08/07/2026
🌱 WHAT’S IN THE FIELD? — DEER! 🦌
How much are deer really costing Pennsylvania soybean growers?
The Pennsylvania Soybean Board has funded a project to better understand the impact of deer on soybean production—and I’m participating in the project here in Lebanon County.
📍 Our Lebanon County research field is south of Umberger’s in Fontana, bordered by forest. This field typically produces 80–100 bushels of soybeans per acre, and the grower uses RTK and an accurate yield-monitoring system, giving us an excellent opportunity to measure the actual yield impact.
📷 We’re watching the deer.
We installed cameras at the most common entry points where deer enter the soybean field. Each week, we collect images and use AI and other techniques to identify individual deer and determine where and how heavily they are feeding.
We can then overlay that information with soybean yield maps to determine where deer feeding is translating into actual yield loss.
🚁 And then we got a surprise!
Bob Buzzard and Drew Oberholtzer from Lancaster Farming were kind enough to provide a thermal drone for our Lebanon County site. The thermal imagery allowed us to compare what we were seeing from ground cameras with the number of deer actually present in the field.
https://youtu.be/3DmUuX9vfB0?si=HYMNCNTbX9efm696
We were surprised by the sheer number of deer!
👉 The key takeaway: There may be many more deer using a soybean field than a grower realizes.
Using the Bushel app at Penn State, we can also map the areas being affected. The image from last week shows a classic edge effect, with deer feeding along the field edge and an hourglass-shaped feeding pattern extending toward the center of the field.
That shapefile can then be overlaid with the combine yield map to determine the actual impact on soybean yield.
🦌 Let's put the numbers into perspective.
At one point, we counted an estimated 70 deer in this field.
These calculations are estimates, but they illustrate the potential magnitude of the problem.
A deer may consume approximately 4% of its body weight in dry matter per day. If we assume an average 100-pound deer:
• 4% of 100 pounds = 4 pounds of dry matter/day
• Soybeans are approximately 80% water
• That means roughly 15 pounds of fresh soybean material per deer per day
If 70 deer were consuming 15 pounds each:
➡️ 1,050 pounds of soybean material per day
➡️ 31,500 pounds per month
➡️ Over approximately 120 days of summer feeding = 126,000 pounds
➡️ That's approximately 63 TONS of soybean material!
And that's from one group of deer in one field.
If you valued that 63 tons simply as forage at $50/ton, that's approximately $3,150 worth of forage consumed. The economic impact could easily be double or triple that amount depending on how yield loss and grain value are calculated.
The goal of this project is to determine just how much of that feeding actually translates into soybean yield loss.
What can growers do?
We've experimented with several approaches.
🌶️ Repellents: Pepper and onion sprays have provided limited success. As soybeans grow, new untreated growth becomes available and deer quickly figure that out.
⚡ Exclusion: Electric fencing and tall fencing can work very well, but the cost can make this option difficult for large fields.
🦌 Harvest management: Ultimately, managing deer numbers may be an important part of the solution.
Pennsylvania growers have several options for addressing crop damage, including Crop Damage permits, the Agriculture Deer Management Assistance Program (DMAP), July DMAP sign-ups, and management within established hunting seasons.
🦌 Hunters & Deer Management: Let’s Be Productive
As a hunter myself, I’ve always believed in harvesting a doe first before turning my attention toward bucks. If we want to manage deer populations effectively, we need to focus on harvesting enough does to make a meaningful impact on the herd.
For farmers who allow hunting on their property, it’s important to communicate expectations with hunters. Landowners should encourage—or even require—hunters to harvest does before pursuing bucks.
A productive deer management program benefits both the farmer and the wildlife resource. Fewer deer can mean less crop damage, while maintaining a healthy and balanced deer population.
🌽🦌 If hunters have the privilege of hunting your farm, make sure they are helping accomplish your deer management goals—not just hunting for antlers.
What are your thoughts? Should farmers require a doe harvest before allowing a buck to be harvested?
Whatever approach you take, contact your local Game Warden first to discuss the appropriate program and make sure deer are managed legally and humanely.
📹 Take a few minutes to watch the thermal drone video. The number of deer visible in the field really puts the problem into perspective.
Stay tuned! We're going to continue collecting data throughout the season and will eventually be able to compare deer feeding patterns directly with combine yield maps.
The big question is:
How many bushels are those deer really costing Pennsylvania soybean growers? 🌱🦌
https://www.youtube.com/watch?v=3DmUuX9vfB0
