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 third year of this project was marked in 2007, as on-farm research trials continued from 2006 for three 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 Misera Organic Farm (Steve Misera) was planted in September 2006 with combinations of cover crop species at varying seeding rates. The farmer’s objective is to decrease his dependency of off-farm nitrogen inputs and expand his knowledge of cover crops. We are also comparing seeding rates of five different cover crop combinations for increases in biomass production, competition with weed populations and impacts on subsequent cash crop yields. 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 of pounds per acre (lbs/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 a combination of 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 difference in height and color could be seen in the field.

This trial was followed through the spring of 2007 when aboveground biomass samples of the cover crop plots were taken in May. Each sample consisted of two quadrats from each of the 15 plots. The average aboveground biomass dry matter yields were rye only (3607 lbs/ac), wheat only (3012 lbs/ac), oat-wheat-Austrian winter pea (2783 lbs/ac), oat-wheat-Nebraska hairy vetch (2722 lbs/ac) and oat-wheat-Oregon hairy vetch (2540 lbs/ac).

The cover crop was destroyed in late May and the field was planted into organic field corn with yield data collected. In early September 2007 the field was replanted with three other cover crop combinations. A total of three treatments were used over two replications, in addition to alternation of barnyard manure application in four of the eight plots. The cover crop combinations consisted of rye only (140 lbs/ac), rye-oat-hairy vetch (56 lbs/ac, 38lbs/ac, 30 lbs/ac), rye-oat-Austrian winter pea (56 lbs/ac, 38 lbs/ac,100 lbs/ac). These plots will be sampled in the spring of 2008 for aboveground biomass and the field will again be planted into organic corn.

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 followed the growth of the strawberry 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 leguminous covers and strawberry plantings, project leaders are 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, 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. Biomass dry weights were collected on April 30, 2007 in three treatment plots (rye, red clover & red clover). The results showed aboveground biomass for red clover (3000.3 lbs/ac), rye and red clover (3167.9 lbs/ac), rye (3145.3 lbs/ac). Strawberry plants were planted into these treatment plots in the spring of 2007 and they will be followed through 2008.

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 watermelon and cantaloupe. All covers were planted on September 21, 2006 with a John Deere 450 grain drill and each plot measured approximately 20 feet across (north to south) and 177 feet wide (east to west). The cover crop combinations were planted in 20 foot wide passes per each replication across the field in an east-west direction. There are a total of three cover crop treatments with four replications. 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 was followed through the 2007 growing season, with spring incorporation of the cover crops. The covers were followed by plantings of watermelon and cantaloupes in two successions (early & late). Subsamples of aboveground biomass were taken in each cover crop treatment plot.

Impacts and Contributions/Outcomes

Two field days and one conference workshop were held during 2007 to teach others about the research being conducted on our partnering farms, as well as the value of using cover crops.

The conference workshop was held in February 2007 at the annual Farming for the Future conference sponsored by the Pennsylvania Association for Sustainable Agriculture (PASA). Overall the conference attracted about 1,700 individuals over the course of three days. The presentation entitled “Cover Crop Selection for Weed Control” was well attended by about 180 participants, which is a sizeable number since there was 8-10 other workshop sessions happening concurrently. The presentation included Dave Wilson of the Rodale Institute discussing considerations when selecting a particular cover crop species, what is one hoping to accomplish and what does each of the more often-used cover crops provide when used. Additional presenters included Ron Hoover, On-Farm Research Coordinator with Penn State and Bill Curran, Weed Scientist with Penn State; both discussing fertility considerations, planting depth and cover crop management (rolling, mowing and plowing). This workshop reached a varied audience of full and part time farmers, as well as ag professionals, home gardeners and consumers.

Field days were held in May 2007 at Steve Misera’s farm in Butler, Pennsylvania and at Aimee and John Good’s operation at Quiet Creek Farm/The Rodale Institute. The field day at Misera’s Organic Farm was entitled “Cover Crops and the Diverse Organic Farm.” The field day attracted a total of 20 individuals (excluding the presenters), 15 of which were active producers. 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 cover crop topics discussed at this field day.”

The second field day held at Quiet Creek Farm (on the grounds of the Rodale Institute) attracted 45 participants. The field day entitled “The Rodale Institute: Compost, Cover Crops and Orchards” covered a variety of topics, including the research being conducted by cooperating farmers on this grant, Aimee & John Good. Both the Goods, Dave Wilson of the Rodale Institute and Ron Hoover, On-Farm Research Coordinator at Penn State detailed various topics and research being conducted at the farm. Of the 21 surveys returned, 33% were full time farmers and 95% indicated they were interested in making a change in their current farming rotations to include cover crops and they plan to seek more information on the topic.

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.

Collaborators: