Section:Plant & Soil Science Section:Plant & Soil Science Unit:Soil Management Unit:Soil Management Lesson Title: Use of Cropping Systems for Fertility Management Lesson Title: Use of Cropping Systems for Fertility Management

Continuous cropping The same crop is grown on the same land each year. The same crop is grown on the same land each year. This allows a producer to grow the most profitable crop. This allows a producer to grow the most profitable crop. They probably like growing that crop and have the proper equipment. They probably like growing that crop and have the proper equipment. From a fertility standpoint this is not a good strategy. From a fertility standpoint this is not a good strategy. Nutrients are depleted from the soil and more fertilizers then have to be applied. Nutrients are depleted from the soil and more fertilizers then have to be applied.

Crop rotation Not always the most profitable in the short run-but in the long run is better for soil fertility. Not always the most profitable in the short run-but in the long run is better for soil fertility. This has become more popular as producers search for better uses of the land with less “man-made” inputs. This has become more popular as producers search for better uses of the land with less “man-made” inputs.

Benefits of Crop Rotation Control of disease and insect populations Control of disease and insect populations By rotating away from a certain crop, disease that normally prey on a certain crop can be cleansed from the soil. By rotating away from a certain crop, disease that normally prey on a certain crop can be cleansed from the soil. One example is rotating soybeans to wheat instead of continuously growing soybeans. This practice has reduced soybean cyst nematode damage by up to 90 percent. One example is rotating soybeans to wheat instead of continuously growing soybeans. This practice has reduced soybean cyst nematode damage by up to 90 percent.

Benefits of Crop Rotation This practice also helps control weeds. This practice also helps control weeds. Some weeds flourish in one crop and perish in another. Some weeds flourish in one crop and perish in another. This reduces a herbicide treatments. This reduces a herbicide treatments. Also some crops suppress weeds by allelopathy, where one plant emits a chemical that suppresses growth of another. Also some crops suppress weeds by allelopathy, where one plant emits a chemical that suppresses growth of another.

Benefits of Crop Rotation Free source of nitrogen Free source of nitrogen Nitrogen fixing legumes (soybeans, alfalfa, peas) can be used to put nitrogen back into the soil for a crop that relies on nitrogen (corn, and wheat). Nitrogen fixing legumes (soybeans, alfalfa, peas) can be used to put nitrogen back into the soil for a crop that relies on nitrogen (corn, and wheat).

Benefits of Crop Rotation Improve soil organic matter and tilth. Improve soil organic matter and tilth. Using deep rooted plants like alfalfa improve subsoil. Using deep rooted plants like alfalfa improve subsoil.

Benefits of Crop Rotation Improved soil erosion plan. Improved soil erosion plan. When using row crops, small grains, and forage crops. When using row crops, small grains, and forage crops.

Crop Rotation Choices Row Crops Row Crops Planted in wide rows to accommodate irrigation, mechanical and chemical weed control. Planted in wide rows to accommodate irrigation, mechanical and chemical weed control. Common row crops would be corn, sorghum, soybeans, edible beans, and cotton. Common row crops would be corn, sorghum, soybeans, edible beans, and cotton.

Crop Rotation Choices Small Grains Small Grains Planted or sown in rows very close together. This allows for a faster ground cover. Planted or sown in rows very close together. This allows for a faster ground cover. These types of crops also leave a large amount of residue that aids in organic matter maintenance and aid in soil conservation. These types of crops also leave a large amount of residue that aids in organic matter maintenance and aid in soil conservation. These types of crops are good to begin a crop rotation system with. These types of crops are good to begin a crop rotation system with.

Crop Rotation Choices There are many crops that are best suited for particular environmental or soil conditions: There are many crops that are best suited for particular environmental or soil conditions: Wheat—dry areas with medium to fine textured soils Wheat—dry areas with medium to fine textured soils Oats—moister medium texture soils Oats—moister medium texture soils Rye –prefers sandy soils Rye –prefers sandy soils Barley—tolerant of saline soils Barley—tolerant of saline soils

Crop Rotation Choices Forages Forages Improve soil tilth, increase organic matter and aid in erosion control. Improve soil tilth, increase organic matter and aid in erosion control. Forages such as alfalfa fix nitrogen in the soil. Forages such as alfalfa fix nitrogen in the soil. Alfalfa has a long taproot and works well in breaking up soil hard pans. Alfalfa has a long taproot and works well in breaking up soil hard pans.

Double Cropping Systems Double cropping is planting two crops to the same land area within one growing season. Double cropping is planting two crops to the same land area within one growing season. A common example is planting beans into wheat stubble A common example is planting beans into wheat stubble

Advantages of Double Cropping Eliminates seedbed prep for the final crop Eliminates seedbed prep for the final crop Less erosion problems Less erosion problems Increased organic matter due to increased green matter of two crops. Increased organic matter due to increased green matter of two crops.

Disadvantages of Double Cropping Two crops draw on more soil nutrients and available water Two crops draw on more soil nutrients and available water Creates a greater management level. Creates a greater management level.

Dryland Farming Farming in areas of low rainfall with no other supplemental irrigation. Farming in areas of low rainfall with no other supplemental irrigation.

Dryland Farming Land is usually summer fallowed—harvested one year and allowed to rest the following cropping season. Land is usually summer fallowed—harvested one year and allowed to rest the following cropping season. This give time to increase soil nutrients, and soil water. This give time to increase soil nutrients, and soil water. A fallowed field can store about 25 percent of the rainfall in the soil for the following crop. A fallowed field can store about 25 percent of the rainfall in the soil for the following crop. GREAT CAUTION should be taken to avoid erosion problems, organic matter loss, and saline seeps (where saline water rises to the top of the fallow ground and leaves salt deposits) on fallowed ground. GREAT CAUTION should be taken to avoid erosion problems, organic matter loss, and saline seeps (where saline water rises to the top of the fallow ground and leaves salt deposits) on fallowed ground.

Sustainable Agriculture A philosophy of using ALL resources available to ensure that over the long term agriculture is still a viable industry. A philosophy of using ALL resources available to ensure that over the long term agriculture is still a viable industry. This means taking measures to protect resources while ensuing productivity. This means taking measures to protect resources while ensuing productivity. Top yields are not the goal, the goal is to have profitable yields based on REDUCED input costs. Top yields are not the goal, the goal is to have profitable yields based on REDUCED input costs. Soil management (erosion and fertility management) is a crucial tool to a sustainable agriculture. Soil management (erosion and fertility management) is a crucial tool to a sustainable agriculture.

Sustainable Agriculture Watch the following episode (#9) on different sustainable agriculture practices. Segment 3 is the most applicable. Watch the following episode (#9) on different sustainable agriculture practices. Segment 3 is the most applicable. rtners/partners.html rtners/partners.html rtners/partners.html rtners/partners.html