Most damage to soybeans by white-tailed deer occurs as light to moderate browsing spread out over large portions of the field. However, in rare cases where local deer densities are unusually high, repeated feeding by deer in a specific field, translating to repeated damage to individual plants, can result in severe damage to individual plants with those plants producing minimal yield.
- After emergence, deer bite off soybean plants down to a stub.
- Damage occurring above the first node will release the remaining axillary buds from dominance. The resultant growth from this type of damage is a double-stemmed plant.
- Because deer lack upper incisors, the bitten stem almost always will have a rough appearance, which can only be observed upon close inspection.
- Deer damage to soybean plants from the V4 stage of development and throughout the reproductive stages of growth, while the soybean plants are still green and succulent.
Groundhog damage to crops is concentrated around burrows, with peak feeding occurring at dawn and dusk.
- The area of damage appears as a semi-circle around the edge of the field. Groundhogs begin damaging soybean plants soon after emergence and continue damaging plants throughout the growing season as long as the plants are green and succulent.
- The area of damage will grow larger through time as the groundhogs seek out new growth further from their burrow.
- The damage is near their burrow entrance.
- Groundhog damage to newly emerged soybeans may result in missing plants (due to shoot removal below the cotyledons).
- Most groundhog damage is characterized by sharply cut stems at an angle. Groundhogs, like all rodents, have sharp incisors so they bite cleanly through the plant when they feed. Plants often are fed on repeatedly as soybean plants continue to sprout new leaflets.
- Weeds often dominate areas of groundhog damage due to the open space (caused by continual feeding on soybean plants in an area) and reduced competition for light and nutrients from soybean plants.
Rabbits cause some damage to soybeans, although the amount is trivial compared to damage by deer and groundhogs. Like rodents, damage from rabbits will leave a clean 45 degree edge on cut stems.
- Most rabbit damage occurs early in soybean plant development, but damage can occur until full seed.
Damage to soybeans by Canada Geese is generally limited to areas adjacent to or near an open body of water.
- Geese are grazers and are attracted to new succulent growth. While vegetative growth of soybeans continues until midway during the beginning seed stage, most goose damage occurs after emergence until plants are about 1-ft tall.
Concern over crop damage caused by wild turkey has grown in recent years. Purdue University researchers observing wildlife in the field and surveying crop fields for damage did not observe any measurable damage caused by wild turkey. This is consistent with research findings from other states. Turkeys in soybean fields feed primarily on insects, and any feeding on crops that takes place is minimal to negligible.
- Turkeys bit off the cotyledons from the main stem. More developed soybean plants (VC) also occurred in the field, but turkeys did not feed on these and apparently selectively fed on soybean plants that recently broke through the soil.