Weather for October has become more fall-like, though November is usually the cloudiest month of the year for our area. None of the ag weather people I get information from have suggested a winter forecast. Even with El Niño in the Pacific, they say it is too early to give a forecast for snow or cold with confidence. The Deerfield site records growing degree day (GDD) (heat units), and from March 1, 2023, through Oct. 10, the GDD was 2916, the lowest of the past six years. Rainfall since April 1 has been 18.46 inches, compared to the previous five-year average of 19.24 inches.
Officially, we have not had a killing frost at the Michigan State University Enviroweather station in Deerfield, which recorded a low temperature of 35.3 degrees on Oct. 8. The 30-year average fall frost date for Monroe County for a 32-degree frost is Oct. 18 and the 28-degree first freeze date is Nov. 5.
A frost is considered when we get a visible frost and is 32 degrees or higher while a hard freeze is 25 to 28 degrees and a killing freeze is 24 degrees and below. We can have a freeze without a frost, depending on the amount of water in the air. Air temperatures at the MSU Enviroweather station are measured at 5 feet above the ground and in the shade. Sensitive flowers or plants should be covered when the temperature is forecast around 28 degrees.
Soil testing is best done in the fall, when soils are normally drier than spring, but can be done at any time of the year. However, soil testing should be consistently done at the same time of the year. Without a current soil test, it is like driving without a map, whether electronic, like Google Maps or the old-fashioned paper maps. Farmers on a three-crop rotation should get a new soil test every three years; if on a two-crop rotation, every four years is recommended. Historically, the now-closed MSU Soil and Plant Nutrient Laboratory has shown Monroe County to have high soil phosphorus test levels and low soil potassium test levels. Nitrogen is such a mobile element that it is not measured in regular soil tests. Farmers can reduce phosphorus runoff into tributaries of Lake Erie by following the 4R nutrient management strategies of: the right source, the right rate, at the right time and in the right place. Attention to these factors will provide adequate nutrition for crop production while minimizing the risk of loss of nutrients to the environment.
Free analysis for nematodes should be considered if soybean yields were not as good as expected but no above ground symptoms were observed. Soybean cyst nematodes (SCN) are microscopic round worms that penetrate the cell walls of soybean roots and disrupt the flow of nutrients to the plant. As such they are a “hidden yield robber” that is the No. 1 pest of soybeans in Monroe County and the U.S. An estimated 70% or more of Monroe County soybean fields contain SCN from a survey done several years ago. The Michigan Soybean Committee is again providing soybean checkoff funding for the analysis costs of samples submitted to the MSU Plant and Pest Diagnostic Clinic. Interested persons can simply Google "MSU Plant Diagnostic Clinic" for sample information and forms. The clinic also works with plant health analyses, crop specific issues, weed and plant samples, nematode samples, insect and arthropod samples, and herbicide resistance.