California Ag Network

Category: Non-Video

  • Do Ladybugs Help Your Garden Grow? Depends On Surroundings

    When cabbage looper moth larvae infest a field, sustainable growers will often try to control the pests by releasing large numbers of predators, such as ladybugs. That way they can avoid spraying expensive and environmentally harmful insecticides.

    Still, farmers have mixed results when they supplement their fields with beetles or other predators.

    Cornell impacting New York State

    A new study of cabbage crops in New York – a state industry worth close to $60 million in 2017, according to the USDA – reports for the first time that the effectiveness of releasing natural enemies to combat pests depends on the landscape surrounding the field.

    “The landscape context can inform how to better use this strategy in field conditions,” said Ricardo Perez-Alvarez, the paper’s first author and a graduate student in the lab of co-author Katja Poveda, associate professor of entomology. Brian Nault, an entomology professor at Cornell AgriTech, is also a co-author.

    The paper, “Effectiveness of Augmentative Biological Control Depends on Landscape Context,” was published June 17 in the journal Nature Scientific Reports. It showed that releasing pest predators led to fewer pests, less plant damage and increased crop biomass on farms surrounded by more forest and natural areas and less agricultural land. But on farms predominantly surrounded by other farms, the reverse was true, with more pests and plant damage and reduced crop biomass in spite of added predators.

    The reasons behind this phenomenon are complex, and depend on interactions between local predators and those that are added, which can vary on a case-by-case basis. The predators in primarily agricultural landscapes may be less diverse and may then attack the same pests, increasing the potential for competition and negative interactions. Predators also have fewer microhabitats (small-scale physical requirements of an organism or a community of organisms), which can intensify the competition for space and diet.

    Simple agricultural landscapes can also increase the likelihood that one predator species will prey on another predator species. For example, smaller predators become vulnerable to larger predators, which then affects the collective effect of multiple predators on pest control.

    “Landscape composition influences how predator species interact with one another and thereby mediates the potential consequences for biological pest control,” Perez-Alvarez said.

    A spined soldier bug nymph and a cabbage looper larvae on a cabbage plant.

    The study focused on cabbage crops and three cabbage pests (the larvae of the cabbage white butterfly, the diamondback moth and the cabbage looper moth), and their natural enemies. In central New York, there are 156 native predator species and seven parasitoid wasps that prey on these pests. Among these, two generalist predators are commonly used to augment fields with additional pest enemies: the spined soldier bug and the convergent ladybird beetle. These two generally complement each other well because soldier bugs feed on larvae and ladybugs feed on eggs.

    In the study, the researchers set up experimental plots on 11 cabbage farms in central New York, which together represented a range of surrounding landscapes from agricultural lands to natural areas.

    Each farm had two cabbage plots: one that was left alone so it was exposed to the naturally occurring predators, and another where soldier bugs and ladybugs were added. The researchers then collected a wide range of data that included surveys of pest and predator abundances, plant damage and final crop yields. They also conducted lab experiments to better understand the relationships between predators and how those interactions impact pest control.

    Given how complex these predator-predator and predator-pest interactions and their relationships to pest control can be, more study is needed to make specific recommendation to growers. Still, the paper is a first step toward understanding how landscapes influence the effects of augmenting farms with predators for pest control.

    The study was funded by National Institute of Food and Agriculture at the United States Department of Agriculture.

    By Krishna Ramanujan

  • Creating A Safe, Clean Home For Stockpiled Almonds

    Once harvest kicks off, stockpiles of in-hull almonds become a favorite spot for Aspergillus mold as the moisture in almonds, combined with larger swings in air temperature from day to evening, result in elevated moisture levels and create a hospitable environment for the damaging mold to thrive.

    Aspergillus mold produces aflatoxin that causes significant food safety concerns that can put export shipments at risk as there are stringent maximum limits for aflatoxin contamination in key markets. High moisture levels in stockpiles can also lead to black mold on hulls and concealed damage of kernels – a condition in which nuts develop off-color and off-flavors after roasting.

    Proper moisture control before stockpiling, and regular monitoring and adjusting of moisture levels in stockpiled almonds can help to limit the amount of moisture build-up and prevent these issues. Prior to stockpiling, field samples should be taken either before sweeping or in the windrow. Because there can be great variability in the moisture levels of crop that is drying on the ground, growers should sample from areas where the moisture content is likely highest. The highest moisture levels prior to sweeping can typically be found in almonds on the north side of the canopy next to the trunk. For windrows, moisture levels are higher in the bottom layer of almonds. Moisture content for almonds should be below 6% for the in-shell kernel, less than 9% for the total fruit (in-hull almond) and less than 12% moisture content for hulls. If moisture exceeds these recommended levels, growers should hold off on stockpiling and take the crop to a dry area where the nuts can be turned and spread to reduce moisture. Machine drying is also an option.

    Once almonds are ready for stockpiling, the orientation and shape of the stockpile plays an important role in moisture management. Stockpiles should be placed on a firm surface in an area that encourages optimal drainage – either with a raised or sloped bottom. Creating drainage channels can further prevent water or rain from affecting stockpiles. Since condensation and mold growth are typically worse on the north end of a pile, it’s recommended to position the long side of the stockpile on a north-south axis to minimize that effect. Finally, one should ensure that each stockpile has an even, flat top to reduce the number of areas where condensation can build up on the underside of the tarp.

    With stockpiles in place, hullers/shellers should implement proper management practices to keep moisture in check. While covering stockpiles with tarps is important, tarp selection is just as important to keep humidity minimized. White-on-black tarps work best as they minimize temperature fluctuations. Clear tarps allow the greatest temperature fluctuations, but are fine to use on dry, in-hull almonds that are below the moisture threshold. And white tarps fall somewhere in the middle in terms of their ability to minimize temperature fluctuations. When ongoing moisture monitoring indicates that moisture levels are too high, hullers/shellers should open up the tarps during the day to allow moisture to escape and cover again at night.

    Additionally, it’s important to manage trash, dust and other potential contaminants, particularly pests like insects and rodents who can spread bacteria such as Salmonella and E. coli. When disease-carrying pests are found they should be treated, as needed, keeping detailed records if fumigants are used.

    The Almond Board of California (ABC) is committed to continued research into best practices around almond storage and processing. You can learn more about stockpile management in ABC’s “Stockpile Management Best Practices” guide. This resource provides valuable information on creating and managing stockpiles in ways that help our industry deliver a safe, high-quality product to the U.S. and around the world.

  • Successful Hullsplit Requires Thoughtful Irrigation, Nutrient Management

    While the onset of hullsplit signals that harvest season is near, it also marks the start of an unwelcomed orchard guest: hull rot. Almond hulls are susceptible to hull rot fungi from the beginning of hullsplit until the hulls dry, which is typically a month long, though the period may vary depending on fertilization and irrigation. Successful hull rot control is based upon effective strategic deficit irrigation and nitrogen management.

    Strategic Deficit Irrigation

    Strategic Deficit Irrigation (SDI) is the practice of stressing almond trees at specific crop stages to reduce water use without impacting crop productivity. By managing SDI, growers can reduce hull rot by 60–90% and experience a more uniform hullsplit and earlier harvest. These factors may contribute to less crop damage from weather, late-season NOW flights and aflatoxin contamination.

    The target period for stressing trees is from the start of hullsplit through 90% hullsplit, a period of about two weeks. The most accurate way to implement SDI is to use a pressure chamber to track and maintain slight tree water stress levels, between -14 bars and -18 bars, depending on the weather. Watch a short video from the Almond Board of California (ABC) about how to use a pressure chamber here.

    Growers who do not rely on pressure chambers, particularly those with a history of hull rot and a visual baseline from which plant stress can be observed, may achieve similar results by irrigating at 50% of normal tree demand, using crop evapotranspiration (ETc) calculations during hullsplit. More information about this strategy is available at the UC Almond Doctor’s website.

    Hullsplit typically occurs at the beginning of July in the early growing seasons and spreads to later growing seasons accordingly. However, onset of hullsplit can vary according to orchard conditions, with stress levels varying based on soil type and other factors. In shallow soils where trees may dry quickly, growers should initiate stress when blanks start to split, usually about a week before the onset of hullsplit. On deeper, well-drained soils, it can take up to 20-to-30 days to reach mild-to-moderate stress levels. In this case, growers may want to use the UC Almond Hull Split Prediction Model to determine when to initiate water stress. More information about the fundamentals of strategic deficit irrigation are explained in this short ABC video here.

    Nitrogen Management

    Almond Board-funded research has found that excessive nitrogen increases incidences of hull rot. It is critical that a proper nitrogen budgeting plan is in place for the growing season to ensure that only the necessary amount of nitrogen is applied. It is important to follow the nitrogen budgeting plan throughout the growing season, which is a function of crop load.

  • John Deere Announces New Registered Apprenticeship Program

    John Deere has received approval from the U.S. Department of Labor for its new Registered Apprenticeship Program and is making it available to its Agriculture & Turf and Construction & Forestry dealers. The program will help address a widespread shortage of service technicians, especially in rural areas across the country, by providing dealers with a formalized, on-the-job and technical training plan to help them develop more highly skilled employees.

    “The new Registered Apprenticeship Program complements our existing John Deere TECH program,” said Grant Suhre, director, region 4 customer and product support for John Deere Ag & Turf. “In addition to the on-the-job training experience, an apprentice will receive technical instruction and be assigned a personal mentor as a part of the highly organized training structure. Upon completion of the apprenticeship, he or she will receive a nationally recognized journeyworker certificate.”

    Through participation in the apprenticeship program, dealers formally commit to developing additional talent in an earn-while-you-learn program. A participating apprentice benefits from structured, on-the-job training in partnership with an experienced mentor. As training progresses, apprentices are rewarded for new skills acquired. According to Tim Worthington, manager, customer support for the John Deere Construction and Forestry Division, participating dealerships will see numerous benefits.

    “Because of the earn-while-you-learn nature of the program, it will help dealers more easily recruit new employees and further develop a highly skilled workforce,” Worthington said. “This can improve a dealer’s productivity and profit potential as employee turnover costs are reduced and employees are retained longer. In addition, John Deere customers benefit from access to more highly skilled dealer personnel who are servicing or supporting their equipment.”

    John Deere dealers can collaborate with any number of local organizations as part of the Registered Apprenticeship Program. These organizations include, but are not limited to, the John Deere TECH Program, K-12 schools, community colleges, labor organizations, economic development groups, foundations and workforce development boards. John Deere dealers who wish to participate can receive support and technical assistance from John Deere and JFF (Jobs for the Future, a U.S. Department of Labor intermediary), who will expedite the registration process with their state or federal apprenticeship agency. After registering, dealers can immediately enter employees into the Agriculture and Equipment Technician or Heavy Construction Equipment Mechanic programs. In addition, they can select other occupations for the apprentice program, including sales professionals, parts professionals, accountants or many other occupations and develop appropriate work processes for those jobs. Next, dealers will identify master-level employees who are capable of and willing to mentor apprentices. Finally, dealers will identify potential candidates or incumbent workers who would benefit from the apprenticeship program and enroll them.

    When apprentices participate, they track and report their on-the-job learning and technical training time in conjunction with their employer. The dealer’s program administrator then inputs this data into the appropriate state or federal database. To ensure high standards are maintained, dealers are required to follow specific guidelines, developed over years of apprenticeship experience, after they are registered.

    To simplify participation for its dealers, John Deere created national guideline standards for the Registered Apprenticeship Program, which have been shared with its dealer channel and is providing technical assistance to dealers interested in participating. “These guidelines provide a consistent apprenticeship program template that any dealer can implement if they participate,” Suhre explained. Dealers can utilize these national guideline standards to have a program approved and operating in a very short timeframe.

    For more information about the John Deere Registered Apprenticeship Program, please visit your local John Deere dealer.   Deere & Company (NYSE: DE) is a world leader in providing advanced products and services and is committed to the success of customers whose work is linked to the land – those who cultivate, harvest, transform, enrich and build upon the land to meet the world’s dramatically increasing need for food, fuel, shelter and infrastructure. Since 1837, John Deere has delivered innovative products of superior quality built on a tradition of integrity. For more information, visit John Deere at its worldwide website at www.JohnDeere.com.

  • Purdue Professor Helps Longtime Grape Growers Embrace New Technology

    California vineyard owners are carefully watching grapes mature on the vine this summer, just one in a list of responsibilities that determines their chances at a successful season.

    Years of experience working the land have been the main tool for these growers, but environmental restrictions and requirements are making the job increasingly complicated.

    David Ebert of Purdue University’s College of Engineering is focused on helping the wine industry through Discovery Park’s Big Ideas program. Ebert along with Christian Butzke, a food science professor and enologist, and other Purdue colleagues are trying to help growers in California transition to utilizing new, efficient technology for their operations without being caught in a data overload.

    “We’ve basically been looking at factors in how the growers can harness technology that allows them to become more effective and more efficient in their operations and decision making,” said Ebert, Purdue’s Silicon Valley Professor of Electrical and Computer Engineering.

    There are long-running farm owners who are only now beginning to consider the new technologies available to them.

    “Since it hasn’t been made intuitive to use and they haven’t grown up using it, they are uncomfortable blindly trusting what a computer is telling them to do, and they shouldn’t have to be,” Ebert said. “They need tools to make data understandable and useful to them in their operations.”

    Because grapes are a perennial crop, some decisions by growers can have a 20- to 25-year impact on their operations and their profitability. Ebert’s work is intended to help growers understand how to make effective decisions in adopting new technology to increase their economic and ecological sustainability. The technology is intended to improve both day-to-day and long-term operations as well as help their overall investment.

    Ebert said growers today are facing new local community constraints in addition to uncertain growing season conditions. A number of counties in California have decided vineyards need to be certified sustainably farmed and many ground water districts are setting new guidelines to preserve water resources and make sure that water is used effectively.

    “Trying to bring all of those factors together is a complex process,” Ebert said. “We’re working to bring all these limitations and data together in a understandable system so people have the policy constraints, economics, science basis, data analytics and their operations models combined into a simple dashboard to make better decisions.”

    When the project began in 2014, Ebert discovered that the rules of thumb many growers used to judge crop conditions no longer worked. Data collected from the technology can help forecast and understand multi-year impacts on the crop, including complex weather.

    “There’s an increasing trend for growers wanting these new tools, seeing real value in it and realizing that they need to move in this direction to be sustainable economically and environmentally,” Ebert said.

    However, the technology and data must be targeted to each crop and regional conditions to be trustworthy and effective. Ebert said technology that works for wheat farms in Kansas can’t be directly translated to work for a vineyard crop that has been growing for 20 years.

    “Some vineyards we work with were planted in the early 1900s,” he said. “These vines are adaptable, but the growers need the right information in these unprecedented growing conditions.

    “This is what our Purdue science-based, data-driven and grower-driven approach enables: Understandable, trustable information from all these new sensors and data sources to enable them to adapt and sustain their operations.”

  • Agricultural Leaders Announce Support For USMCA

    Agricultural leaders around the Central Valley announced their support for the United States-Mexico-Canada Trade Agreement, referred to as the USMCA and call upon Congress to act quickly and to vote on the agreement.  The USMCA would replace the 1994 North American Free Trade Agreement (NAFTA) and offers Agricultural more opportunities.

    The Agricultural Industry plays a vital role in California’s economy. California produces and grows the safest food in the world. In 2017 – 2018, 77,100 farms and ranches in the state, received a total of $50.13 billion for their commodities. Agricultural exports in 2017 were $16.8 billion to Canada and $26.8 billion to Mexico for a total of $43.6 billion.

    The ability to export, assures California will continue to remain the leading state in our nation for agricultural commodities.  The USMCA would continue to expand our exports into both Mexico and Canada, which would ensure more economic growth in California, providing more jobs and resources to our state.

    We believe that the USMCA would better serve the interests of American workers, businesses, farmers, ranchers and would help us continue our long-term good relationships with both Canada and Mexico.

    It is important for our California Congressional members to stand with our industry and encourage Congress to vote before summer recess and pass the USMCA.

    Signed by the following organizations:

    Nisei Farmers League, African-American Farmers of California, Tulare County Farm Bureau, California Apple Commission, California Blueberry Commission, Olive Growers Council of California, Stanislaus County Farm Bureau, Milk Producers Council, Merced County Farm Bureau

  • USDA Now Making Payments for New Dairy Margin Coverage Program

    The U.S. Department of Agriculture’s Farm Service Agency (FSA) opened enrollment for the Dairy Margin Coverage (DMC) program on June 17 and has started issuing payments to producers who purchased coverage. Producers can enroll through Sept. 20, 2019.

    “Times have been especially tough for dairy farmers, and while we hope producers’ margins will increase, the Dairy Margin Coverage program is providing support at a critical time for many in the industry,” said Bill Northey, USDA Under Secretary for Farm Production and Conservation. “With lower premiums and higher levels of assistance than previous programs, DMC is already proving to be a good option for a lot of dairy producers across the country.  USDA is committed to efficiently implementing the safety net programs in the 2018 Farm Bill and helping producers deal with the challenges of the ever-changing farm economy.”

    Authorized by the 2018 Farm Bill, DMC replaces the Margin Protection Program for Dairy (MPP-Dairy). The program offers protection to dairy producers when the difference between the all-milk price and the average feed cost (the margin) falls below a certain dollar amount selected by the producer. To date, nearly 10,000 operations have signed up for the new program, and FSA has begun paying approximately $100 million to producers for January through May. 

    May Margin Payment

    DMC provides coverage retroactive to January 1, 2019, with applicable payments following soon after enrollment.

    The May 2019 income over feed cost margin was $9.00 per hundredweight (cwt.), triggering the fifth payment for eligible dairy producers who purchase the $9.50 level of coverage under DMC. Payments for January, February, March and April also were triggered.

    With the 50 percent hay blend, FSA’s revised April 2019 income over feed cost margin is $8.82 per cwt. The revised margins for January, February and March are, respectively, $7.71, $7.91 and $8.66. 

    Coverage Levels and MPP Reimbursements

    Dairy producers can choose coverage levels from $4 up to $9.50 at the time of signup. More than 98 percent of the producers currently enrolled have elected $9.50 coverage on up to 95 percent of their production history.

    More Information

    On December 20, 2018, President Trump signed into law the 2018 Farm Bill, which provides support, certainty and stability to our nation’s farmers, ranchers and land stewards by enhancing farm support programs, improving crop insurance, maintaining disaster programs and promoting and supporting voluntary conservation. FSA is committed to implementing these changes as quickly and effectively as possible, and today’s updates are part of meeting that goal.

    For more information, visit farmers.gov DMC webpage or contact your local USDA service center. To locate your local FSA office, visit farmers.gov/service-locator

  • Tulare County Crop Report (For the Week Ending: July 20, 2019)

    Small Grains, Other Field Crops:

    Corn for silage continues to mature. Black-eyed beans continue to mature. Cotton continues to be irrigated and cultivated. Alfalfa continues to be cut and baled.

    Deciduous Tree Fruit, Nuts, And Grapes:

    The stone fruit season continues on. Peaches are being exported to Canada, Taiwan, Costa Rica,Mexico, El Salvador, Panama, and Chile. Nectarines are being exported to Mexico, Canada, Costa Rica, and Chile. Plums are being exported to Canada, Taiwan, China, Costa Rica, and Australia. Apricots are being exported to Canada. Hand-pruning and mechanical topping continues to take place in some stone fruit orchards, after harvest. Immature stone fruit continues to develop.

    Some older stone fruit groves are being removed after harvest. Grapes continue tomature and harvest has now slowly begun. Grapes are being exported to Japan, Korea, thePhilippines, and Thailand. Some vineyards continue to have leaves thinned to allow for betterairflow and light. Irrigation continues for grape vineyards. Almond, pecan, walnut, and pistachionuts continue to develop. Pistachios are being exported to Hong Kong, Spain, Costa Rica, Vietnam, and Turkey. Almonds are being exported to the Dominican Republic, Costa Rica,Belgium, Japan, Vietnam, Brazil, Colombia, Finland, and Mexico. Persimmons continue todevelop. Irrigation continues for nut and stone fruit orchards.

    Citrus, Avocados, And Olives:

    Valencia and navel oranges continue to be harvested. Late navel harvest is nearing the end, withoranges being sent to domestic markets only. Gassing of Valencia oranges to improve color continues. Valencia oranges are mainly being sent to domestic markets, but they continue to beexported in small amounts to Mexico, Taiwan, Malaysia, Singapore, and Korea. Ruby Grapefruitare being exported to Mexico. Finger limes continue to be exported to France and theNetherlands. Some citrus groves are being pruned and hedge rowed. Navel oranges are being harvested for juice from the field. Immature olives continue to develop.

    Vegetables, Melons, Herbs, Berries:

    Certified producers are picking tomatoes, peppers, eggplant, cucumber, watermelon, and squash. Summer vegetables continue to be sold at roadside stands and Farmer’s Markets. Strawberries, blueberries, and raspberries are being picked and sold by local growers. Blueberries are beingexported to Japan, Taiwan, and the Netherlands.

    Livestock And Poultry:

    Rangeland forage is of good quality. The fed cattle price is at $110 per cwt.

    Additional Comments:

    Local wholesale nurseries are still shipping small orders of nursery stock to local and out-of-state retail nursery outlets. Nurseries continue to receive new rootstocks of various flowers and plants daily. Bare-root rose shipments continue to be sent to Florida.

     

  • Drones Provide Eye-in-the-Sky to Help Fight Fires

    Wildfires blackened nearly 8.8 million acres in the United States last year, highlighted in the news by California’s Camp Fire, the deadliest in that state’s history.

    One of the many things that make wildfires so difficult to contain is the effect a fire has on local winds, which can move the fire in unexpected directions with virtually no notice. But, now, technology is being tested that may help firefighters keep pace with a blaze – increasing their safety and allowing them to better position their limited resources.

    Xiaolin Hu, director of Georgia State University’s Systems Integrated Modeling and Simulation lab, is heading a project that develops drones to collect real-time data about wildfires, including fire front data and wind data in the wildfire area. USDA’s National Institute of Food and Agriculture is funding the project.

    “Fires generate heat that can have a major impact on local wind/weather conditions,” Hu said. “The constant interaction between fire and atmosphere causes dynamic and local changes in wind speed and direction that are not predicted well by standard weather models or expert judgment. The real time data collected by [drones] can help firefighters by providing fire location and fire spread information – and issue an “early warning” to firefighters if they are in danger.”

    Hu and research partners Haiyang Chao, director of the University of Kansas’ Cooperative Unmanned Systems lab, and Ming Xin, professor of mechanical and aerospace engineering at the University of Missouri, are testing their “KHawk” drone over prescribed fires, and building new drones for autonomous sensing, navigation, and control. The new aerial platform features autopilot, thermal camera, and other specialized avionics.

    The drones will perform test flights over prescribed fires ranging from 20 to 300 acres every year until 2022 to collect data on fire propagation and fire generated wind. The team is also seeking opportunities to collaborate with Kansas/Missouri Forest Service to fly over non-prescribed wildfires.

    The drones will fly autonomously, given real-time wind/fire data and predicted fire spread information, under the supervision of human pilots and control station operators on the ground.

    “The ultimate goal is to support the decision making of fire managers and improve safety for firefighters on the ground,” Hu said. “An important aspect of this project is to develop collaboration where fire managers and firefighters work together with drones in collaborative tasks.”

    NIFA invests in and advances agricultural research, education, and extension and seeks to make transformative discoveries that solve societal challenges.

  • ‘Planting Green’ Cover-Crop Strategy May Help Farmers Deal With Wet Springs

    UNIVERSITY PARK, Pa. — Allowing cover crops to grow two weeks longer in the spring and planting corn and soybean crops into them before termination is a strategy that may help no-till farmers deal with wet springs, according to Penn State researchers.

    The approach — known as planting green — could help no-till farmers counter a range of problems they must deal with during wet springs like the ones that have occurred this year and last year. These problems include soil erosion, nutrient losses, soils holding too much moisture and causing a delay in the planting of main crops, and main-crop damage from slugs.

    “With climate change bringing the Northeast more extreme precipitation events and an increase in total precipitation, no-till farmers especially need a way of dealing with wet springs,” said Heather Karsten, associate professor of crop production ecology, whose research group in the College of Agricultural Sciences conducted a three-year study of planting green. “We wanted to see if farmers could get more out of their cover crops by letting them grow longer in the spring.”

    Cereal rye cover crop that was killed with glyphosate herbicide three weeks prior (left) and that will be killed after soybean planting. IMAGE: HEATHER KARSTEN/PENN STATE

    As cover crops continue to grow, they draw moisture from the soil, creating desired drier conditions in wet springs for planting corn and soybeans. With planting green, after those main crops are planted into the cover crops, the cover crops are typically terminated by farmers with an herbicide. The decomposing cover crop residues then preserve soil moisture for the corn and soybean crops through the growing season.

    The study took place at five sites over three years — on three cooperating Pennsylvania farms that plant no-till in Centre, Clinton and Lancaster counties; at Penn State’s Russell E. Larson Agricultural Research Center in Centre County; and at the University’s Southeast Agricultural Research and Extension Center in Lancaster County.

    At each location, researchers compared the results of planting green to the traditional practice of terminating cover crops 10 days to two weeks before planting the main crops of corn and soybeans.

    Cover crops included in the study were primarily rye and triticale, as well as a mixture of triticale, Austrian winter pea, hairy vetch and radish in one location.

    Lead researcher Heidi Reed, a doctoral degree student in agronomy when the research was conducted, who is now an educator with Penn State Extension, inspects a corn field that was part of the study. Corn on the left side of the photo was planted green; the right side was a “control” treatment, with the cover crop killed 14 days prior to corn planting. IMAGE: HEATHER KARSTEN/PENN STATE

    Findings of the research, recently published online in Agronomy Journal, were mixed, according to study leader Heidi Reed, a doctoral student in agronomywhen the research was conducted who is now an educator with Penn State Extension, specializing in field and forage crops.

    Reed noted that planting green appeared to benefit soybean crops more than corn.

    Planting green increased cover crop biomass by 94 percent in corn and by 94 to 181 percent in soybean.

    However, because planting green results in more cover crop residues acting as mulch on the surface, it also cooled soils from 1.3 to 4.3 degrees Fahrenheit at planting.

    At several of the sites during the study years, main-crop plant populations were reduced when planted green, possibly due to the cooler temperatures slowing crop emergence and nutrient cycling, and/or from cover crop residue interference with the planter. In corn, in a few cases, crop damage by slugs was also increased when corn was planted green.

    A slug perches next to a soybean seedling showing slug damage in a field at Penn State’s Southeast Agricultural Research and Extension Center in Lancaster County. IMAGE: HEIDI REED/PENN STATE

    No-till farmers struggle with slugs damaging corn and soybean seeds and seedlings because no-till doesn’t disturb the soil and kill slugs or bury their eggs the way tillage does.

    “No-till with cover crop residues also provides habitat for some crop pests and keeps the soil moist — so no-till cover crop systems tend to be great slug habitat,” Karsten said.

    “We had hoped that letting cover crops grow longer in the spring would supply alternative forage for the slugs, as well as habitat for slug predators such as beetles — and these factors would reduce slug damage of the main crop seedlings. But we did not see a consistent reduction in slug damage on main crops as we expected.”

    When researchers compared crop-yield stability between the two cover crop termination times across the multiple locations and years, corn yield was less stable and reduced by planting green in high-yielding environments; however, soybean yield was not influenced by planting green.

    “We concluded that corn was more vulnerable to yield losses from conditions created by planting green than soybeans, ” Reed said. “Since soybean yield was stable across study locations, and not affected by cover crop termination date, we suggest that growers who want to extend cover crop benefits and avoid the risk of crop-yield reduction from planting green should consider trying it first with soybean.”

    Also involved in the research were William Curran, professor emeritus of plant science; John Tooker, professor of entomology; and Sjoerd Duiker, professor of soil management and applied soil physics.

    Northeast Sustainable Agriculture Research and Education and the U.S. Department of Agriculture’s National Institute of Food and Agriculture supported this research.

    By Jeff Mulhollem