Kentucky IPM Pest Information Pages
The Number of Green Cloverworms per Row Foot That Will Cause Economic Injury to Soybeans
(Excerpted from ENT-13 Insecticide Recommendations for Soybeans 1998, University of Kentucky Entomology Extension Publication ENT-13, Lexington, KY, 1998.)
How to Use These Tables
Because of the difficulty in determining the percentage defoliation, you may prefer to use the tables for determining approximate economic injury levels of the green cloverworm. First select the table most nearly representing the growth stage of your beans and the expected yield from the field. Then locate the estimated cost per acre of control (top line) and the estimated value per bushel of your bean (left-hand column). The number at the point where these lines and columns intersect is the approximate number of green cloverworms per foot of row that will cause ecomonic injury to soybeans. Do not allow infestations of this insect to exceed this level.
For example, suppose your soybeans are at the stage of early pod-fill, anticipated yield is 35 bushels per acre, and your cost of control is $6 per acre, and the estimated market value of your beans is $8 per bushel. The correct answer is 15 green cloverworms per foot of row.
| Number of Green Cloverworms per Row Foot Pre Bloom Stage - Anticipated Yield 25 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 14 | 15 | 16 | 17 | 18 |
| $7.00 | 13 | 14 | 15 | 16 | 17 |
| $8.00 | 13 | 14 | 15 | 16 | 17 |
| $9.00 | 13 | 13 | 14 | 15 | 16 |
| Number of Green Cloverworms per Row Foot Pre Bloom Stage - Anticipated Yield 35 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 13 | 14 | 15 | 15 | 16 |
| $7.00 | 12 | 13 | 14 | 15 | 15 |
| $8.00 | 12 | 13 | 13 | 14 | 15 |
| $9.00 | 11 | 12 | 13 | 13 | 14 |
| Number of Green Cloverworms per Row Foot Pre Bloom Stage - Anticipated Yield 45 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 12 | 12 | 13 | 14 | 15 |
| $7.00 | 11 | 12 | 13 | 13 | 14 |
| $8.00 | 11 | 12 | 13 | 13 | 13 |
| $9.00 | 11 | 11 | 12 | 13 | 13 |
| Number of Green Cloverworms per Row Foot Bloom Stage - Anticipated Yield 25 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 24 | 27 | 31 | 34 | 36 |
| $7.00 | 22 | 26 | 29 | 32 | 34 |
| $8.00 | 21 | 24 | 27 | 29 | 32 |
| $9.00 | 20 | 22 | 25 | 27 | 30 |
| Number of Green Cloverworms per Row Foot Bloom Stage - Anticipated Yield 35 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 20 | 23 | 26 | 29 | 31 |
| $7.00 | 19 | 22 | 25 | 27 | 29 |
| $8.00 | 17 | 20 | 22 | 25 | 27 |
| $9.00 | 15 | 18 | 20 | 22 | 24 |
| Number of Green Cloverworms per Row Foot Bloom Stage - Anticipated Yield 45 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 18 | 20 | 23 | 25 | 27 |
| $7.00 | 17 | 19 | 22 | 23 | 25 |
| $8.00 | 15 | 18 | 20 | 22 | 24 |
| $9.00 | 15 | 17 | 19 | 20 | 22 |
| Number of Green Cloverworms per Row Foot Pod Fill Stage - Anticipated Yield 25 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 22 | 25 | 28 | 31 | 34 |
| $7.00 | 20 | 23 | 26 | 29 | 31 |
| $8.00 | 18 | 22 | 24 | 27 | 29 |
| $9.00 | 17 | 20 | 22 | 25 | 27 |
| Number of Green Cloverworms per Row Foot Pod Fill Stage - Anticipated Yield 35 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 18 | 21 | 24 | 26 | 28 |
| $7.00 | 16 | 19 | 22 | 24 | 26 |
| $8.00 | 15 | 18 | 20 | 22 | 24 |
| $9.00 | 14 | 17 | 19 | 21 | 22 |
| Number of Green Cloverworms per Row Foot Pod Fill Stage - Anticipated Yield 45 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 15 | 18 | 20 | 22 | 25 |
| $7.00 | 14 | 17 | 19 | 21 | 22 |
| $8.00 | 13 | 15 | 18 | 20 | 21 |
| $9.00 | 13 | 15 | 16 | 18 | 20 |
| Number of Green Cloverworms per Row Foot Soybeans Approaching Maturity - Anticipated Yield 25 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 34 | 40 | 47 | 52 | 57 |
| $7.00 | 31 | 37 | 43 | 48 | 52 |
| $8.00 | 28 | 34 | 39 | 44 | 48 |
| $9.00 | 26 | 32 | 36 | 41 | 45 |
| Number of Green Cloverworms per Row Foot Soybeans Approaching Maturity - Anticipated Yield 35 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 27 | 33 | 38 | 43 | 47 |
| $7.00 | 25 | 30 | 34 | 38 | 42 |
| $8.00 | 22 | 27 | 32 | 36 | 39 |
| $9.00 | 21 | 25 | 29 | 33 | 36 |
| Number of Green Cloverworms per Row Foot Soybeans Approaching Maturity - Anticipated Yield 45 bu/A | |||||
|---|---|---|---|---|---|
| Cost of Treatment per Acre: | $6.00 | $8.00 | $10.00 | $12.00 | $14.00 |
| Soybean Value ($/bu) | |||||
| $6.00 | 23 | 28 | 32 | 36 | 40 |
| $7.00 | 21 | 25 | 29 | 33 | 36 |
| $8.00 | 19 | 23 | 27 | 30 | 34 |
| $9.00 | 18 | 21 | 25 | 28 | 31 |