A study was conducted on foothills rangeland to determine whether grazing patterns differed among cow breeds and to determine whether there was a relationship between individual grazing patterns and performance of beef cows. Hereford (HH), Tarentaise (TT), 3/4 Hereford x 1/4 Tarentaise (3H1T), 1/2 Hereford x 1/2 Tarentaise (HT), and 1/4 Hereford x 3/4 Tarentaise (1H3T) cows were observed during the summers of 1997 (n = 183) and 1998 (n = 159). Locations of individual cows were recorded two to three times per week during 1.5- to 2.5-h periods in the morning by observers on horseback. Statistical models included cow breed, age, and nursing status. Data from each year were analyzed separately. During 1997 and 1998, nonlactating cows were located at greater (P < 0.05) vertical distances from water than lactating cows. In 1998, nonlactating cows used steeper (P < 0.05) slopes than lactating cows. However, nonlactating cows did not travel as far horizontally from water (P < 0.05) as lactating cows in 1997. Younger cows (3 yr) traveled further (P < 0.05) from water both vertically and horizontally than older cows (5+ yr) in 1997, but not during 1998. Tarentaise and 1H3T cows were observed at greater (P < 0.05) vertical distances from water than HH cows during both years of the study. During 1998, TT and 1H3T cows used steeper (P < 0.05) slopes than HH cows. Using residual correlations, there were no consistent relationships between topographic aspects of individual grazing locations and cow weight, height, and body condition score. In 1997, cows with earlier calving dates and correspondingly heavier calf weaning weights used areas that had greater vertical distances to water; however, in 1998 there were no relationships (P > 0.05) of calving date and weaning weight with cow location. During both years, pregnant and nonpregnant cows used terrain similarly (P > 0.05), which suggests that cow reproductive performance was not related to terrain use. Grazing patterns in foothills rangeland varied among cow breeds. Performance of cows that used more rugged topography was similar to cows using gentler terrain.

Four ruminally and abomasally cannulated steers were used to evaluate the effects of barely variety on rate, site, and extent of digestion of high-concentrate diets. The treatments compared were 1) corn, 2) Gunhilde barley (GUN), Harrington barley (HAR), and 4) Medallion barley (MED). Diets were balanced to be isocaloric and isonitrogenous. Ruminal OM digestion was greater (P = .04) in steers fed corn than in those fed GUN, HAR, and MED (61.9 vs average 53.7%). No differences (P > .10) were seen in ruminal starch digestion (average 92.8%) or in starch flow to the abomasum (average 199 g/d) between diets. Total tract digestion of starch was greater (P = .09) in steers fed barley than in those fed corn (average 98.6 vs 95.7%). Total and nonammonia N presented to the abomasum were greater (P < .05) for steers fed HAR and GUN than for those fed MED and corn. Microbial N flow was lowest (P = .01) in corn-fed steers, highest in steers fed GUN and HAR, and intermediate in steers fed MED. Microbial efficiency was 59% greater (P = .03) in steers fed barley than in steers consuming corn. Ruminal acetate: propionate was lower (P = .002) in steers fed corn and HAR than in those fed GUN and MED. Compared to GUN, HAR, and MED barleys, corn had a lower (P < .03) rate (-.11 vs average -.47) and extent (15 h; 70.3 vs average 98.1%) of in situ starch disappearance. Differences in digestive characteristics found between barley varieties may contribute to differences in animal performance.

Eighty Angus x Hereford steers (average initial weight 287 kg) were used in a 168-d finishing study to evaluate the effects of barley variety on feedlot performance, diet digestion, and carcass characteristics. The four treatments compared in this completely randomized design (four pens/ treatment) were high-concentrate diets based on 1) corn, 2) Gunhilde barley (GUN), 3) Harrington barley (HAR), or 4) Medallion barley (MED). Steers consuming corn gained 10% faster (P < .01) than steers fed HAR, and HAR resulted in 8% faster (P < .01) gains than GUN or MED. Dry matter intake was greater (P < .01) for steers fed corn than for steers fed GUN, HAR, or MED, and HAR-fed steers consumed more than MED-fed steers. Efficiency (kilograms of gain/100 kg of feed) was higher (P < .05) for steers fed GUN, HAR, and MED than for corn-fed steers. Estimated NEm and NEg of barley varieties ranged from 2.32 to 2.51 Mcal of NEm/kg and 1.61 and 1.77 Mcal of NEg/kg. Carcass weight was greater (P < .01) for steers fed corn rather than HAR and greater (P < .01) for HAR-fed steers than for those fed GUN or MED. Quality grade was higher (P < .05) for HAR-fed steers than for steers fed corn, GUN, or MED. Steers fed corn had the highest (P < .01) digestible starch intake, followed by steers fed HAR, GUN, and, finally, MED, the same approximate ranking as for ADG. A diet based on Harrington barley resulted in greater DMI, ADG, and carcass quality grade compared with diets based on Gunhilde or Medallion barleys.

Wheat (Triticum spp.) dominates dryland grain crop production in the North American Great Plains and other regions with semi‐arid steppe climates. A common practice is to alternate winter or spring wheat with a 14‐ to 21‐mo fallow period to allow for soil‐water recharge, despite economic inefficiencies and environmental degradation. Replacing fallow with non‐cereal grain and seed crops often reduces future wheat yields due to increased water stress during grain fill. The use of annual forages may not have the disadvantages associated with grain and seed crops. The objective of this review was to determine benefits and challenges of incorporating annual forages into dryland wheat systems in semi‐arid steppe climates, using the Great Plains within the United States as a model system. Results indicate that: (a) cool‐ and warm‐season, annual grass and broadleaf species can be grown for forage across the region; (b) forage production will be less risky than grain and seed crop production under predicted climate‐change scenarios; (c) grazing annual forages may offer advantages (e.g., nutrient cycling, improved soil structure, added revenue from livestock) over mechanically harvesting annual forages; (d) the lack of infrastructure and local markets impede the use of annual forages to diversify wheat‐based cropping systems in the region; and (e) limited networking among researchers hinders the advancement in knowledge on how annual forages can be used to improve dryland wheat system resilience.

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The introduction of cover crops as fallow replacement in the traditional cereal-based cropping system of the Northern Great Plains has the potential to decrease soil erosion, increase water infiltration, reduce weed pressure and improve soil health. However, there are concerns this might come at the cost of reduced production in the subsequent wheat crop due to soil water use by the cover crops. To determine this risk, a phased 2-year rotation of 15 different cover crop mixtures and winter wheat/spring wheat was established at the Northern Agricultural Research Center near Havre, MT from 2012 to 2020, or four rotation cycles. Controls included fallow–wheat and barley–wheat sequences. Cover crops and barley were terminated early July by haying, grazing or herbicide application. Yields were significantly decreased in wheat following cover crops in 3 out of 8 years, up to maximum of 1.4 t ha−1 (or 60%) for winter wheat following cool-season cover crop mixtures. However, cover crops also unexpectedly increased following wheat yields in 2018, possibly due in part to residual fertilizer. Within cool-, mid- and warm-season cover crop groups, individual mixtures did not show significant differences impact on following grain yields. Similarly, cover crop termination methods had no impact on spring or winter wheat grain yields in any of the 8 years considered. Wheat grain protein concentration was not affected by cover crop mixtures or termination treatments but was decreased in winter wheat following barley. Differences in soil water content across cover crop groups were only evident at the beginning of the third cycle in one field, but important reductions were observed below 15 cm in the last rotation cycle. In-season rainfall explained 43 and 13% of the variability in winter and spring wheat yields, respectively, compared to 2 and 1% for the previous year cover crop biomass. Further economic analyses are required to determine if the integration of livestock is necessary to mitigate the risks associated with the introduction of cover crops in replacement of fallow in the Northern Great Plains.

‘Willow Creek’ forage winter wheat (Triticum aestivum L.) (Reg. No. CV‐1032, PI 655073) was released by the Montana Agricultural Experiment Station. Awnletted cereal forages are widely used for hay production on integrated crop–livestock operations in the Northern Great Plains. Five awnletted winter wheat accessions were evaluated for forage characteristics in 1996 and 1997, and Willow Creek was selected directly from PI 306505. Willow Creek was evaluated in replicated trials for forage yield and quality, grain yield, and agronomic characteristics from 1998 through 2008. Willow Creek is an awnletted winter wheat cultivar with good performance as an annual hay crop under irrigated or rainfed conditions in Montana and Wyoming. This cultivar has excellent winterhardiness and is tall and late‐maturing. Willow Creek has good forage quality characteristics suitable for use by livestock in winter maintenance diets.

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