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Avoiding Herbicide Carryover

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  With a new year coming, farmers are buying inputs for next years crops. Now is the time to think about purchasing herbicides, but also think about how to avoid herbicide carryover, especially if planting cover crops. Factors that increase herbicide carryover include dry weather, late application especially on herbicides with long half-lives, low soil microbial activity, low soil organic matter (SOM), and cooler and cloudy days. Soil texture (especially sandy soils with low SOM) and soil pH also affect herbicide breakdown. In soybeans, there are five major types of herbicides to watch to avoid herbicide carryover. Flexistar/Reflex and Warrant Ultra (fomesafen) soybean herbicides have a long half-life with up to 18 months planting restriction for small seeded legumes and clovers, brassicas (radish, kale, rape), and even some grasses (oats 4-18 months, rye, wheat, barley 4-11 months). The mode of action is a Group 14 which is a PPO inhibitor (causes reactive oxygen). Authority, Optill,

Planting Small Seeded Clovers and Legumes

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Planting small seeded clovers and legumes can be challenging, be that for forages or as a cover crop. Soil types, surface residue, weather especially moisture, seeding depth and getting the right rate on can all either cause a failure or a reduced stand. Here are a couple planting tips. Small seeded clovers and legumes can grow well in sandy loam soils to clay soils with some modifications. Sandy soils tend to dry out and the seed may move too deep in the soil at planting. On clay soils, the soil may be more compacted but they tend to hold more moisture. If the seed stays to close to the surface, without adequate rain, the seed may dry out or get tied up in a thick crust. Often a nurse crop (oats) may help small seeded crops emerge and also initiate critical microbes that can assist a small seedling in germination and growth. Most clovers and legumes need a good pH and lime (calcium carbonate) or gypsum (calcium sulfate) to have good germination. Adequate calcium is needed to initiate

Cover Crop or Cash Crop?

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  Cover crops protect the soil, build organic matter, and promote healthy soils. Some cover crops are used as forages (sorghum, triticale, and clovers) while others are used for grain (barley, milo, oats, wheat, rye). Now a winter cover crop (winter pea) has been bred for human food and another (penny cress) for oil. Several winter cover crops may now offer farmers additional cash while providing environmental benefits.  USDA-Agricultural Research Service (ARS) has been researching winter or autumn-sown peas (Pisum sativum) also called "black peas" or "field peas” which are annual legumes with excellent nitrogen-fixing abilities. These pea species originated in the eastern Mediterranean and western Asia. They should not be confused with cowpeas (Vigna unguiculata), a summer annual which are also known as field peas. Winter peas have been traditionally grown as a cover crop to generate nitrogen, used as animal feed, or used in wildlife plots. Now winter peas (WP) have bee

Manure Benefits Soil Health

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  Manure is a great fertilizer for improving soil health, commonly used before commercial fertilizer. If manure is applied correctly, using the 4R’s (right source, right rate, right time, right place) and proper best management practices, manure greatly improves crop growth and also increases biological activity, leading to improved soil health. Some of the environmental benefits include: increasing soil carbon and reduced atmospheric carbon, reduced soil erosion and runoff, reduced nitrate leaching, and reduced demand for commercial nitrogen fertilizer derived from natural gas. Manure increases soil organic matter because it has nutrients plant require for adequate growth (N-P-K, micronutrients), so plants grow better and faster, producing more roots and crop residue to build soil carbon. Manure consists of carbon residues which the plants can use in the form of carbon dioxide for increased photosynthesis. Adequate soil carbon is limiting plant growth, so manure and carbon may boost p

Fertilizer Stratification

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  Fertilizer stratification occurs when a farmer surface apply soil nutrients like phosphorus (P) and potassium (K) without doing any tillage. Deep tillage (plowing 6-8 inches deep) generally moves and mixes surface applied nutrients down about 3-4 inches, or roughly 50%. Some farmers worry that nutrients applied at the surface will not be plant available. Marion Calmer, an experienced no-till farmer and researcher in Illinois, found that roughly 54% of his P and 43% of his K was found in the top 2 inches of his soil. Since he plants corn 2 inches deep, many nutrients were above his corn roots. In dry weather, he was seeing stunted corn and nutrient deficiencies (P deficient purple corn). For every $1 in fertilizer (P & K) applied every year, he got back about $.40 in additional corn yield. He had been applying commercial fertilizer for 30 years to his no-till fields by surface applying nutrients. When he started checking with soil test every year, he found that he was gaining abou

Roundup: Friend or Foe

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  Roundup or glyphosate (RR) is the most common agricultural herbicide used to kill broadleaf and grass weeds. In the USA, 280 million pounds of RR annually is used on about 298 million cropland acres. Worldwide, about 19 billion pounds RR (almost 10 million tons) have been applied since 1974. Roundup (RR) is a common generic name for glyphosate but it also called Rodeo, KleenUp, Accord, Imitator, Eraser, Pronto, Touchdown, Cornerstone, Buccaneer etc. The USA is the biggest user of RR in the world. Since many crops have been genetically modified to tolerate RR, it is commonly used on corn, soybeans, canola, sugar beets, cotton, and alfalfa. But it is also used as a weed burndown or to terminate cover crops before crops are planted or emerge including wheat, oats, sunflowers etc. Glyphosate (RR) is used almost everywhere because it kills most weeds effectively and cheaply. Over time, many weeds have become weeds resistant to RR because of over usage. Weeds are very resilient and often m

Beneficial Bacteria Biologicals

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  Biologicals are simply live microbes that perform many important soil and plant functions. Some microbes are biofertilizers (microbes that improve plant nutrition); biopesticides (microbes that control or kill pathogens, insects, other pests); others produce plant growth hormones or help plants survive environmental stresses (drought, temperature, soil pH, wet soils) etc. Biologicals are starting to become more common as farmers learn how to take advantage of the benefits they supply, especially in healthy soils and plants. Farmers have inoculated legumes and clovers with bacteria to fix nitrogen (N) in nodules. Now farmers can inoculate plants for bacteria that are free living and also supply N to all plants. There are at least 200 strains of bacteria that are known to live inside plants and around plant roots. With the new discovery of rhizophagy (plant roots eating bacteria for nutrients and growth), applying biologicals may soon be a common practice. Corn (C), Soybeans (S) and Wh

Roots eat Bacteria

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  Do plant roots really eat bacteria? The answer is Yes (sort of!). In the last 5-10 years, our understanding of how plants acquire nutrients has changed dramatically. With new stronger microscopes; Australian scientist and Dr. James White, Rutgers university have discovered that plant roots are taking in endophytic (translation: “within the plant”) bacteria and acquiring nutrients from these microbes. One study estimates that 47% of the atmospheric nitrogen (N) and perhaps as much as 70% of the plants N might be acquired from bacteria absorbed and living between plant cells and within plant cells. This newly discovered processed is called rhizophagy. We should not be too surprised. Farmers inoculate legumes (soybeans, peas) with Rhizobium bacteria which reside in plant nodules and fix N . Arbuscular Mycorrhizal Fungi (AMF) also enter roots and live between plant cells. AMF are like root extenders, bringing back water and soil nutrients in exchange for plant sugar. Endophytic bacteria

Drought Pre-Planning

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  Farmer’s fear drought which leads to reduced crop yields and profits. Worldwide, drought is affecting a number of countries: China, Argentina, European countries, and the USA. California, Arizona, Texas, Kansas, and Oklahoma have experienced severe drought soil conditions this year. The Midwest is dry and experiencing drought problems, especially the Mississippi river with reduced barge traffic. Most farmer’s want to know what is the probability of a drought next year? Currently, a strong La Nina for the past 3 years is transitioning to a El Nino, perhaps by late Summer 2023. In most cases, strong El Nino’s signal an increased probability of a drought in the Midwest. Coupled with La Nina and El Nino ocean currents, there are increased solar flares and sun spot activity expected to peak by 2025. While droughts are hard to predict, the probability of dry soil conditions or a drought in the next couple of years. If you knew a drought was coming, how would you change your farming practic

Vomitoxin in Corn

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  As harvest progresses, farmers are finding vomitoxin in their corn. Gibberella (GIB) ear rot is caused by Fusarium graminearum, a fungus that is also called Gibberella zeae. This pathogen infects corn and wheat causing ear rot, stalk rot, and head scab. Corn symptoms include a reddish or pinkish-white mold on the ear tips. This pathogen infects the pollen tubes at pollination and then produces vomitoxin and other toxins as it grows. The pathogen over-winters on plant residue, usually corn stalks/leaves and wheat residue (straw and chaff). GIB ear rot is most prevalent when cool wet weather occurs for about 21 days after silking. Fields most susceptible are corn after corn or corn after wheat, especially if the wheat was infected with Fusarium head scab. Corn that is stressed from lack of nutrients, by insects, or other types of plant stress (soil compaction, poor soil health) tend to have higher levels of GIB ear rot. Nutrient stress may come from nitrogen (N), phosphorus (P), and po

How No-Till Improves Land Values

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  No-till Farmer (farming magazine) recently put together a report: How No-till Improves Land Values. This report put an economic value on conservation farming practices that improve the environment, but also preserves our soil. While farmers own the land and have the right to farm it how they choose; long-term, society has an interest in preserving the land for future generations. Here are some results of research on the benefits of no-till to society. An organization called Rural Investment for Protecting our Environment (RIPE) came up with $112 per acre as the value associated with no-till farming. This included $7 for increased carbon sequestration, $16 for improved air quality and human health, $25 for better water quality, and $44 for improved soil nutrient management; all on a per acre basis. No-till Farmer has been documenting farmer benefits for 25 years with farmers indicated they saved $25-$90 per acre in reduced production costs. A conservative figure is $30/A on average fo

Tips for Applying Fall Lime

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  After crops are harvested, fall is a good time to apply lime. While lime can be applied any time, ideally, the soil should be dry to allow good spreading with out rutting up a field. Here are some tips for fall lime spreading. First, get a good soil test to evaluate soil pH. Dr. Steve Culman, Ohio State University says the ideal pH is dependent upon the crop and the subsoil pH. In western Ohio with calcareous soils (subsoils with limestone), lime is usually not needed until the subsoil pH for mineral soils gets below 6.0 for corn and soybeans and 6.2 for alfalfa. In other parts of the state (eastern and southern Ohio), where the subsoil pH is less than 6.0 for mineral soils, additional lime is recommended after the soil pH drops to 6.2 for corn and soybean, and 6.5 for alfalfa. Western Ohio soils needs less lime to buffer soil pH. Second, lime regularly. Soils that are regularly limed are not as critical as soils that seldom get limed and the pH gets too low. Regular liming maintenan

Tips for Late Wheat Planting

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  The wet spring weather this year has delayed soybean harvest and stalled wheat and cover crop planting. While late planted wheat may not compete with seedings made in September, late planted October and even early November wheat can often be successful. Every day that wheat planting is delayed past the ideal planting window of late September and early October, fall tillering decreases and yield slips. The situation is especially concerning in the Midwest, which has seen less wheat planted early this year due to late spring crop plantings and later crop harvest. University research from Michigan, Ohio and Pennsylvania relate how best to manage late-seeded wheat fields to minimize yield loss and other problems. Here are some of their recommendations. First, watch your crop rotation. Avoid planting wheat into a corn crop because as grasses, both wheat and corn share many similar diseases. Diseases like Take All, a fusarium species, and head scab - fusarium, cause large yield losses, per

Fall Nutrient Management

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  Crops flourish and grow quickly in the spring. The first cutting of hay may be 50% higher than any other cutting. It’s not just due to more water. Increased spring growth comes from plant available nutrients (PAvN) from dormant microbes. Usually, this spring flush lasts 30-45 days, but with good management, this growth (and yield) flush may last all summer. However, it starts with fall nutrient management. All soil nutrients are part of a biological system. Each element is like a component or part in an engine. If one component is lacking or missing, the engine may not run as well or even stop running. Soil nutrients, especially micronutrients, are the activators to many biological processes. Over the winter; microbes release nutrients when they die, are consumed by others, but also when they are active. Plant available nutrients (PAvN) include many elements. The major positive charged elements called cations include ammonium (nitrogen), potassium, calcium, magnesium, and even sodium

Striving for High Crop Yields

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  Everyone likes to follow a winner! Top farmers develop a suite of management practices that allows them to achieve higher average yields than their neighbors. High crop yields usually come from doing several things right and usually the weather has to cooperate. The world record holder on corn, David Hula, recently shared several of his high yielding management practices. Hula holds the all-time world corn yield record of 616 bushels set in 2019, on an irrigated strip till farm in Charles City, Virginia. Strip-till is a system where a 6-inch ban is tilled (fall or spring) before corn is planted. About 80% (24 inches in a 30-inch row) is left as no-till. The six-inch ban warms up quickly in the spring and allows corn to get a quick start. Cover crops can be planted between the tilled strips to add carbon and to improve soil health. Hula says getting corn off to a good start is a major key to high corn yields. The strip till section is usually a little drier and in a wet spring, much w

Beneficial Soil Fungus Part 2

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  Beneficial soil fungus called mycorrhizae fungi (MF) can optimize crop yields. MF use to be abundant be MF must have a live root as a host. Plowing soil, fallow periods, and annual crops caused many beneficial MF to died off. Long fallow periods, 14-16 weeks; greatly reduce (85- 98%) MF population levels while shorter fallow periods, 3-6 weeks; reduce MF populations 30- 70%. Some hardy MF species survive in tilled crop land but using cover crops with a live root, can gradually increase MF populations over time (maybe 5-10 years). Inoculating a crop with MF spores speeds up the process and crops respond quickly.  A full rate of MF inoculant, depending on formulation, costs about $12-15/acre. This rate is designed to provide 150,000 propagules (spores and root fragments containing MF) or more per acre. MF research on crops is extensive with over 155,000 published research articles at this time with 10X more research articles on the use of corn (maize MF) than corn using anhydrous ammon

Beneficial Soil Fungi

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  Mycorrhizal fungi (MF) are one of the most beneficial organisms on the planet. These fungi colonize plant roots, acting as root extenders to aid roots. MF are more efficient than roots and MF benefits are numerous. Increased root mass. Plants allocate a certain amount of energy to the root system. In the absence of MF, plants must build root hairs, which requires a lot of energy. Plants colonized with MF do not produce root hairs and instead use a much smaller amount of energy to allow MF to perform the job of absorbing water and nutrients. The hyphae (root-like structure) of MF is about 1/16th the diameter of a root hair (1/10 the diameter of human hair), and it takes about 1/256th the energy investment per mm of length to build than a root hair. With this energy savings, MF colonized plants tend to build much better root systems. Improved drought tolerance. One of the primary functions of a root system is water uptake and a colonized root will do so much better than an uncolonized

New Soil Health Measurements

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  The Soil Health Institute (SHI), a non-profit organization dedicated to enhancing soil productivity, recently announced results from a 3-year research project on identifying soil health measurements across North America. Over 100 scientist reviewed data from 124 sites in Canada, Mexico, and the United States; comparing conventional tilled farming systems to longterm no-till, cover crops, and perennial cropping systems. Over 30 key soil health measurements were taken at various research sites in this project. Measurements were taken across a wide range of climates, soil types, environmental conditions, cropping practices, and different management. Scientifically, evaluating that many sites and that much data gave the project the scientific rigor to valid these soil health measurements across many different systems. Evaluating soil health is all about how well soil’s function. Functions such as water, carbon, and nutrient recycling are important for good plant productivity. Healthy soi