We will focus the experimental effort at the Wye Research & Education Center, using a randomized complete block design on approximately five-seven soybean varieties in fields bordering forested areas with long-term historical deer grazing pressure. We will place a 5-10’ diameter hog-wire deer exclosure on each plot to asses yield potential in the absence of grazing.
We will expand the use of 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 strip plot design:
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
To better understand soybean plant response to deer grazing, we plan to conduct a controlled herbivory simulation in a deer-proof fenced enclosure at the Wye Research & Education Center. We propose planting approximately 90 plants of each variety and leaving 30 without defoliation, 30 with weekly light defoliation (~33% defoliation), and 30 with weekly heavy defoliation (~66% defoliation). We will use weekly defoliation, which is consistent with observed deer grazing in 2021 that appeared to occur in heavy bouts approximately every 5-7 days. We plan to conduct this on the same five varieties that we will be testing in our strip plot design. We will sample a subset of plants for biomass at the R6 /R7 stage, when leaves begin to yellow, and harvest the rest of the plants for yield at normal harvest time.
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 morning (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 large 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.