Integrated Crop and Livestock Systems: Dryland Crop Rotations to Improve Economic and Ecological Sustainability in the Central High Plains

Final Report for SW05-117

Project Type: Research and Education
Funds awarded in 2005: $212,928.00
Projected End Date: 12/31/2009
Region: Western
State: Wyoming
Principal Investigator:
Dr. Steve Paisley
University of Wyoming
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Project Information


Project SW05-117 focuses on developing additional dryland cropping options for producers in southeastern Wyoming, northeastern Colorado and western Nebraska in order to improve economic sustainability while reducing erosion and improving soil quality. This three-year project looks at integrating alternative forages such as winter pea, spring pea and medic as alternative cropping system rotations compared to the traditional dryland rotations of wheat-fallow. Soil quality, production (both livestock gain and crop production) and economic analysis will be used to evaluate and compare the sustainability of these practices vs. conventional farming.

Project Objectives:

The objectives of this project are to establish integrated dryland cash-crop/forage/livestock systems and to evaluate the impacts on soil quality and profitability. This project represents the initial three years of a multi-year study evaluating dryland cropping system opportunities in southeastern Wyoming.

Sub-objectives are:

1. Establish and evaluate the use of both annual and regenerative legumes (peas and medic) in an integrated crop, forage and livestock system.

2. Measure and compare soil quality for the alternative crop, forage and livestock systems vs. traditional wheat-fallow and perennial pasture.

3. Evaluate profitability of each of the proposed alternative crop, forage and livestock systems.

4. Compare long-term sustainability of permanent pastures vs. sustainable cropping and livestock systems on existing wheat-fallow dryland fields.


Traditional dryland wheat-fallow cropping systems are still the mainstay in the Central High Plains, but a combination of climatic, economic and management factors are making these traditional cropping systems less and less popular. Although the 14-month fallow associated with the traditional winter wheat-summer fallow system (WW-SF) has generally guaranteed successful wheat seedling establishment, the system is notoriously inefficient. In summary, adverse effects of fallow include lower profit potential, decreased soil organic matter, declining soil fertility, inefficient use of the water resource, root zone leaching of nutrients, soil erosion, air pollution, and surface and groundwater pollution. There is a need to identify and develop appropriate legume/cereal/livestock systems that fit the natural resource base. This project was designed to incorporate forages (both annual and perennial) and livestock into the existing wheat-fallow system which will address the WSARE goals of enhancing the quality and productivity of soil, conserve soil and water, promote crop and livestock diversification and evaluate the environmental and economic implications of adopting sustainable agricultural systems. It was planned to be done on a scale that would attract producer interest. This study was planned to establish three integrated dryland crop, forage and livestock systems that would be compared with the traditional wheat-fallow system and permanent pasture. The integrated systems would be extended crop rotations of wheat that either incorporated livestock grazing, or produced transportable feed stocks in the form of hay and grain. The systems would be evaluated in terms soil quality, production (grain, forage, and livestock gain) and most importantly, profitability.


Materials and methods:

Project site is 360 acres of cropland currently in wheat/fallow strips located at the University of Wyoming Sustainable Agriculture Research and Extension Center (SAREC) research facility, located near Lingle, Wyoming (Figure 1). Brief descriptions of the proposed systems and crop rotations are provided below.

Proposed Crop Rotation Systems are shown in the attached Figure 1, With three pastures assigned to each cropping system, all phases of each rotation would be represented within each year of the study.

The perimeter of the site was fenced and underground water lines installed in Year 1. Twelve pastures and the perennial grass paddock were established based on soil type, soil testing and terrain to minimize differences in crop production potential. It was originally proposed that during each year of the three-year project, all steps of each cropping system would be represented to minimize the year effect on overall production.

When adequate forage was produced, replacement heifers from the UW SAREC research herd were used to determine livestock gain and plant response to grazing. Heifers remained on grazed pastures from early May until early to mid-June. Forage quality and standing dry matter estimates were taken systematically throughout the grazing period. Under the direction of Steve Paisley, stocking rates for each pasture were managed to provide similar grazing pressure across all treatments, and samples of selected pea lines were subjected to laboratory tests known to provide information regarding potential nutritive value for livestock. Forage and grain samples were analyzed for dry matter, and ash and crude protein.

Research results and discussion:
Objective 1: Establish and evaluate the use of both annual and regenerative legumes (peas & medic) in an integrated crop, forage and livestock system
  1. The project site, consisting of 360 acres of dryland wheat fallow cropland at the University of Wyoming SAREC near Lingle, Wyoming, was chemical fallowed over the spring and summer of 2006. The paddock design and layout proceeded in the manner as shown in Figure 1 starting in mid-September 2006 when the first winter annual crops were sown. A John Deere 1560 no-till drill with 7.5 inch row spacing was used to seed winter wheat, Austrian winter pea and medic at a seeding rate 60, 60, and 13.5 lbs/acre, respectively.

    a) All pastures were sampled during the fall of 2006, resulting in eight samples per pasture (as indicated by the dots on Figures 1 and 2).

    b) Despite the extremely dry conditions, 2006 autumn emergence of the winter wheat and peas was acceptable. This was because of the special effort to sow these crops into soil moisture at 1.5 to 2 inches of soil depth. However, overall precipitation for this area has been well below average (Table 1), affecting our ability to establish our medic and winter pea paddocks.

    c) Beginning in the spring of 2007, all water lines for the proposed livestock grazing paddocks were trenched.

    d) All fencing for the perimeter of project site was completed in May of 2007 (see attached photos).

    e) Despite what appeared to be proper fall establishment of medic and winter pea crops, continued extremely dry weather resulted in very poor stands and very little forage production. Despite very low forage production, winter pea plots were sampled every two weeks to monitor forage quality (Table 2) and overall DM production was measured on June 1, 2007 to document the low forage production (Table 3). Forage production averaged 192 lb/acre and 274 lb/acre, respectively, for the north and south plot replications of winter peas.

    f) Medic, because of its small seed size (the seed is roughly only twice the size of alfalfa), required shallow sowing (¼ to ½ inch). As consequence of the extreme dry conditions that persisted into December the medic emergence in the autumn was poor. Medic paddocks were seeded in the fall of 2006 and evaluated during the spring of 2007. Stands in spring 2007 were very poor, and the paddocks were eventually sprayed to control goat grass stands.

    g) Perennial pastures were seeded in the spring of 2007 with stands to be evaluated in spring 2008 to determine establishment, etc.

    h) The dryland wheat crop was drilled with a John Deere 1560 No-till drill on September 10th through September 12th 2007 @ 60#’s per acre, using the variety Goodstreak. Wheat paddocks were mechanically harvested July 22nd through July 28th 2008, yielding approximately 18 bushels per acre. Several of the strips were only partially harvested because of the severe Jointed Goatgrass stands.

    i) University of Wyoming bred heifers grazed Austrian winter pea pastures for three weeks in June 2008. All pea replicate pastures were fenced together to provide enough forage for the time period, and although weight gain data was recorded, heifers were only able to maintain weight. Grazing dates and weights were recorded.

    j) Evaluation of Medic plots by visiting faculty Roy Latta, Science Leader; Mallee Research Station, Walpeup(below).

    i. Jason Bagley's thesis and lit review found suitable production, quality, winter hardiness and seed softening to validate Laramie as a suitable component of a dryland wheat pasture system. Gatua establishment studies (talked of drought constraints) recommended drilling into standing stubble.

    ii. Gatua trial established Laramie medic at SAREC (small plots) in 2004 that regenerated successfully and productively in the fallow phase of 2007/08. Chemical fallow restricted seed set.

    iii. Clear July 2008 photographic evidence below of no invasiveness outside original plot area.

    iv. Moccassin Montana failed establishment in the fall of 2007, both inexperimental and demonstration situations. Ley farming trial was sown on September 17, 2007 with a direct drill machine with press wheels, (compactors) following at ~ 1 cm. There was < 1 plant/m2 established (August 19, 2008, 11 months after sowing) which has both very recently senesced and in some cases continued to bloom. Doubtful if the pod produced was mature enough to germinate in 2008.

    v. SAREC Suggestions are that Paisley Krall study did not establish Laramie successfully in the Fall/Spring of 2006/07 or the Spring of 2007/08. (<1 plt/m2 in plots 202 and 104 summer 2008)

    vi. Review of 2006/07 sown medic seed pods available for establishment in fall of 2008 suggests:

    1. Plot 201 has 20% of site with very low medic pod numbers, 80% has none.

    2. Plot 103 with 60% of plot area having approximately 40 pods/m2, potentially 20-40 plants/m2 but still large areas of bare ground.

    3. Plot 202 and 104 (2007/08 established medic) have variable densities of annual medic established 0 - 4 plts/m2, however the plots have good numbers of plants on the north end of plots (Double seeding rate? Lifting drill shallow sowing? Increased compaction?)

    4. However it is unlikely that the spring sown medic will produce mature seed from the most recent August rainfall >1 inch 15/8/08.

    5. Suggestions are there has been a lack of day to day on-site project management based on the current poor/lack of weed control and grazing management, probably exacerbated by poor Laramie establishment.

    6. Commercial – Alton Lerwick established Laramie successfully in the spring of 2008. It was sown March 26 at 5-6 lbs/ac with a direct drill seeder system into a wet soil profile but with no significant precipitation until 50 points on April 10 allowed germination and emergence.

    7. On August 7, 2008 the Laramie medic at Lerwick site was found to have produced approximately 1.8 t/ha (1600 lbs/ac) of biomass (see below) having had 1 pod set (with no germinable seed on August 7 2008) and a second group of pods still maturing. This was achieved under a dense cover of tumbleweeds (picture below).

    k) Research recommendations:

    i. Herbicide recommendations essential (have to have clear messages in relation to cleaning up weeds, both grass and broadleaf herbicide tolerance?)

    ii. Establishment - Seed needs to be in place when rain arrives (dry sowing? Sowing pods?) Gatua tried pods in a low technology system but no germination occurred, I am not aware that he measured viable seeds in the pods.

    iii. Soil water content and water use: Re to help explain establishment failure and subsequent yield loss in crops:

    l) Preliminary Research:
    Seed germination study: After visiting and evaluating the Lerwick site, seed pods from the SAREC Paisley/Krall project were evaluated along with seed pods from the Lerwick producer site.
    This preliminary research indicates that based on the high percentage of hard seed found at SAREC, even if optimum conditions were to occur at the Paisley/Krall research site, very little germination would occur due to the high percentage of hard seed.

    l) Additional medic research:
    Publications in the UW Animal Science 2008 and 2009 Research Report

    Adaptation of annual legumes as winter annuals on the central high plains for use in integrated crop and livestock systems. Steve Paisley, Extension Beef Cattle Specialist, Christopher Loehr, Graduate Research Assistant UW, Frances Loehr, Graduate Research Assistant UW, Jim Krall, Director of Research, Jerry Nachtman Research Associate II, SAREC.

    Nine different legumes were tested for winter survival at the James C. Hageman Sustainable Agriculture Research and Extension Center (SAREC) near Lingle Wyoming. Varieties tested were: Laramie Medic (Medicago rigidula), Austrian Winter Pea (Pisum sativum L.), Common Hairy vetch (Vicia villosa Roth), Namoi Wolly Pod vetch (Vicia villosa), Rasina vetch (Vicia sativa), Morava vetch (Vicia Sativa), Indian Head lentil (Lens. culinaris), and Toni lentil (Lens. Culinaris). Namoi Wooly Pod vetch, Rasina vetch, Morava vetch, and Toni lentil are all Australian species being tested for their suitability to southeastern Wyoming. The other varieties are common to the United States but not necessarily to southeastern Wyoming. The eight legumes were planted on August 28, 2007 and October 2, 2008 to be evaluated for winter survivability. Each variety was replicated four times in a randomized complete block design. Seeds were inoculated prior to planting. Plots measured 5 ft. by 20 ft. Row spacing measured 14 inches. Winter survival evaluations were taken on April 3, 2008 and March 4, 2009. Harvesting of the first year’s plots took place on May 5, 2008. The second year’s plots have yet to be harvested Two meters of row cover were harvested by hand for comparison of forage production. The entire experiment was also duplicated in the spring of 2008 and 2009 to evaluate each species’ suitability as a summer crop. Planting took place on April 4, 2008 and May 19, 2009. Harvesting took place on July 1, 2008 and July 2, 2009.

    After testing all eight varieties for winter survival and production, it would appear that only Austrian winter pea, Laramie medic, and Hairy vetch are suited to be used as winter legumes in a ley farming system in southeastern Wyoming (Tables 4-8). However, 2009 data seems to suggest that Toni lentil and Namoi wolly pod vetch may also be possibilities. Additional research may be needed to make a definite conclusion. Economic research may also be needed to decide if ley farming is indeed a profitable option for Wyoming producers.

Research Objective 2: Measure and compare soil quality for the alternative crop, forage and livestock systems vs. traditional wheat-fallow and perennial pasture.

Once the proper crop rotations are established, Dr. Gary Hergert will establish baseline conditions on both quantitative and qualitative factors including soil organic matter, total organic carbon, organic nitrogen, and C:N ratio. Sampling will be done when the treatment plots are established to reflect spatial variability (soils, slope, landscape position) plus average conditions within the larger experimental units. These points will be logged with GPS/GIS technology and the plots re-sampled at the same points after three years.

** Because we were unable to establish any of the rotations to an acceptable level, this part of the project was not completed and associated funding was returned.

Research Objective 3: Evaluate profitability of each of the proposed alternative crop, forage and livestock systems

The original project proposed that when the complete cycle of cropping systems were completed, the economic analysis comparing the traditional dryland wheat/fallow system vs. alternative legume crop and cattle grazing rotations would be conducted by James Sedman and James Jacobs. This would be accomplished by developing enterprise budgets, showing per unit costs and returns for alternative crop and livestock enterprises. Specifically, input and machinery costs for respective field operations would be computed throughout the production cycle.

** Because we failed to establish the proposed cropping rotations, the economic analysis was not completed.

Research Objective 4: Compare long-term sustainability of permanent pastures vs. sustainable cropping and livestock systems on existing wheat-fallow dryland fields

** Because establishment of cropping systems was never achieved we could not complete this comparison

Research conclusions:

Impact on producers, communities, and farming practices:

Based on preliminary data, we had originally estimated that the proposed alternative cropping systems including Austrian Winter pea would generate an additional $12/acre. Based on a 50% fallow replacement this means an additional $1.1 million/yr for the agricultural economy of southeastern Wyoming alone. Adoption of these practices in adjacent states would result in substantially larger returns, as estimated below in the economic impact.

While some of the Austrian winter pea, Laramie medic, and Hairy vetch appear to have acceptable winter survivability in our environment, we were unable to establish Laramie medic in our cropping system and because of the prolonged drought through 2006 – 2008 coinciding with this project, we also failed at producing acceptable Austrian winter pea or winter wheat crops as well. While the results are extremely disappointing, it may be valuable to know that because of our typical dry fall weather, establishment of the ley farming system in SE Wyoming is difficult at best.

Participation Summary

Research Outcomes

No research outcomes

Education and Outreach

Participation Summary:

Education and outreach methods and analyses:

Chris Loehr, S.I. Paisley, James M. Krall, Jack T. Cecil, Jerry Nachtman. 2009. Adaptation of fall sown medic, pea, vetch, and lentil to the 2007-2009 climate of the High Plains of Wyoming. Department of Animal Science 2009 Research Report.

Chris Loehr, S.I. Paisley, , F. Loehr, J.M. Krall, J. Nachtman. 2008. Adaptation of annual legumes as winter annuals on the central high plains for use in integrated crop and livestock systems. Research brief, Department of Animal Science 2008 Research Report.

Education and Outreach Outcomes

Recommendations for education and outreach:

Areas needing additional study

There is still a need for alternative cropping systems for dryland wheat producers in the arid western plains. Continued investigation of winter pea varieties, as well as alternative forage crops, may help to address this need. We will continue to investigate alternative fall-sown forage crops to provide cropping alternatives to producers in this region

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.