1. Nursery Production 3 Commercial Plant Production

2. Green Manures vs. Cover Crops

3. Green Manures Various plant species grown for a growing season on land not being used for production. Various plant species grown for a growing season on land not being used for production. Mowed down and incorporated into the soil while they are still “green”. Mowed down and incorporated into the soil while they are still “green”. Fast growing green manure crops may be mowed several times prior to incorporation. Fast growing green manure crops may be mowed several times prior to incorporation.

4. The following species have been used as green manures… Annual rye grass Annual rye grass Alfalfa Alfalfa Field corn Field corn Soybeans Soybeans Sudan grass Sudan grass Sudan x sorghum hybrids Sudan x sorghum hybrids

5. Sudan Grass

6. Sorghum: Important cereal grass native to Africa that ranks 4 th after rice, corn and wheat in terms of importance for human nutrition. There are 4 main types: 1) grain sorghums, 2) sweet sorghum (animal feed), 3) Sudan grass, and 4) Broom corn.

7. Benefits of Green Manure Crops Add organic matter to the soil. Add organic matter to the soil. Improves water holding capacity. Improves water holding capacity. Improves nutrient holding capacity (CEC). Improves nutrient holding capacity (CEC). Improves soil structure and aeration. Improves soil structure and aeration. Organic matter binds small soil particles together into larger aggregates. Organic matter binds small soil particles together into larger aggregates. Acts as a cover crop to help prevent soil erosion. Acts as a cover crop to help prevent soil erosion.

8. Why Use Green Manures In a B&B nursery operation every time a plant is harvested from the field some soil leaves the field as well. In a B&B nursery operation every time a plant is harvested from the field some soil leaves the field as well. After many years of harvesting the soil becomes depleted. After many years of harvesting the soil becomes depleted. Green manures can help “build” soil and replace some of what is being lost. Green manures can help “build” soil and replace some of what is being lost.

9. The amount of soil lost will depend upon the spacing and ball size. The amount of soil lost will depend upon the spacing and ball size. The table (next slide) assumes a spacing of 42 inches between rows and 36 inches between plants in a row. Also, assume all balls are 15 inches deep. The table (next slide) assumes a spacing of 42 inches between rows and 36 inches between plants in a row. Also, assume all balls are 15 inches deep. Soil Loss Data from a B&B Nursery

10. Ball diameter in inches Percent of soil removed during harvest (15 inch depth) 15 10 % 18 15 % 24 25 % 30 40 %

11. 15 inches Soil Loss from a Nursery Field

12. Cover Crops Similar to green manures. Similar to green manures. Protect the soil against erosion. Protect the soil against erosion.

13. Cover Crops Typically late summer/fall sown. Typically late summer/fall sown. Typically sown between the rows of nursery stock. Typically sown between the rows of nursery stock. Some research has shown that they help “harden-off” nursery stock by removing excess nitrogen from the field. Some research has shown that they help “harden-off” nursery stock by removing excess nitrogen from the field.

14. Oats: die off when the ground freezes. Oats: die off when the ground freezes. Buckwheat: dies off when the ground freezes. Buckwheat: dies off when the ground freezes. Winter rye: survives the winter and is incorporated in the spring. Winter rye: survives the winter and is incorporated in the spring. Rye grass: survives the winter and is incorporated in the spring. Rye grass: survives the winter and is incorporated in the spring.

15. The End