Relay cropping involves overlapping growing phases of two crops and is used to increase plant cover on the landscape, land productivity, and crop diversity. We evaluated relay cropping three summer crops (chickpea [Cicer arietinum L.], sunflower [Helianthus annuus L.], and safflower [Carthamus tinctorius L.]) with winter camelina (Camelina sativa (L.) Crantz) between 2022 and 2025 to determine suitability of each summer crop for relay cropping with winter camelina. Relay crop treatment resulted in slower canopy closure following winter camelina harvest and delayed development of all summer crops relative to monocrop treatments. Winter camelina yield averaged 1133, 904, and 206 kg ha-1 in 2023, 2024, and 2025. Relay crop chickpea yield (2015 kg ha-1) was lower than monocrop chickpea (3397 kg ha-1) in 2023, but not in 2024 (1492 and 1524 kg ha-1, respectively) and seed protein was unaffected. Relay crop sunflower yield (1508 kg ha-1), oil content (503 g kg-1), and oil yield (760 kg ha-1) were lower than monocrop sunflower (4428 kg ha-1, 548 g kg-1, and 2426 kg ha-1, respectively) in 2023 but not 2025. Safflower seed yield and seed oil yield were not affected by relay crop treatment either year. Spring weed populations were not affected by relay crop treatment, but all three summer crops had higher weed biomass in the relay crop treatment before summer crop harvest in fall of 2023. All three crops have potential to be relay cropped with winter camelina, and future work on agronomic management will be needed to optimize the system.

Adoption of oilseeds is expanding in the United States Corn Belt, but their influence on soil aggregation, an indicator for susceptibility to surface wind or water erosion, is scarce. Soil physical properties were measured in rotation treatments of two seasonally different rotation systems: (1) winter oilseeds versus winter fallow and (2) summer oilseeds versus corn ( Zea mays L.). Soil was collected from the top 5 cm of both rotations in the fall, following soybean ( Glycine max L.) harvest, and separated into six dry aggregate size distribution (DASD) fractions used to calculate the mean weight diameter (MWD), the wind erodible fraction (WEF; 0–1.0 mm aggregates), and the ability of aggregates to remain stable in water (ASW; 1–2 and 2‐3‐mm aggregates). Winter camelina ( Camelina sativa L.) had a lower WEF (0.22 ± 0.029) compared to winter fallow (0.26 ± 0.029). Summer oilseed treatments had a significant influence on DASD with >50% of aggregates >2 mm in the summer oilseed treatments and >50% of aggregates >3 mm in the corn treatment. The corn–soybean, Calendula officinalis L.–soybean, and Brassica napas L.–soybean rotations did not differ significantly in MWD (3.59, 3.44, and 3.45, respectively) or WEF (0.20, 0.12, and 0.22, respectively) but had lower MWD and WEF than the Cuphea viscosissima Jacq. × Cuphea lancelota W.T. Aiton‐soybean, Echium plantagineaum L.‐ ‐soybean, and soybean–soybean rotations (MWD: 3.19, 3.23, and 3.22 and WEF: 0.28, 0.26, and 0.25, respectively). Neither winter nor summer oilseeds altered ASW. Nevertheless, MWD and WEF shifts indicate that oilseed crops improved soil aggregation and soil susceptibility to erosive forces of wind.

Winter camelina (Camelina sativa L.) can be grown as an intermediate oilseed crop following spring wheat (Triticum aestivum L.) with soybean (Glycine max L.) relay planted the following spring into the camelina, producing three crops in 2 years. Winter camelina provides early spring ground cover that reduces soil erosion and improves water quality; however, camelina fall biomass production is limited. Here, we investigated whether interseeding tillage radish (Raphanus sativus L.) in the fall between rows of winter camelina improved fall soil cover, spring soil moisture, nitrogen cycling, and crop productivity of the winter camelina-soybean relay crop system. Soybean was planted into the winter-terminated tillage radish rows prior to camelina flowering in the spring. Data on NDVI, soil moisture, crop biomass, soil N and P content, weed populations, crop seed yield, and oil content were measured. Intercropping tillage radish with winter camelina increased fall soil coverage and early spring water infiltration over winter camelina alone in 1 out of 2 years. Tillage radish did not affect camelina growth or productivity, but had a positive effect on soybean yield (2703 kg ha-1), oil content (222 kg ha-1), and oil yield (600 kg ha-1) as well as the total oil yield of camelina plus soybean (996 kg ha-1) relative to the camelina only treatment (2401, 216, 520, and 925 kg ha-1, respectively). Fall intercropping of tillage radish into winter camelina may be used to improve environmental benefits and overall system productivity of the winter camelina-soybean relay crop system.

Crotalaria juncea (sunn hemp) is a tropical forage legume used as a cover, forage, and fiber crop. Sunn hemp seed production occurs primarily in India because it requires short days to flower and set seed. Seeds available for production are typically non-specific genotypes instead of true breeding varieties. As sunn hemp is grown in more locations, understanding not only its performance in different growing conditions but also variations in genotype performance is critical for production management. We evaluated the growth and biomass accumulation of four genotypes (KMB1, KMB2, Thailand Original Sunn, and ‘Tropic Sunn’) of sunn hemp grown in northern semi-arid and humid-continental environments, Wyoming (Adams ‘22 and ‘23 (irrigated), Wyarno ‘23 (rainfed)) and Minnesota (Morris ‘22 and ‘23), USA. Thailand Original Sunn had the fastest growth rate (height over time) but the slowest canopy closure (NDVI over time), while KMB1 had the slowest growth rate but the fastest canopy closure. While growth rates varied among sunn hemp germplasm, there were no marked differences in biomass accumulation when harvested at 60 and 90 days after planting. Although the genotype did not have a significant effect on biomass accumulation, the environment affected not only growth but also biomass accumulation. At 60 DAP, the sunn hemp biomass averaged 1836, 489, 2459, 3334, and 731 kg ha−1 in the Adams ‘22, Adams ‘23, Morris ‘22, Morris ‘23, and Wyarno ‘23 environments, respectively. At 90 DAP, the sunn hemp biomass averaged 6459, 4573, 7979, 7403, and 2220 kg ha−1 in the Adams ‘22, Adams ‘23, Morris ‘22, Morris ‘23, and Wyarno ‘23 environments, respectively. The growth rate, canopy closure, and biomass accumulation differed when compared between the semi-arid environments and the humid-continental environment, with the humid-continental environment producing faster growth and higher biomass. These findings support the hypothesis that genotypes are likely to perform as predicted within growing regions, but there may be room to improve performance in different environments through selective breeding.

Declining natural pollinator populations are a potential threat to global food supplies. Mass flowering summer annual oilseeds can provide much needed crop diversity and floral resources to support pollinator communities. We evaluated how managing planting date affects floral phenology, floral accumulation (flower coverage time x flower area), pollinator visitation, pollinator diversity and yield of nine oilseed crops. Borage (Borago officinalis L.), calendula (Calendula officinalis L.), crambe (Crambe abyssinica Hochst), cuphea (Cuphea viscosissima Jacq. x Cuphea lanceolata W. T. Aiton), echium (Echium plantagineum L.), flax (Linum usitatissimum L.), spring camelina (Camelina sativa (L.) Crantz), spring canola (Brassica napus L.) and sunflower [Helianthus annuus L.] were grown in Morris, Minnesota during the summers of 2013 and 2014. Each crop was planted on a "standard" planting date of mid-May and additional planting dates of early May, early June and early July. Shifting planting dates affected flowering phenology, floral accumulation, pollinator visitation and crop yield. Later planting dates led to later onset of flowering for all crops and affected total floral accumulation for crambe, cuphea and echium. Pollinator visitations changed with planting date and were generally greater with the later planting dates. At least two of the four planting dates supported high yield for each crop. The ability to maintain high crop yield across a window of planting dates affords growers management options for their fields and can be used to design complementary resource pairing and improve pollinator health through crop diversification and management.

The integrated crop-livestock systems of the northern High Plains are lacking in annual legumes that meet the nutrient demands of beef cattle when alfalfa (Medicago sativa) is in limited supply. We investigated the biomass accumulation, regrowth biomass, and nutritive value of sunn hemp (Crotalaria juncea) in response to initial harvest day and cutting height in irrigated and dryland studies in Wyoming. Net biomass accumulations in 105-day growing period were 4.4 tons acre(-1) under irrigation and 0.7 tons acre(-1) in dryland conditions. Initial harvest day after planting (iDAP) affected initial and regrowth biomass accumulation but did not affect net biomass accumulation in irrigated or dryland studies. Regrowth and net biomass accumulations were affected by cutting height in the irrigated study only. Nutritive value concentrations were significantly affected by iDAP in both irrigated and dryland studies. Under irrigation, net nutrient accumulation was not affected by iDAP but was significantly greater with a cutting height of 4.2 inches compared to 2.5- and 6-inch heights. In contrast, the dryland study, net nutrient accumulation was not affected by cutting height but was higher in 55-105 iDAP than 45 iDAP. In the irrigated study, a cutting height of 4.2 inches produced net accumulations higher in both biomass accumulation and nutritive value. In the dryland study a harvest time of 55-105 iDAP produced the highest net accumulation regardless of harvest time or cutting height. Sunn hemp can be harvested once or twice in a 105-day growing season to produce biomass and essential nutrients for livestock feeding.

Climate change and its complex interactions with crops and cropping systems present challenges to agricultural production. Resilient systems that provide food security for a burgeoning population, built by improving crops and developing new alternative cropping systems, are needed to cope with the myriad impacts climate change has on agriculture. Relay cropping is a systems strategy to sustainably intensify crop production and provide environmental benefits. Relay cropping involves interseeding one plant species into an established crop, creating a temporary spatial-temporal overlap of the two crops. This system keeps living plant cover on the agricultural landscape most of the year, which has implications for adapting to and even mitigating climate change impacts. As global warming progresses, land area suitable for relay cropping or producing more than one crop per year will likely expand to more northerly latitudes. The following review specifically focuses on relay cropping, giving examples of how it can potentially improve agricultural system resilience and adaptability to climate change and reduce greenhouse gas emissions, while also addressing potential limitations. More research is needed to improve crop genetics, crop combinations, and management practices best suited for relay cropping to further develop systems that can adapt to changing weed and insect dynamics as well as improve nitrogen and water use under current and future predictions of climate change.

The ancient wheats einkorn (Triticum monococcum L.), emmer (Triticum turgidum L.), and spelt (Triticum spelta L.) are currently attracting renewed consumer interest due to their unique flavor profiles and high nutritional quality compared with modern bread (Triticum aestivum L.) and durum (Triticum durum L.) wheat. Ancient wheats are well suited for production in marginal lands and may be well adapted to Wyoming growing conditions. A 2-year study was conducted in three locations in Wyoming (Powell, Sheridan, and Lingle, WY) under irrigated and rainfed conditions to identify the agronomic potential of spring planted spelt, emmer, and einkorn in Wyoming. Across locations, grain yields averaged 832 lbs acre-1 for einkorn, 1,492 lbs acre-1 for emmer, and 1064 lbs acre-1 for spelt with 14.7-15.9% protein. In 2017, irrigated spring wheat yield in Wyoming averaged 3642 lbs acre-1 and dryland yield averaged 1020 lbs acre-1. The Powell irrigated location was the highest yielding and perhaps the best suited for ancient wheat production. Continued research on variety selection and management is needed to further improve the yield and profitability of ancient wheats in Wyoming. Unique nutrition of ancient wheat has renewed consumer interest and increased value.Yield potential of spring ancient wheats is higher in northern Wyoming growing regions.Spring emmer had the highest yield of ancient wheats in Wyoming.

Decreased agricultural diversity from extensive use of the corn (Zea mays L.)- soybean (Glycine max (L.) Merr.) rotation and occasional inclusion of spring wheat (Triticum aestivum L.), has threatened cropping system sustainability. Using specialty oilseeds crops to extend the corn-soybean rotation might improve yields and promote sustainability. We tested whether corn, soybean, and wheat yields would be improved in a rotation following oilseed crops versus corn or soybean. In Phase 1, replicated blocks of nine different flowering oilseeds and two traditional grain crops (corn and soybean) were grown. In phase 2, corn, soybean, and wheat were planted in replicated blocks perpendicular to the previous year crops. This 2-year rotation was repeated for three site-years, two in Morris, MN and one in Brookings, SD. Soil water balance was evaluated during Phase 1 of the rotation to determine seasonal water use. Potential N mineralization was measured in the spring prior to planting in a subset of phase 1 treatments (spring canola, cuphea, corn, and soybean). Linear mixed models were used to analyze Phase 2 corn, soybean and wheat yield responses to previous crop. N dynamics and water use responses to phase 1 crops were also analyzed with mixed models. Corn yield was higher with any previous crop other than corn. Soybean and wheat yields did not significantly respond to previous crop. Yield patterns were partially explained by N mineralization potential and previous crop water use. Spring canola treatments provided higher potential net nitrification compared to corn. Canola, camelina, borage, and crambe had lower seasonal water use than both corn and soybean in at least one site-year. This short-term study indicated that corn and soybean yields following specialty oilseed crops had similar yields to a traditional corn-soybean rotation. Further, oilseed crops in rotation provided additional environmental benefits.

Sustainablesuccess of the Northern High Plains (NHP) crop and livestock industry is limited by market accessibility, infertile soils, short growing seasons, and availability of high nutritive value, low-cost feed. Adoption of the tropical legume, Crotalaria juncea L. (commonly known as sunn hemp), into NHP cropping systems could improve the sustainability of the rotation by fitting into summer growing windows and being used as a hay alternative. Rainfed and irrigated studies were conducted in Lingle, WY, to determine the target planting date for sunn hemp in the NHP. Later planting day of year was correlated with increased percent establishment in the rainfed study but had no effect in the irrigated study. In both irrigated and rainfed studies, planting between 8 June and 18 June maximized biomass accumulation. Biomass accumulation 60 d after planting ranged from 0.2 to 5.1 Mg ha(-1) in the rainfed study and 1.2 to 4.2 Mg ha(-1) in the irrigated study. For both irrigated and rainfed studies, the nutritive value of sunn hemp was high with crude protein greater than 220 g Kg(-1), acid detergent fiber less than 305 g Kg(-1), neutral detergent fiber less than 331 g Kg(-1), relative feed values above 183, and total digestible nutrients greater than 590 g Kg(-1). Planting date did not affect nutritive value. Sunn hemp grown in the NHP has a 60-d yield potential 5.1 Mg ha(-1), should be planted between 8-18 June to 60-d biomass production, and has nutritive value equivalent to supreme quality alfalfa (Medicago sativa L.) hay.

Relay-cropping of the novel oilseeds winter camelina (Camelina sativa L.) and pennycress (Thlaspi arvense L.) with short-season crops such as soybean [Glycine max (L.) Merr.] can provide economic and environmental incentives for adopting winter cover crop practices in the U.S. Upper Midwest. However, their ability to reduce nutrient loss in surface runoff is unknown. Accordingly, surface runoff and quality were evaluated during three seasonal phases (cover, intercrop, and soybean) over 2 yr in four cover crop-soybean treatments (pennycress, winter camelina, forage radish [Raphanus sativus L.], and winter rye [Secale cereale L.]) compared with no-till and chisel-till fallow treatments. Runoff was collected with Gerlach troughs and assessed for concentrations and loads of NO3 - -N, total mineral N, soluble reactive P (SRP), and total suspended solids (TSS). Cumulative runoff and nutrient loads were greater during the winter cover phase because of increased snow melt and freeze-thaw released nutrients from living vegetation. In contrast, cumulative TSS was greater during intercrop and soybean phases due to high-intensity rainfall events with an open soybean canopy. Average TSS loads during the intercrop phase were reduced by 75% in pennycress compared with fallow and radish treatments. During the soybean phase, average TSS, total mineral N, and SRP loads were generally elevated in cover crop treatments compared with no-till. Overwintering cover crops may contribute to mobility of nutrients solubilized from living or decomposing vegetation; however, this was balanced by their potential to reduce runoff and TSS during high-intensity spring rains.

Winter cover crops might reduce nutrient loss to leaching in the Upper Midwest. New oilseed-bearing cash cover crops, such as winter camelina ( L.) and pennycress ( L.), may provide needed incentives. However, the abilities of these crops to sequester labile soil nutrients are unknown. To address this unknown, N in shoot biomass, plant-available N and P in soil, and NO-N and soluble reactive P in soil water collected from lysimeters placed at 30, 60, and 100 cm were measured in cover crop and fallow treatments established in spring wheat ( L.) stubble and followed through a cover crop-soybean [ (L.) Merr.] rotation. Five no-till cover treatments (forage radish [ L.], winter rye [ L.], field pennycress, and winter camelina) were compared with two fallow treatments (chisel till and no-till). Pennycress and winter camelina were harvested at maturity after relay sowing of soybean. Winter rye and radish sequestered more N in autumn shoot biomass, ranging from 26 to 38 kg N ha, but overwintering oilseeds matched or exceeded N uptake in spring, ranging 28 to 49 kg N ha before soybean planting. Nitrogen uptake was reflected by reductions in soil water NO-N during cover crop and intercropping phases for all cover treatments (mean = 4 mg L), compared with fallow treatments (mean = 31 mg L). Cash cover crops like pennycress and winter camelina provide both environmental and potential economic resources to growers. They are cash-generating crops able to sequester labile soil nutrients, which protects and promotes soil health from autumn through early summer.

Core Ideas Net income from relay cropping was rarely different from that of mono‐cropping. A 25‐cm oilseed row spacing was likely too narrow for optimal soybean growth. Further domestication of oilseeds will likely improve relay cropping with soybean. ABSTRACTCover crops can serve as a valuable management tool for improving soil and water quality, but are an added expense for farmers. We evaluated the yields and economics of four cover crops and two winter fallow treatments in a spring wheat (Triticum aestivum L.)–soybean [Glycine max (L.) Merr.] rotation at three sites in Minnesota. The four cover crop treatments were winter rye (Secale cereal L.), forage radish (Raphanus sativus L.), winter camelina [Camelina sativa (L.) Crantz], and pennycress (Thlaspi arvense L.) planted into spring wheat stubble. The fallow treatments consisted of no‐tilled and conventionally tilled soil. Radish winterkilled and rye was terminated chemically before planting soybean in early May. Soybean was inter‐seeded between rows of camelina and pennycress at the same time it was planted in other treatments. Camelina and pennycress were harvested over soybean seedlings in late June. Camelina yields ranged from 600 to 1100 kg ha−1, while pennycress ranged from 900 to 1550 kg ha−1. Mono‐cropped soybean averaged 1819, 3510, and 4180 kg ha−1 in northern, central, and southern Minnesota, respectively. Soybean seedlings under oilseed cover crop canopies exhibited light‐stress, which likely reduced soybean yield in these treatments by 22 to 30%. When oilseed and inter‐seeded soybean yields were combined, total seed yields generally were equal to or exceeded those of mono‐cropped soybean. In addition, net income for inter‐seeded systems was typically equivalent to mono‐cropped soybean. Improvements in net income are likely needed before the benefits of oilseed cover crops are fully realized.

Over-wintering crops are known to reduce nutrients in soil leachate in spring, but little economic incentive is available to grow these crops in the Upper Midwest. New oilseed-bearing cash cover crops, such as winter camelina and pennycress, may provide the needed incentives. However, the abilities of these crops to sequester labile soil nutrients are unknown. We used lysimeters buried at 30, 60, and 100 cm to examine nitrate and soil reactive phosphorus (SRP) in six soybean cropping system treatments: clean till, no-till, and autumn-seeded radish, winter rye, pennycress, and winter camelina. Radish winter-killed naturally, winter rye was killed with a glyphosate, and pennycress and winter camelina were allowed to mature naturally after relay sowing of soybean. Leachate chemistry was studied for the autumn, spring, and summer periods over two growing season. In autumn, leachates under radish and winter rye tended to have the lowest nitrate levels. In spring, differences among nitrate levels across treatments were greater than at any other time period, with values much lower under pennycress and winter camelina treatments than other treatments. In summer, nitrate levels were more uniform, with the lowest values occurring where soybean grew best. In general, cash cover crops like pennycress and winter camelina provide both environmental and economic resources to growers in that they represent cash-generating grain crops that sequester labile soil nutrients, especially in spring, and protect and promote soil health from autumn through early summer.

‘FourOsix’ (Reg. no. CV‐1153, PI 689753) hard red winter wheat (Triticum aestivum L.) was developed and released by the Montana Agricultural Experiment Station in 2018. FourOsix was derived from a composite of five single crosses of the predominant cultivar Yellowstone to advanced Montana breeding lines. FourOsix was developed using a modified bulk breeding method and selected as an F5:6 headrow. FourOsix was tested under the experimental number MT1465 in Montana yield trials from 2014 to 2018. FourOsix is a high‐yielding, winter‐hardy hard red winter wheat cultivar with medium maturity, medium to high grain protein concentration, and excellent milling and baking quality. FourOsix was released for its excellent grain yield performance in winter wheat production environments of Montana, with earlier heading date, reduced plant height, improved grain volume weight, and improved stripe rust resistance relative to Yellowstone.

The continuing pollinator crisis is due, in part, to the lack of year-round floral resources. In intensive farming regions, such as the Upper Midwest (UMW) of the USA, natural and pastoral vegetation largely has been replaced by annual crops such as maize (Zea mays L.), soyabean (Glycine max L.) and wheat (Triticum spp.). Neither the energy (nectar) nor protein (pollen) needs of pollinating and other beneficial insects are being met sufficiently by the new, high-intensity, agricultural landscape. Several potentially useful oilseed crops can be grown in the UMW, and many of these oilseeds are highly attractive to beneficial insects. Prior research showed that some of these oilseeds produced abundant nectar, but their corresponding values for pollen production are unknown. Accordingly, the aim of our research was to document pollen (and protein) production per unit area of twelve oilseed crops grown in Minnesota and associate these values with levels of beneficial insect visitation during anthesis. Our results show that oilseed crops such as camelina (Camelina sativa L.), flax (Linum usitatissimum L.) and pennycress (Thlaspi arvense L.) produce relatively little pollen (40kg/ha); borage (Borago officinalis L.), calendula (Calendula officinalis L.), canola (Brassica napus L.), crambe (Crambe abyssianica Hochst) and cuphea (Cuphea viscosissima Jacq. x Cuphea lanceolata W. T. Aiton) produce bountiful pollen resources (50-150kg/ha); and oilseed echium (Echium plantagineum L.) generates massive amounts of pollen (>400kg/ha), about 50% of which is protein. Our study is unique in presenting a season-long perspective of pollen production in alternative oilseed crops, a resource valuable to pollen-feeding insects such as managed and wild bees. Diversification of UMW landscapes that includes alternative oilseed crops such as oilseed echium and cuphea can potentially provide a ready source of pollen and protein to help combat pollinator decline.

Pennycress (Thlaspi arvense L.), a common winter annual weed species in North America, has received attention in recent years as a potential oilseed feedstock for biofuel production but little is known about best practices for its production as a managed crop. Therefore, the objective of this study was to determine optimum sowing date to maximize pennycress yield, oil content, and crude protein. Four field experiments with 10 unique sowing and harvest dates over 3 crop years were conducted in Morris, MN, USA. Pennycress was no-till seeded from late August to late October at a rate of 6.7kgha−1. Seed yield averaged between 99 and 1109kgha−1 when sown in late October and early September, respectively, while oil content for the same sowing period averaged between 26.8 and 36.3%, respectively. Yield was not related to in-season environmental variables, such as cumulative precipitation, soil temperature at planting, or accumulated photohydrothermal time. However, oil content was maximized under greater precipitation (r2=0.86), warmer soil temperatures (r2=0.62) and greater photohydrothermal time when modeled at 2, 4, 6, 8, 25, 50 and 100cm soil depths (between r2=0.53 to r2=0.85). Results indicate that environment conditions favoring a long maturation period increased oil accumulation in seeds. Conversely, a longer growth period reduced seed crude protein. Although pennycress protein is expected to have industrial uses, managing for yield and oil content is preferred. Therefore sowing pennycress in late August through September in the northern Corn Belt will maximize yields and oil content.

Pollinating insects are in decline throughout the world, driven by a combination of factors including the loss of forage resources. The maize (Zea mays L.)– and soybean [Glycine max (L.) Merr.]–dominated agriculture of the Central and Midwestern United States produces a landscape relatively devoid of nectar and pollen resources. Introducing specialty oilseeds into current crop rotations could provide abundant floral resources for pollinating insects as well as a high‐value crop for growers. We investigated the nectar sugar resources and insect visitation throughout flower anthesis of nine specialty oilseed crops in west‐central Minnesota and eastern South Dakota during the 2013 and 2014 growing seasons. Total sugar produced over anthesis (TS) was highest for echium (Echium plantagineum L.) at 472 kg ha−1. Canola (Brassica napus L.), crambe (Crambe abyssinica Hochst.), echium, borage (Borago officinalis L.), and cuphea (Cuphea viscosissima Jacq. × Cuphea lanceolata W. T. Aiton) produced enough sugar in one hectare to supply the annual sugar needs of a least one managed honey bee (Apis mellifera L.) colony. Pollinators visited flowers of all crops, with as many as 90 insects min−1 observed. Our study is unique as we measured nectar sugar production, flower density, and insect visitation throughout anthesis for multiple specialty oilseed crops, providing a seasonwide perspective of the flux of nectar resources for pollinators. Adding specialty oilseed crops into current crop rotations could aid in reversing pollinator decline by providing forage resources that are lacking in the current agricultural landscape.

Interest from the US commercial aviation industry and commitments established by the US Navy and Air Force to use renewable fuels has spurred interest in identifying and developing crops for renewable aviation fuel. Concern regarding greenhouse gas emissions associated with land‐use change and shifting land grown for food to feedstock production for fuel has encouraged the concept of intensifying current prominent cropping systems through various double cropping strategies. Camelina (Camelina sativa L.) and field pennycress (Thlaspi arvense L.) are two winter oilseed crops that could potentially be integrated into the corn (Zea mays L.)–soybean [(Glycine max (L.) Merr.] cropping system, which is the prominent cropping system in the US Corn Belt. In addition to providing a feedstock for renewable aviation fuel production, integrating these crops into corn–soybean cropping systems could also potentially provide a range of ecosystem services. Some of these include soil protection from wind and water erosion, soil organic C (SOC) sequestration, water quality improvement through nitrate reduction, and a food source for pollinators. However, integration of these crops into corn–soybean cropping systems also carries possible limitations, such as potential yield reductions of the subsequent soybean crop. This review identifies and discusses some of the key benefits and constraints of integrating camelina or field pennycress into corn–soybean cropping systems and identifies generalized areas for potential adoption in the US Corn Belt.