Advances in automation and data science have led agriculturists to seek real-time, high-quality, high-volume crop data to accelerate crop improvement through breeding and to optimize agronomic practices. Breeders have recently gained massive data-collection capability in genome sequencing of plants. Faster phenotypic trait data collection and analysis relative to genetic data leads to faster and better selections in crop improvement. Furthermore, faster and higher-resolution crop data collection leads to greater capability for scientists and growers to improve precision-agriculture practices on increasingly larger farms; e.g., site-specific application of water and nutrients. Unmanned aerial vehicles (UAVs) have recently gained traction as agricultural data collection systems. Using UAVs for agricultural remote sensing is an innovative technology that differs from traditional remote sensing in more ways than strictly higher-resolution images; it provides many new and unique possibilities, as well as new and unique challenges. Herein we report on processes and lessons learned from year 1—the summer 2015 and winter 2016 growing seasons–of a large multidisciplinary project evaluating UAV images across a range of breeding and agronomic research trials on a large research farm. Included are team and project planning, UAV and sensor selection and integration, and data collection and analysis workflow. The study involved many crops and both breeding plots and agronomic fields. The project’s goal was to develop methods for UAVs to collect high-quality, high-volume crop data with fast turnaround time to field scientists. The project included five teams: Administration, Flight Operations, Sensors, Data Management, and Field Research. Four case studies involving multiple crops in breeding and agronomic applications add practical descriptive detail. Lessons learned include critical information on sensors, air vehicles, and configuration parameters for both. As the first and most comprehensive project of its kind to date, these lessons are particularly salient to researchers embarking on agricultural research with UAVs.

Pulse crops discussed in this review include soybean (Glycine max L.), dry pea (Pisum sativum L.), lentil (Lens culinaris Medik.), dry bean (Phaseolus vulgaris L.) and chickpea (Cicer arietinum L.). Basic maturity requirements, yield relationships with rainfall and temperature, relative yield comparisons, water relationships, water use efficiency (WUE), crop management, tillage systems, and the rotational impact of these crops on productivity were considered. With the exception of soybean, maturity requirements for pulse crops are met in most locations within the northern Great Plains. Yield was more closely related to growing season precipitation than maximum temperature for all pulse crops except dry bean and lentil. The inability to effectively relate weather parameters to dry pea and lentil yield may indicate broad adaptation of these two pulse crops within the northern Great Plains. Correlation analyses showed the productivity of chickpea, dry pea, and lentil to be most closely associated with each other and for dry bean productivity to be most closely associated with that of soybean, effectively grouping pulse crops into their respective cool‐ and warm‐season classifications. Dry pea and chickpea had high WUE values, similar to spring wheat (Triticum aestivum L.). Examination of plant water relations of these crops revealed an ability for chickpea and dry pea to grow at lower relative water contents than spring wheat. Increased wheat grain yield and/or protein following pulse crops under widely different N‐limiting growth conditions indicated a consistent N benefit provided by pulse crops to wheat. Four general research needs were identified. First, comparative adaptation among pulse crops remains poorly understood. Second, best management practices and key production risks remain incompletely characterized. Thirdly, the knowledge of rotational effects of pulse crops in the northern Great Plains remains imprecise and inadequate. Fourth, genetic improvement for early maturity, increased yield, improved harvestability, and disease resistance requires attention. Pulse crops are poised to play a much greater role in diversifying cropping systems in the northern Great Plains but require that these key research areas be addressed so that their production potential can be realized.

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With increased emphasis on bio-diesel fuels, the influence of spring planting on development of brown mustard (Brassica juncea cv. Arid), canola (B. napus cv. Hyola 401) and camelina (Camelina sativa cv. Boa) has become important. Field trials were conducted at Scottsbluff,

Current knowledge of yield potential and best agronomic management practices for perennial bioenergy grasses is primarily derived from small-scale and short-term studies, yet these studies inform policy at the national scale. In an effort to learn more about how bioenergy grasses perform across multiple locations and years, the U.S. Department of Energy (US DOE)/Sun Grant Initiative Regional Feedstock Partnership was initiated in 2008. The objectives of the Feedstock Partnership were to (1) provide a wide range of information for feedstock selection (species choice) and management practice options for a variety of regions and (2) develop national maps of potential feedstock yield for each of the herbaceous species evaluated. The Feedstock Partnership expands our previous understanding of the bioenergy potential of switchgrass, Miscanthus, sorghum, energycane, and prairie mixtures on Conservation Reserve Program land by conducting long-term, replicated trials of each species at diverse environments in the U.S. Trials were initiated between 2008 and 2010 and completed between 2012 and 2015 depending on species. Field-scale plots were utilized for switchgrass and Conservation Reserve Program trials to use traditional agricultural machinery. This is important as we know that the smaller scale studies often overestimated yield potential of some of these species. Insufficient vegetative propagules of energycane and Miscanthus prohibited farm-scale trials of these species. The Feedstock Partnership studies also confirmed that environmental differences across years and across sites had a large impact on biomass production. Nitrogen application had variable effects across feedstocks, but some nitrogen fertilizer generally had a positive effect. National yield potential maps were developed using PRISM-ELM for each species in the Feedstock Partnership. This manuscript, with the accompanying supplemental data, will be useful in making decisions about feedstock selection as well as agronomic practices across a wide region of the country.

Downy brome (Bromus tectorum L.), jointed goatgrass (Aegilops cylindrica Host), and volunteer cereal rye (Secale cereale L.) are winter annual grass weeds that are increasingly troublesome in the winter wheat (Triticum aestivum L. emend. Thell.)‐fallow rotation areas of the western USA. Six dryland cropping systems—continuous no‐till winter wheat, winter wheat‐fallow with fall tillage, winter wheat‐fallow with fall applied herbicide, winter wheat‐fallow‐fallow, winter wheat‐sunflower‐fallow, and winter wheat‐proso millet‐fallow—were compared for their effect on winter annual grass densities in winter wheat. Winter annual grass densities averaged 145, 4.4, and 0.4 plants/sq yard for the 1‐, 2‐, and 3‐yr systems, respectively. Eradication of the winter annual grasses was not achieved with any of the systems. Dockage and foreign material levels in wheat grain were lower in 3‐yr than in 2‐yr cropping systems. Jointed goatgrass was the most persistent annual grass investigated. The Problem Downy brome, jointed goatgrass, and volunteer cereal rye are increasingly troublesome winter annual grass weeds in the winter wheat‐fallow rotation areas of the USA. A 1989 mail survey of Colorado farmers indicated that these three weeds infested over 1.3 million acres of cropland in the state. The estimated cost of these infestations to Colorado wheat growers was over $20 million annually. Herbicides are not available to provide selective control of these grasses in winter wheat. Chemicals and tillage control these weeds during the fallow period, but sufficient seed usually remains to reinfest the following winter wheat crop. Crop rotation may be an effective way to control these weeds in winter wheat, but few reports exist of the effects of cropping systems on these weeds. Literature Summary Downy brome at densities of 20, 33, and 54 plants/sq yard reduced winter wheat yields by 10, 15, and 20070, respectively, when plants emerged within 14 d of winter wheat. Jointed goatgrass at 15 plantslsq yard reduced winter wheat yield in Colorado by 27 and 17% when emerging 0 and 6 wk after winter wheat, respectively. In addition to reducing winter wheat yield, jointed goatgrass also lowered grain quality by increasing dockage or foreign matter. In Oregon, 162 rye plantslsq yard reduced winter wheat yield by 33% when rye was removed in February compared with 69% when not removed. Jointed goatgrass spikelets and rye seed are serious contaminants of winter wheat grain. The longevity of downy brome seed varies widely. Freshly harvested downy brome seed exhibit a rapid and high germination percentage, suggesting that all viable seed will germinate when conditions are suitable. Viable seed were reported 5 yr after burial, however. Jointed goatgrass seed persists in undisturbed soil from 3 to 5 yr depending on site conditions. By the third year, less than 8% of seed buried 2 in (5 cm) deep survived. All seed were nondormant 3 yr after burial. The period of greatest jointed goatgrass seed loss from soil coincided with peak emergence in the fall. Le...