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On June 04, 2020

To Consider Planting Green This Year

Most of the state has received well above average rainfall in the last month  with half of that falling just last week in some locations. Excess moisture plus cool temperatures in April have delayed field work, including planned cover crop burndowns. Meanwhile, cover crops continue to grow, with rye heads emerging and crimson clover starting to bloom in the southeast. 

Those who did have the chance to burn down cover crops may notice the dead residue insulating the soil—this is excellent for soil conservation, traps excess moisture and slows evaporation, so soil takes longer to dry enough to be suitable for corn and soybean planting. According to the Penn State Agronomy Guide, optimum corn grain yield declines by about one bushel per acre per day delayed after the ideal planting window, which ranges from mid-April to mid-May in longer-and shorter-season parts of the state, respectively. Risk of delayed planting causing yield loss in soybeans is lower, as full-season soybeans can still reach full yield potential through mid-May. 

Extension Agronomist Heidi Reid explains with the clock ticking on optimum planting time in the southeast and some more rain in the forecast, planting green could be a viable option for growers concerned with the size and maturity of their cover crops, and itching to get in the field. 

Penn State research has shown that planting green into living cover crops provides a significantly drier seed bed compared to planting into cover crops killed a week or more pre-plant. Allowing the cover crops to grow until main crop planting means they continue to transpire, drawing water from the root zone and drying the soil. Planting green can also conserve more moisture later in the growing season compared to pre-plant killed cover crops, due to the higher biomass residue trapping moisture. 

One reason many farmers plant green for the first time is time and weather constraints, or ineffective herbicide applications. So, even if you did not plan on planting green this spring, conditions are right to give it a try. As with any new management practice, it is best to do some homework before using it on all your acres.

Based on our 3 year, 5 site research project, we have come up with some suggestions for successful planting green. This abridged list includes only those applicable now and throughout this growing season, although best management truly begins in the fall before cover crop planting.

Start planting green with soybeans instead of corn. Soybeans adapt to reduced populations from residue interference and cooler soils by branching, compared to corn which cannot adapt to reduced populations. Additionally, slowed release of nitrogen tied up in the cover crop due to high C:N mature cover crops and cooler soil is not a concern for soybeans, compared to corn.

Consider how much cover-crop biomass your equipment can handle, and rolling/crimping mature, high-biomass covers. Though every farmer uses different equipment and settings for planting green and management varies farm-to-farm, all equipment should be well maintained and calibrated. We recommend rolling cover crops taller than 18 inches to reduce cover crop residue interference with the main crop.

Use aggressive row cleaners to start. This is often a matter of preference, but those new to the practice may appreciate more aggressive residue management for better sunlight penetration to help warm the furrow and improve emergence.

Use a planter rather than a drill for establishing soybeans. Greater precision with planters improved soybean performance compared to drills when we planted green.

Focus on optimum planting depth. Planting green can result in planting through significantly more biomass than usual. Make sure to adjust gauge wheels to account for the thickness of the extra residue. 

Carefully attend to nitrogen management with corn, including at planting and sidedress N as needed. To make sure the corn doesn’t suffer from the slow release of N from high C:N mature cover crops, an extra 50 pounds per acre of N at planting is advised, with the remainder of N needs applied at side-dress based on yield goals. PSNT and tissue sampling can help dial in N needs.

Scout for early season pests and use of IPM to manage pests. Scouting for pests and using integrated pest management practices are always considered best practices.

Avoid neonicotinoid seed treatments and pre-emptive insecticide sprays that can kill predators of insect and slug pests, which are allies in pest control. Some farmers have found that planting green reduces slug damage to their main crops; we found that reduced slug damage was not predictable in soybeans and found mixed results for corn but promoting natural enemies has been shown in other studies to significantly reduce pests.

Finally consult with farmers in your area who have planted green successfully. It is always best to learn from those nearby with similar soils and crop rotations who have planted green successfully. Do not be afraid to ask questions and learn from others’ mistakes. 

To Seek Information On Financial Relief Opportunities Related To COVID 19

The Penn State Business Management Team maintains a website with resources for small farm and food businesses. This information includes the various financial relief opportunities for the COVID-19 virus. The information is constantly updated and will help you decide which programs you may qualify for and how to make an application.  For more information visit the following website: – https://extension.psu.edu/emergency-actions-for-small-farm-and-food-businesses-in-response-to-covid-19 

For additional Covid-19 Resources go to The Penn State Small Business Development Center Emergency Capitol Programs and Resources;  https://sbdc.psu.edu/resources/covid-19-resources/ 

Quote Of The Week: Think twice before you speak, because your words and influence will plant the seed of either success or failure in the mind of another. Napoleon Hill