Increased use of cover crops in field and vegetable crop rotations through farmer-directed on-farm research and outreach opportunities

Increased use of cover crops in field and vegetable crop rotations through farmer-directed on-farm research and outreach opportunities

Summary

Visits with numerous farmers in Pennsylvania during the 2004 calendar year revealed many are not aggressively managing their cover crop programs. While many producers incorporate cover crops into production systems, there is still important education to be done concerning the management of these valuable crops. Improved management of cover crops may result in large impacts on weed population dynamics, soil quality, yield of cash crops and ultimately farm sustainability. Producers have been identified who are interested in further developing their knowledge of cover crops and sharing those findings with other farmers. These projects will be designed to conduct on-farm research that will address questions concerning improved production and profitability when cover crops are used in specific situations. Some areas for improving cover crop management include increasing seeding rates, optimizing the time of seeding, and selecting better performing species, especially legumes. Along with project advisors, each cooperating producer will select at least one but not more than two new practices to compare to a standard practice within a replicated study on that farm. As these cooperators increase their knowledge of cover crop management, they will serve as key communicators of their new knowledge to other interested producers in the region.

Objectives/Performance Targets

• Address questions concerning improved production & profitability when cover crops are used in specific situations.

  A particular area of interest will be the impact of cover crop seeding rates on weed management, which has not been well documented in situations where soil fertility might limit crop production.

  Increased education of cover crop management by considering several factors (including but not limited to) seeding rates, timing of planting, method of planting, & selection of cover species.

  Investigation of how improved management can influence weed populations, soil quality, yield of cash crops, farm profitability & sustainability, organic matter & fertility.

  Outreach to other farmers, educators, researchers, etc. to continue to promote the use & proper management of cover crops.

Accomplishments/Milestones

The second year of this project was marked in 2006, as on-farm research trials were developed and some continued from 2005, for all four of our partnering farms. All of these projects are comparing cover crop seeding rates and/or mixes of cover crop species, followed by cash crops.

Trial 1 at Penn Valley Farms began in the fall of 2004 comparing varying rates of cereal rye (biomass data collected), followed by a spring 2005 planting of soybeans (yield & moisture data collected), which was then followed by a fall 2005 planting of winter wheat. Cereal rye is one of the most widely used cover crops in the Northeast. While it provides ground cover that aids in minimizing erosion, it gathers nutrients from deeper in the soil profile and helps with weed control through competition primarily for light. The objective with this trial was to compare two seeding rates of cereal rye cover crop for increases in cover crop biomass and yield of a subsequent soybean crop. A 10’ wide drill was used to create 50’ wide plots that were drilled using one of the two varying seeding rates, which were 2.25 bushels/acre or 3.75 bushels/acre.

Overall establishment of the cereal rye cover was good, but due to some heavy corn stover that remained on the field surface in some areas, rye plant density was reduced in these areas. Aboveground biomass samples were taken of the rye, which was then followed by the soybean cash crop and yields collected. Data indicated that the real limitation to improving cereal rye cover crop stands and biomass yields is the ability to correctly place seed, not seeding rate. While more complete incorporation of residue into the soil should have permitted the drill to do a better job at planting, this is undesirable as fewer residues on tilled fields only worsens the potential for erosion-related losses of soil and nutrients. Use of a heavier drill that is capable of slicing through residue and placing seed at the appropriate depth in the soil should have results in thicker rye stands.

Some benefits of incorporating cover crops into crop rotations are often not immediately visible. While no difference was observed in amount of cereal rye being produced and subsequently added back to the soil in this trial, the expectations are that when growing more cover crop, several benefits will be realized. Among them is that the cover crop will better compete with and reduce weed density and generate more organic matter that will improve soil quality and health. The ability to store more water for following crops, especially during droughty growing seasons, can be especially advantageous.

The farmer cooperator was then interested in using this same field to compare varying seeding rates of small grains. Winter wheat was drilled in October 2005 with two varying seeding rates over five replications. In February 2006 nitrogen effluent from a nearby dairy was spread on the field at a rate of 4,500 gallons/acre. In April 2006 stem counts were conducted on subsamples of the winter wheat (a 3’ length of row) in each treatment plot. Soil samples were also collected at this time. Results showed the comparison of number of stems in each treatment plot with low or high seeding rates was not statistically significant. Although there was a small trend favoring more plants in the higher rate seeded plots. Winter wheat yields (bushels/acre) and moisture data were collected at the time of harvest in 2006. Again these results did not show statistically significant differences in seeding rates. Results of this trial will be compiled in articles and reports for further outreach.

Trial 2 at Shenk Berry Farm is comparing plantings of three varieties of clovers (crimson, mammoth and medium red) at varying seeding rates in combination with sorghum Sudangrass, planted in 2005. In the spring of 2006 a planting of strawberries followed these covers. The objective of the farmer was to test different cover crops to find one he could incorporate into his rotation in effort to decrease off-farm nitrogen inputs. Observations made by the farmer indicated the 2005 growing season was hard on the clover production with heat and drought conditions. The Sudangrass remained standing until the end of November. In the spring of 2006, the field was chiseled and disced in preparation for strawberry planting in late April. Instead of applying more nitrogen when the strawberry crowns were planted, our objective was to see if the plants would show any signs of nitrogen deficiency in the varying plots without added nitrogen. This was in an effort to see if one species of clover contributed to more nitrogen into the soil than another. The plants never showed any signs of deficiency and were visually monitored during the spring and summer of 2006, to ensure no plants were lost due to this trial. In September leaf tissue samples were collected from various plots to monitor their nutrient levels. Unfortunately, the results did not show any statistically significant differences.

We will follow the growth of the plants through the 2007 growing season and based on interest from the cooperating farmer, will also take plant samples to see if leguminous covers may harbor any harmful pathogens detrimental to strawberry production. To further consider this issue, the project leaders are also now working with Dr. Kathy Demchack from Penn State University who works in the field of bramble and berry production. In October 2006 we selected another field to set up a trial to research this issue, which was currently in a stand of red clover. The established red clover cover crop was divided into 8’ wide plots approximately 25’ wide. Only a portion of the field was divided into 3 different treatments (red clover alone, red clover & cereal rye, cereal rye alone). The red clover was rototilled in the treatment areas where only cereal rye was planted. The cereal rye cover crop was drilled into plots (2 bushels/acre) with the existing red clover. Strawberry plants will be planted into these treatment plots in the spring of 2007.

Trial 3 located at Quiet Creek Farm actually began at a previous location, Charlestown Cooperative Farm back in 2004/2005. The growers moved to this new location in southeastern Pennsylvania and agreed to remain engaged with the cover crop research. Currently project leaders are working with the cooperating farmers at this location and the Rodale Institute, who owns the land the farmers are utilizing, to monitor this cover crop trial. The objective is to evaluate winter annual cover crop combinations in rotation before watermelons, cantaloupes and tomatoes. There are three different cover crop treatments at varying seeding rates across four replications. All covers were planted in September 2006. The first treatment used cereal rye (90.5 lbs/ac) and hairy vetch (32.8 lbs/ac); the second treatment used cereal rye (90.5 lbs/ac), hairy vetch (26 lbs/ac), red clover (10.85 lbs/ac); and the third treatment was cereal rye (90.5 lbs/ac), Austrian winter pea (53.8 lbs/ac) and crimson clover (12 lbs/ac). This trial will be followed throughout the 2007 with watermelons and cantaloupes planted in two successions (early & late) and the tomato planting.

Trial 4 at Misera’s Organic Farm was also planted in September 2006 with combinations of cover crop species at varying seeding rates. The farmer’s objective is to decrease his dependency on off-farm nitrogen inputs and expand his knowledge of cover crops. At the time of planting and calibration of the no-till drill used, the field was very soft due to recent rain. These soft soil conditions resulted in the drill calibration being off compared to the original calculations made to figure out the lb/ac ratios. This resulted in the rates used to plant the trial being about 20% greater than intended. A total of five treatments were used over three replications. The first treatment included cereal rye (172 lbs/ac); the second included wheat alone (148 lbs/ac); the third was wheat (148 lbs/ac), oats (47 lbs/ac) and Nebraska hairy vetch (37 lbs/ac); the fourth was wheat (148 lbs/ac), oats (47 lbs/ac) and Oregon hairy vetch (37 lbs/ac); and the fifth was wheat (148 lbs/ac), Austrian winter pea (47 lbs/ac) and oats (123 lbs/ac). Observations of these covers made in early November 2006 indicated that all the covers seemed to be doing well. Two different rye varieties were used and a different in height and color could be seen in the field. This trial will also be followed during the 2007 growing season and subsequent cash crop.

Outreach to facilitate farmer to farmer exchange is a key component to the success of this project, so descriptions and photos of the trials have been added to the PASA website and will continue to be updated as work progresses with plot plans, additional photos and other pertinent information. Already we have begun fielding inquiries and interest in more projects related to cover crop systems in Pennsylvania and neighboring states. As the projects progress and further outreach is done via printed and web-based resources, as well as workshops and field days, we look forward to sharing our results.

Impacts and Contributions/Outcomes

One of the cooperating farms, Shenk Berry Farm hosted a field day in July 2006 entitled “Tools and Methods for Strawberry Production.” A total of 36 individuals (excluding the presenters), 15 of which were active producers, attended the event and results of an exit survey showed increased understanding of various topics presented at the field day. About half indicated they “plan to make a change” in their farming operations as a result of something they learned. Some of these changes included incorporating clover cover crops into their rotations, beginning a weed management program, and learning more about pest and fungus control. Around 60% of those in attendance indicated a desire for more education on these topics in the future and were inspired to “be more active in topics discussed at this field day.”

This field day was in addition to one held in 2005 entitled “Cover Cropping to Improve Soil Quality, Manage Weeds and Improve Production” reported on in last year’s annual report. Additional field days and farm tours are being planned for 2007 at two other partnering farm locations where we hope to reach approximately 30-40 producers and interested parties. The 2007 PASA Farming for the Future conference will also be host to a workshop entitled “Cover Crop Selection for Weed Control and Soil Quality” where we hope to reach an audience of 50-60 participants. These events will aid in further outreach to farmers, educators, conservation program planners and others with an interest in promoting an increase usage of cover crops and understanding the best methods to employ.

Collaborators: