This is not a comprehensive list of all research conducted at this time.
Management Considerations for Maize in Kura Clover Living Mulch.
Kura clover living mulch (KCLM) can be incorporated into upper-Midwestern row-crop production systems to provide perennial living groundcover during vulnerable spring and fall fallow periods. The cool season legume crop takes advantage of an extended growing season to increase carbon capture, provide habitat and nutrition to soil biota, and reduce nutrient loss relative to monocrop maize. These advantages, as well as observed improvements in water infiltration and reductions of soil and nitrate loss, may help to mitigate regionally important environmental impacts from intensive agricultural production systems in the upper Midwest. Designing KCLM systems for upper-Midwestern row-crop production requires consideration of the current production needs and management strategies. The objectives of this research were to (i) determine the effect of row establishment method and fertilizer N rate on maize yield and nitrogen use efficiency, (ii) identify the effect of row establishment method and fertilizer N source on the spatiotemporal distribution of clover and maize roots, and (iii) describe the effect of fertilizer N rate on the spatial and temporal distributions of clover biomass inputs, soil N concentrations, and nitrous oxide emissions within a KCLM for maize. These questions were addressed with two field experiments conducted at the Rosemount Research and Outreach Center in Rosemount, MN and one experiment conducted at Rosemount and the Arlington Research Station in Arlington, WI. The results of this research indicate that optimal row establishment methods during drought conditions depend on the severity of moisture stress, tillage intensity is positively correlated with clover root loss, maize roots were isolated to the tilled row zone to a depth of 0.20 m, and N2O emissions are alarmingly high from the interrow zone under normal growing conditions. The conclusions of this work are that aboveground clover biomass inputs provide a relatively small amount of N to the row crop and that N contributions are sourced from disturbed roots during row establishment. This indicates that N management in a KCLM-maize cropping system is highly dependent on stand history. Finally, 85% of N2O was emitted from the interrow zone in a KCLM under normal weather conditions. This finding indicates that hotspots of microbial denitrification are a potentially significant contributor to N2O emissions in KCLM systems, and that mitigation strategies may depend on clover residue management. Overall, KCLM systems may benefit maize producers in the upper Midwest, but care must be taken to mitigate known management challenges. Further research should be conducted to define remaining management questions and to identify strategies to mitigate high N2O emissions from these systems.
Alexander, J. R. (2022). Management Considerations for Maize in Kura Clover Living Mulch (Order No. 29212768). Available from Dissertations & Theses @ Big Ten Academic Alliance; ProQuest Dissertations & Theses Global; ProQuest Dissertations & Theses Global Closed Collection. (2706681377). http://login.ezproxy.lib.umn.edu/login?url=https://www.proquest.com/dissertations-theses/management-considerations-maize-kura-clover/docview/2706681377/se-2
Research from Pod to Pod: Harvest Time Optimization of Shatter-Resistant Pennycress, Camelina Integration into the Corn-Soybean Rotation, and Communicating Science Via Podcast.
Corn (Zea mays L.) and soybean (Glycine max L.] Merr) dominate the agricultural landscape in the Upper Midwest, but limits crop production to the summer months. There is a fallow period from late autumn through the spring that is associated with externalities such as nutrient loss and a lack of economically-viable crop production despite useable growing degree days during that period. Thus, pennycress (Thlaspi arvense L.) and camelina (Camelina sativa L.) are crops of interest for use during the corn-soybean fallow period. While both crops have been researched heavily for the past decade, questions about their production remain unanswered. Thus, the purpose of this dissertation is to further understand how pennycress harvest can be optimized for use within the corn-soybean rotation; observe the agronomic and economic dynamics when camelina is integrated into the corn-soybean rotation as a winter cash crop; further describe the effect of camelina in nutrient loss prevention over the typically-fallow period; and assess the role of camelina in the corn-soybean carbon cycle. All agronomic experiments were carried out over the 2019 and 2020 growing seasons. The pennycress experiment was conducted in Rosemount, MN, USA, while the camelina experiments were conducted in Morris and Rosemount, MN, USA. However, the research process does not end after data collection, analysis, and publication. For many scientists, there is a growing need to communicate findings with the general public rather than just to academic peers and industry and government stakeholders. This dissertation also explores the use of podcasting as a science communication medium though an experiential project, Hooked on Science.
Cubins, J. A. (2022). Research from Pod to Pod: Harvest Time Optimization of Shatter-Resistant Pennycress, Camelina Integration into the Corn-Soybean Rotation, and Communicating Science Via Podcast (Order No. 29992043). Available from Dissertations & Theses @ Big Ten Academic Alliance; ProQuest Dissertations & Theses Global; ProQuest Dissertations & Theses Global Closed Collection. (2747560409). http://login.ezproxy.lib.umn.edu/login?url=https://www.proquest.com/dissertations-theses/research-pod-harvest-time-optimization-shatter/docview/2747560409/se-2
Forage yield and profitability of grain-type intermediate wheatgrass under different harvest schedules.
Intermediate wheatgrass Thinopyrum intermedium (Host) Barkworth & Dewey] (IWG) is a perennial forage grass being domesticated to function as a perennial grain crop. Grain yield of improved, grain-type IWG cultivars decline by the third year of production and managing aging stands for forage production presents economic opportunities. Limited research is available on the response of second- and third-year grain-type IWG to different forage harvest schedules. We measured forage yield and nutritive value of grain-type IWG in the second and third year of production under nine forage harvest schedules varying in the timing of the first harvest (at boot, anthesis, or soft dough stage) and the number of fall harvests (none, one Sept.], or two Sept. and Nov.]). As timing of the first harvest was delayed and IWG maturity increased from boot to soft dough, yield increased from 2.4 to 3.7 Mg ha–1 and relative feed value decreased from 113 to 82. Yield at subsequent September and November harvests averaged 30% and 12% of the initial harvest yield, respectively. Total annual forage yield was not affected by the timing of the first harvest but was predictably greater for two or three harvests compared with one harvest; however, additional harvests in September and November decreased net returns. Grain-type IWG stands harvested in the third year after peak grain production have potential to provide forage similar to common perennial cool season forage grasses. Tradeoffs between forage yield and nutritive value should be considered when selecting the timing of the initial spring forage harvest.
Puka-Beals, J., Sheaffer, C. C., & Jungers, J. M. (2022). Forage yield and profitability of grain-type intermediate wheatgrass under different harvest schedules. Agrosystems, Geosciences & Environment, 5(3)https://doi.org/10.1002/agg2.20274
Exclusion and Repulsion of Popillia japonica (Coleoptera: Scarabaeidae) Using Selected Coverings on High Tunnel Structures for Primocane Red Raspberry.
Simple SummaryThe Japanese beetle, Popillia japonica Newman, has become an invasive pest of increasing concern for several high-value berry crops in the Midwest region of the U.S. since 2010. Due to the feeding injury caused by adult beetles, many producers have increased their use of foliar insecticides to manage P. japonica. With a goal to develop sustainable Integrated Pest Management (IPM) systems for raspberry production, we initiated a 3-year study to examine the potential for various high-tunnel production systems to suppress P. japonica populations, and thus minimize insecticide use in primocane (autumn maturing) raspberry. During each year of the study, we observed significant reductions in P. japonica beetle infestations (p < 0.05), under the high-tunnel, covered systems, compared to nearby open plots of raspberry.AbstractIn temperate climates, there has been an increasing interest by fruit growers to implement the use of high tunnels, using a variety of coverings, to extend the season for fruit production. High tunnels also provide an opportunity to enhance insect pest management, via physical exclusion, and thus support reductions in insecticide use. Due to increasing pest pressure by the Japanese beetle, Popillia japonica Newman, in Midwest U.S. raspberry, a 3-year study (2017–2019) was conducted to evaluate the efficacy of selected high tunnel coverings to suppress adult beetle populations and minimize adult feeding injury. During each year of the study, P. japonica adult beetles were significantly reduced under poly-based coverings, with the ends open, and when a fine, nylon-mesh was used to cover the ends (p < 0.05). The poly-based covering also resulted in moderately higher ambient temperatures, which may have influenced beetle movement, including a “repellency effect” that encouraged beetles to exit the high tunnel structures. Although P. japonica adults are known to feed on raspberry flower clusters, including fruit, the majority (73–92%) of beetle feeding in this study was observed on the foliage. The impact of high tunnels on P. japonica are discussed within the context of developing sustainable Integrated Pest Management (IPM) programs for raspberry production.
Burkness, E. C., Ebbenga, D. N., Toninato, A. G., & Hutchison, W. D. (2022). Exclusion and Repulsion of Popillia japonica (Coleoptera: Scarabaeidae) Using Selected Coverings on High Tunnel Structures for Primocane Red Raspberry. Insects, 13(9), 771. https://doi.org/10.3390/insects13090771
Comparison of methods to recover amaranth weed seeds from manure.
One pathway by which Palmer amaranth (Amaranthus palmeri S. Watson) invades new areas is through importation of contaminated livestock feed, which then contaminates land‐applied manure. If contaminated feed is suspected, detection tools are needed to test manure, but traditional methods are time consuming and often inconclusive. Although new genetic seed testing is making detection easier, methods to separate seed from contaminated manure are needed. Six methods were compared for their ability to recover 100 Palmer amaranth seeds added to bedded or nonbedded cattle manure: dry sieving, rinse sieving, manure saturation sieving without blending and with blending, and dispersion sieving without blending and with blending. Seed recovery was highest (>90%) with the rinse sieving method regardless of manure type. The dispersion methods are not recommended as they recovered <24.7% of seeds. Following each method, genetic testing successfully identified Palmer amaranth presence, indicating no interference of recovery method with DNA extraction.
Wilson, M. L., Brusa, A., Christensen, H., Strack, S., Alto, E., Allen, L. F., Cortus, S. D., Modderman, C., & Becker, R. L. (2022). Comparison of methods to recover amaranth weed seeds from manure. Agricultural & Environmental Letters, 7(1)https://doi.org/10.1002/ael2.20065
Perennial Flax: A Potential Cut Flower Crop
The genus Linum L. contains ≈200 primarily blue-flowered species, including several ornamentals, yet no reports exist regarding the cut flower potential of this genus. The objective of this study was to evaluate the cut flower potential of perennial flax cultivars (L. perenne L. ‘Blue Flax’ and ‘Sapphire’; Expt. 1, 2018) and accessions (L. austriacum L., L. lewisii Pursh., and L. perenne; Expt. 2, 2019), and record traits that will enable breeding and selection for improved cut flower performance. The mean vase life across both cultivars in Expt. 1 was 9.2 days. In Expt. 2, L. perenne had the longest average vase life (9.3 days), followed by L. austriacum (9.1 days) and L. lewisii (8.3 days). The floral preservative (Floralife 300) significantly increased vase life by an average of 1.7 days in Expt. 1, and 1.6 days in Expt. 2, and resulted in a significantly greater number of flowers (≈2x) in both experiments. Significant variation was observed among genotypes for most traits, including vase life (6.2 to 11.3 days) and number of flowers (1.3 to 10.5), highlighting the opportunities for improving the potential of cut flower perennial flax through breeding.
Tork, D. G., Anderson, N. O., Wyse, D. L., & Betts, K. J. (2022). Perennial Flax: A Potential Cut Flower Crop. HortScience, 57(2), 221-230. Retrieved Jun 23, 2025, from https://doi.org/10.21273/HORTSCI16098-21