⋅ By Eddie McGriff ⋅
Deer feeding in cotton has risen sharply over the last few years. Deer damage can cause severe stand losses, delayed maturity and yield reductions. In some cases, entire fields or large portions of fields can be lost. Replanting is costly in both time and money.
Deer feed on young cotton (less than 5 to 8 true leaves) until other preferred food sources become available. Deer feed primarily in the terminal buds, resulting in the loss of apical dominance and development of significant branching.
Most of the harvestable bolls are on multiple vegetative branches in deer-damaged cotton. If young plants are clipped below the cotyledon leaves, they do not recover.
In research conducted in North Carolina, cotton yield losses ranged from 18% to 36% (average of 29%) in affected areas when feeding occurred at the 4 to 5-leaf stage. Earlier feeding caused enough stand loss to justify replanting, resulting in delayed maturity and more severe yield losses.
Farmer’s Success With Sunn Hemp
Last year a demonstration project was conducted in a 40-acre field that Cherokee County, Alabama, grower Nick McMichen was considering abandoning due to severe deer damage in previous cotton and soybean crops. In a prior year, he had lost approximately 20 acres out of the 40 to deer damage and produced only 20 bales in the field.
In 2021, he planted sunn hemp, a summer annual legume, as a border crop and averaged close to two bales per acre. He lost less than two acres to deer damage. The deer preferred foraging on the sunn hemp rather than the cotton.
You can view my interview with Nick discussing his success planting sunn hemp as a border crop to prevent deer damage to his cotton on On The Farm in Alabama at Sunn Hemp Interview with Nick McMichen.
We still have many questions on the effectiveness of sunn hemp as a border crop in preventing or reducing deer damage to crops.
The Alabama Cotton Commission has graciously provided a grant to set up additional demonstration trials this year. We hope to plant sunn hemp on field borders in mid-to-late April, well before we plant cotton, allowing sunn hemp to establish ahead of cotton.
Hopefully, the deer will graze on sunn hemp rather than cotton.