (a) stiffness, (b) tyre type (clincher vs. tubular) and (c) tyre orientation on the physiological and biomechanical responses to submaximal and maximal effort propulsion specific to wheelchair basketball. Eight able-bodied individuals participated in the laboratory-based testing, which took place on a wheelchair ergometer at two fixed speeds (1.1 and 2.2 m s−1 ). Outcome measures were power output and physiological demand (oxygen uptake and heart rate). Three participants with experience of over-ground sports wheelchair propulsion also performed 2 × 20 m sprints in each wheel configuration. Results revealed that wheels differed significantly in lateral stiffness with the ‘new’ Spinergy wheel shown to be the stiffest (678.2 ± 102.1 N mm−1 ). However the effects of stiffness on physiological demand were minimal compared to tyre type whereby tubular tyres significantly reduced the rolling resistance and power output in relation to clincher tyres. Therefore tyre type (and subsequently inflation pressure) remains the most important aspect of wheel specification for athletes to consider and monitor when configuring a sports wheelchair.
Changes in soil bulk density and soil nutrient profiles are a major concern of dryland grain producers considering grazing sheep on cereal stubble fields. Our objective was to compare burned, grazed, ...tilled, trampled and clipped wheat stubble fields on changes in soil bulk density and soil nutrient profiles. Treatments were evaluated in a series of three experiments using a randomized complete block design and four replications at each site. Contrast statements were used to make pre-planned comparisons among treatments. For Experiment 1, treatments were fall tilled, fall grazed, spring grazed, fall and spring combined (Fall/Spr) grazed, and an untreated control. Five mature ewes were confined with electric fence to a 111 m2 plot for 24 h for fall and spring grazed plots resulting in a stocking rate of 452 sheeps d/ha. For Fall/Spr, the stocking rate was 904 sheeps d/ha. For Experiment 2, treatments were fall grazed, fall burned, fall tilled, and an untreated control. In Experiment 3, treatments were fall trampling by sheep, spring trampling by sheep, fall and spring combined (Fall/Spr) trampling by sheep, hand clipping to a stubble height of 4.5 cm, and an untreated control. Trampling treatments were done at the same stocking rates as grazing treatments but sheep were muzzled to prevent intake. In Experiment 1, post-treatment organic matter tended to be greater (P = 0.09) in the mean of the grazed treatments than control plots. In all of the experiments, change in soil bulk density, and soil nutrient profiles did not consistently differ (P > 0.07) among treatments in any manner that would suggest a detrimental impact of grazing sheep on small grain residue. These results indicate a strong potential for grazing sheep on grain stubble without adversely impacting soil bulk density or nutrient profiles.
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