2023
Evaluating Deer Preferences for Soybean Varieties and other Diversionary Food Plot Crops
Contributor/Checkoff:
Category:
Sustainable Production
Keywords:
Abiotic stressAgricultureLand Use Water supply
Lead Principal Investigator:
Luke Macaulay, University of Maryland
Co-Principal Investigators:
Project Code:
72673
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:
Protecting soybeans from deer damage can be complex, due to great variation in fields, the environment and even deer behavior. However, bare spots along timberlines and yield maps provide plenty of evidence that damage from deer can be costly. Farmers should take an integrated pest management approach to protecting their crops from deer. IPM tools for deer management include fencing, repellants, vegetation management and hunting. This project explored more about how forage soybeans provide a vegetative management tool, including how and where they have the greatest potential to limit deer feeding on commodity soybeans.
Key Beneficiaries:
#agronomists, #Extension agents, #farmers, #hunters, #soybean breeders
Unique Keywords:
#deer, #deer management, #environmental stress
Information And Results
Project Summary

Ongoing research has provided baseline information about the applicability of using various varieties of forage
soybeans as a diversion crop around a field perimeter to reduce damage to core growing areas. This project seeks to
continue that work and gain deeper understanding across a third growing season by continuing to assess 1) yield by
different forage soybean varieties and 2) deer activity and preferences of these varieties, 3) conducting regular forage
analyses across the growing season to discern whether deer prefer certain varieties at certain times and 4) providing a
demonstration seeds to farmers and assessing their qualitative and quantitative observations about the practice via a
survey. We seek to improve the project by modifying the planting layouts to 10’x13’ plots separated by 7’ alleyways
(instead of 20-30’ wide strips) to gather more precise deer grazing and preference data. We also seek to add additional
warm season diversion crops to the study.

Project Objectives

Ongoing research has provided baseline information about the applicability of using various varieties of forage soybeans as a diversion crop around a field perimeter to reduce damage to core growing areas. This project seeks to continue that work and gain deeper understanding across a third growing season by continuing to assess 1) yield by different forage
soybean varieties and 2) deer activity and preferences of these varieties, 3) conducting regular forage analyses across the growing season to discern whether deer prefer certain varieties at certain times and 4) providing a demonstration seeds to farmers and assessing their qualitative and quantitative observations about the practice via a survey. We seek to improve the project by modifying the planting layouts to 10’x13’ plots separated by 7’ alleyways (instead of 20-30’ wide strips) to gather more precise deer grazing and preference data. We also seek to add additional warm season diversion crops to the study.

Project Deliverables

We will focus the experimental effort at the Wye Research & Education Center, using a randomized complete block design on approximately five to seven soybean varieties and an additional food plot plantings including forage corn, lablab, iron clay cowpeas, American jointvetch, and alfalfa, each of which are species planted as food plots to attract deer for hunting.
We will plant these in fields bordering forested areas with long-term historical deer grazing pressure. We will place a 10’ diameter hog-wire deer enclosure on each plot to asses yield potential and plant production in the absence of grazing. We will use trail cameras to quantify deer grazing activity by different soybean varieties to gather improved information on deer preferences and activity across multiple replicates.

We propose planting the following varieties in a 10’x13’ plot design with 7’ alleyways:
1. Conventional Group 3.5 soybean - control
2. Group 4.7 forage soybean – GT1 Brier Ridge
3. Group 7 forage soybean – Big Fellow Eagle Seed brand
4. Group 6 forage soybean – Biologic
5. Conventional Group 5 soybean
6. Group 5 forage soybean – Biologic
7. Lablab
8. Iron clay cowpeas
9. American jointvetch
10. Alfalfa

We will conduct wet chemistry forage analysis every 3-4 weeks of the varieties we test in the study by clipping new leaf growth in the afternoon (when sugars are highest in plant tissue) and immediately placing samples them in a Styrofoam cooler with ice packs until they can be frozen at the research lab and mailed to a forage analysis lab.

Finally, we have reserved a significant portion of the budget to provide demonstration seeds of forage varieties at a collaborating farmer’s fields on the Eastern Shore to evaluate performance of these varieties in different soil types and with different deer population characteristics. We will prioritize provision of demonstration seed to farmers who have a history of yield-monitor data on proposed fields of planting to compare before and after effects of buffer treatments.

Progress Of Work

Update:
Research analysis is ongoing. We have presented research at 5 agronomy meetings to date, with two additional meetings in coming weeks. Farmers express hundreds of thousdands of dollars in savings from presentations. Full results will be available by the next update.

Final Project Results

Benefit To Soybean Farmers

Deer are the leading cause of crop damage by wildlife in Maryland, with most recent government estimates showing approximately $10 million in losses annually, with 77% of those losses attributable to deer (USDA NASS 2011). Maryland in particular faces greater challenges than many other soybean growing areas in the country due to smaller field sizes that are more often interspersed with and bordered by forested areas that provide refuge for deer, which emerge to graze highly palatable and nutritious soybeans. Farmers have regularly identified deer and wildlife damage as one of their top concerns, and frustrations by farmers are well documented in news media articles. Soybean yields in 2020 in certain fields at the Wye Research & Education Center in Queenstown, MD, were reduced by 20-30 bushels per acre in a field bordering a forested area. While hunting and crop damage permits allow some farmers to reduce deer population densities, some locations are not amenable to this due to factors such as landowners or neighbors that do not allow hunting, nocturnal grazing activity, and time required to harvest sufficient numbers of deer.

In 2021 and 2022, we engaged in research to better understand deer preferences and plant response in heavily damaged agricultural fields. In 2021, the study found a surprising performance of a less expensive Group 4.7 forage soybean, GT1 Brier Ridge from Lacrosse Seed as one of the higher performing varieties just after a Group 5.3 conventional soybean. These yields were considered by the farm manager as one of the best yields he’s observed out of these fields in many years. In 2022, we continued this work with an enhanced study design and greater numbers of wildlife trail cameras to monitor deer activity. We augmented this with a simulated grazing experiment for each of the varieties and monthly forage analysis. The results of 2022 study are forthcoming. We have begun to analyze deer grazing activity patterns against weather variables to try to predict the spikes in deer grazing we observed in the fields. Initial analysis suggests that rainfall in the prior 1-2 days is a significant predictor of deer grazing activity, and we plan to augment the analysis to incorporate wind and other factors.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.