Brian Fulmer of Juniper Dale Farm in Pen Argyl, PA told a group of local farmers his reasons for wanting to experiment with cover crops this year: To keep the soil in place, as well as to increase the nitrogen supply in his soil for sweet corn next year. “In other words,” he says, “the whole nine yards.”
Northampton County Cooperative Extension is taking part in an 11-county wide study of cover crops in Pennsylvania. They are using 15 different crops including: Aroostock Rye, Tillage Radish, Oats, Crimson Clover, Annual Ryegrass, Wheat, Triticale, Austrian Winter Pea, Hairy Vetch (Lancaster County), Hairy Vetch (Texas), Persian Clover, and Red Clover, as well as different combinations of the plants. The experiment looks at how well the different cover crops grow in local conditions and the most effective planting time.
Each plant has its own advantage. Winter pea is high in nitrogen. Rye has excellent nutrient uptake ability. Tillage radishes work as a “bio drill” (it breaks up the soil for your future crops). But they also have their disadvantages (some are very hard to control). After walking around the 15 different plots and discussing the soil and cost benefits of the different crops, the group of cover crop-curious farmers were left on their own to decide which cover would be the best for their own farms and soils.
Remember cover crops are an excellent way to stem soil erosion and depending on the crop you choose, can help enrich your soil with nutrients leading to healthier crops in the years to come.
Sunday, November 22, 2009
Friday, November 20, 2009
Are you using more compost or manure than you should?
“Putting on too much compost is expensive and it pollutes.” - Klaas Martens. Organic Grain Farmer. Finger Lakes, New York.
We all know that using organic nutrients such as compost and manure have many benefits. They can increase organic matter, improve soil structure and build a reserve of nutrients in the soil. But the difficulty with using compost and manure is they release nutrients slowly at rates that we cannot always predict. Often the ratios of nitrogen to phosphorus and potassium don’t match what our plants need.
Recently I learned that there can be too much of a good thing. I spoke last week to Klaas Martens an organic grain farmer in the Finger Lakes region of New York. Working with Thomas Bjorkman, a researcher from Cornell, they applied a poultry based compost at different rates in order to determine if they could predict the best compost applications using traditional soil test recommendations. They found that compost applied at rates based on the soil test, did not increase yields or increase organic matter. But, weeds grew better! Where compost was applied at double the recommended rate, weeds were twice as tall (Bjorkman, 2008).
Over application severely impacts the environment. Agriculture account s for 73% of nitrogen and 64% of phosphorus in the Chesapeake Bay. Excess nitrogen easily leaches into ground water and into streams. Phosphorus binds tightly to soil particles that are washed into streams. These nutrients encourage growth of algae and aquatic weeds that use up the oxygen dissolved in the water, making it impossible for fish and other organisms that need this oxygen to survive.
Even the best organic farmers commonly over apply. Researchers surveying organic farms in the Northeast found that vegetable farms that relied on compost often had surplus nutrients, as much as 180-200 lb P and N/ acre – yr in excess (Drinkwater et. al. 2005).
It is easy to apply too much. We often apply at a rate of 1” or 2”s which is easier than calculating how many tons we are applying. Researchers at Penn State did just this, applying 1” or 2” of dairy based compost compared to inorganic fertilizer before peppers. They found that adding just 1” of compost released 441 lbs N/acre compared to the 100 lbs N/acre the peppers needed. This was considering that compost generally only releases 15% of its N per year. Another 2,450 lbs of N/ acre was still tied up in soil organic matter (Sanchez, 2008).
Don’t guess, soil test. Test your compost and soil. If your soil nutrients are too high (over 320 P2O5, 335 K2O, 2505 CaO, 490 MgO lbs/ acre), compost may not be the best choice this year. You will know your soil test is saying you are to high when the bars go into the “exceeds crop needs” section of the table.
Don’t guess, compost test. There is no such thing as the average compost. The average nitrogen content of 126 dairy manure based compost samples analyzed at Penn State was 1.45% nitrogen. But when we looked at three individual dairy manure compost samples from the same farm, the amount of nitrogen applied in 20 ton/ acre of compost ranged from 510, to 415 to 842 lb/ acre. Phosphorus ranged from 88, to 146 to 200.
If your soil test is okay calculate how much N,P,K is available based on your compost test. The compost you apply will be decomposed by bacteria and fungi that live in the soil which release the nutrients slowly over time. Use simple calculations available in Penn State publications “Managing Organic Nutrient Sources” to evaluate how much compost to apply to meet your crop needs. We have also put together a flow chart to help you decide which calculations to do for your farm. Ask for the “Organic Nutrient Sources Decision Making Tree.”
We all know that using organic nutrients such as compost and manure have many benefits. They can increase organic matter, improve soil structure and build a reserve of nutrients in the soil. But the difficulty with using compost and manure is they release nutrients slowly at rates that we cannot always predict. Often the ratios of nitrogen to phosphorus and potassium don’t match what our plants need.
Recently I learned that there can be too much of a good thing. I spoke last week to Klaas Martens an organic grain farmer in the Finger Lakes region of New York. Working with Thomas Bjorkman, a researcher from Cornell, they applied a poultry based compost at different rates in order to determine if they could predict the best compost applications using traditional soil test recommendations. They found that compost applied at rates based on the soil test, did not increase yields or increase organic matter. But, weeds grew better! Where compost was applied at double the recommended rate, weeds were twice as tall (Bjorkman, 2008).
Over application severely impacts the environment. Agriculture account s for 73% of nitrogen and 64% of phosphorus in the Chesapeake Bay. Excess nitrogen easily leaches into ground water and into streams. Phosphorus binds tightly to soil particles that are washed into streams. These nutrients encourage growth of algae and aquatic weeds that use up the oxygen dissolved in the water, making it impossible for fish and other organisms that need this oxygen to survive.
Even the best organic farmers commonly over apply. Researchers surveying organic farms in the Northeast found that vegetable farms that relied on compost often had surplus nutrients, as much as 180-200 lb P and N/ acre – yr in excess (Drinkwater et. al. 2005).
It is easy to apply too much. We often apply at a rate of 1” or 2”s which is easier than calculating how many tons we are applying. Researchers at Penn State did just this, applying 1” or 2” of dairy based compost compared to inorganic fertilizer before peppers. They found that adding just 1” of compost released 441 lbs N/acre compared to the 100 lbs N/acre the peppers needed. This was considering that compost generally only releases 15% of its N per year. Another 2,450 lbs of N/ acre was still tied up in soil organic matter (Sanchez, 2008).
Don’t guess, soil test. Test your compost and soil. If your soil nutrients are too high (over 320 P2O5, 335 K2O, 2505 CaO, 490 MgO lbs/ acre), compost may not be the best choice this year. You will know your soil test is saying you are to high when the bars go into the “exceeds crop needs” section of the table.
Don’t guess, compost test. There is no such thing as the average compost. The average nitrogen content of 126 dairy manure based compost samples analyzed at Penn State was 1.45% nitrogen. But when we looked at three individual dairy manure compost samples from the same farm, the amount of nitrogen applied in 20 ton/ acre of compost ranged from 510, to 415 to 842 lb/ acre. Phosphorus ranged from 88, to 146 to 200.
If your soil test is okay calculate how much N,P,K is available based on your compost test. The compost you apply will be decomposed by bacteria and fungi that live in the soil which release the nutrients slowly over time. Use simple calculations available in Penn State publications “Managing Organic Nutrient Sources” to evaluate how much compost to apply to meet your crop needs. We have also put together a flow chart to help you decide which calculations to do for your farm. Ask for the “Organic Nutrient Sources Decision Making Tree.”
Friday, November 6, 2009
Innovative Cover Crops
Despite heavy mud and threats of rain more than 100 people came to Groff’s field day at Cedar Meadow Farm October 28th. Organized by Cooperative Extension folks came out to see novel cover crops and combinations.
Groff collected cover crop seed from Europe, Australia, the Midwest and the West to trial alongside old favorites from our area. “The prices for cover crop seed are always fluctuating,” says Groff, “If we can find additional cover crop varieties that do well in our area that will give us greater options if vetch or other seed becomes too expensive.” Combinations and unusual cover crops might also provide additional benefits, such as building soil structure.
A few highlights:
Tillage Radish is a forage radish that Groff grows for seed and promotes for its ability to break up hard pans. The fine roots projecting from a large tap root corkscrew through compacted soil providing a channel for crop roots and water infiltration. Groff’s latest interest is planting radish at a low rate of 2-3 lbs/ acre with wheat. “The word mellow is most popular,” Groff said for soil after radishes or radish small grain combinations.
Indian Head lentil was one experimental legume cover crop Groff planted. He brought it from the Midwest where they love it. “You would think if it grows in North Dakota it would grow here,” Groff said. But in Pennsylvania we have dramatic freeze thaw cycles and Indian Head lentil seems to fail most years. In comparison Early Cover vetch seems to tolerate freeze thaw cycles the best.
Although Common Vetch does not over winter well it may have an important niche. Seed is generally less expensive $30-$40 per acre versus $50 per acre for Hairy Vetch. For early planting, Hairy Vetch will not over winter either. It tends to smother if it is too massive going into winter. Common Vetch may provide nitrogen at a lower price where you want to plant early.
Phacelia is grown on thousands of acres in Europe, but virtually unknown in the US except where it is grown to attract beneficial insects in California. The fine root structure of Phacelia is thought to build soil more quickly than anything else. However, plots at Groff’s were less than impressive. One lesson learned is the seeding rate must be higher. The germination rate is only 50% and so a rate of 10lbs/acre may be more appropriate than the 5lbs/acre we saw. Another caution with Phacelia is it is a host for Sclerotinia. Don’t plant it where you will plant beans.
Groff collected cover crop seed from Europe, Australia, the Midwest and the West to trial alongside old favorites from our area. “The prices for cover crop seed are always fluctuating,” says Groff, “If we can find additional cover crop varieties that do well in our area that will give us greater options if vetch or other seed becomes too expensive.” Combinations and unusual cover crops might also provide additional benefits, such as building soil structure.
A few highlights:
Tillage Radish is a forage radish that Groff grows for seed and promotes for its ability to break up hard pans. The fine roots projecting from a large tap root corkscrew through compacted soil providing a channel for crop roots and water infiltration. Groff’s latest interest is planting radish at a low rate of 2-3 lbs/ acre with wheat. “The word mellow is most popular,” Groff said for soil after radishes or radish small grain combinations.
Indian Head lentil was one experimental legume cover crop Groff planted. He brought it from the Midwest where they love it. “You would think if it grows in North Dakota it would grow here,” Groff said. But in Pennsylvania we have dramatic freeze thaw cycles and Indian Head lentil seems to fail most years. In comparison Early Cover vetch seems to tolerate freeze thaw cycles the best.
Although Common Vetch does not over winter well it may have an important niche. Seed is generally less expensive $30-$40 per acre versus $50 per acre for Hairy Vetch. For early planting, Hairy Vetch will not over winter either. It tends to smother if it is too massive going into winter. Common Vetch may provide nitrogen at a lower price where you want to plant early.
Phacelia is grown on thousands of acres in Europe, but virtually unknown in the US except where it is grown to attract beneficial insects in California. The fine root structure of Phacelia is thought to build soil more quickly than anything else. However, plots at Groff’s were less than impressive. One lesson learned is the seeding rate must be higher. The germination rate is only 50% and so a rate of 10lbs/acre may be more appropriate than the 5lbs/acre we saw. Another caution with Phacelia is it is a host for Sclerotinia. Don’t plant it where you will plant beans.
Subscribe to:
Posts (Atom)
