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  New research from Virginia Tech University shows that small insects called springtails (Collembola species) help farmers fight herbicide resistant weed species in the soil. These tiny wingless insects are about the size of small rice kernel. They live in soil residue and feed on weed seed. There are more than 6,500 species of springtail (Collembola species) world-wide. Results vary by weed seed species depending upon the thickness of the seed coat.  Two Virginia Tech researchers (Jernigan & Sonoskie) found that in a 4-week greenhouse study, springtails reduced weed biomass by 23%. Unfortunately, at first the springtail affected weed seed seemed to increase weed germination for the first two weeks followed by a dramatic reduction in the last two weeks. The researchers think the springtails increased weed seed germination initially by breaking open the seed coat so that the weed seed could germinate faster. In the last two weeks, the germination was drastically reduced, pr...

Farmers first used cultivation to mechanically kill weeds. Hand hoeing, pulling weeds, then horse and tractor driven cultivators. Then they started using chemicals starting with 2-4D to chemically kill broad leaf weeds. New chemicals were developed and then came along glyphosate (Roundup) which became the most popular herbicide, especially when the glyphosate resistant gene was introduced into many crops. But like all new innovations, sooner or later they are replaced due to limitations.   Cultivation disturbed the soil and took a lot of fuel and time. Every time you disturb soil, you replant weed seed and you lose carbon in the form of soil organic matter. There can be as many as several hundred thousand weed seeds per square yard in soil. This weed seed can remain viable for a few years, a decade, or even longer. Weed seed with thicker coats and buried deep with tillage survive longer than those left on the soil surface with no-till. On the chemical herbicides, herbicide resistan...

  Soil testing methods are still about the same as they were 100 years ago and researchers and farmers are still struggling to interpret the numbers. However, a soil test is a good place to start to optimize crop yields. However, follow that up with scouting, tissue tests, and sap tests to verify and refine your analysis. Most standardized soil test report values for pH, phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). Soil test values are reported in Parts Per Million (PPM) or pounds per acre. The PPM times 2 equal pounds per acre. Actual soil nutrient levels generally are much higher; however, not all soil nutrients are available for plant uptake. Soil pH measures the acidity of a soil. A soil that is neutral has a pH of 7, while an acid soil has lower values and a basic soil has higher values. The pH values can range from 1 (highly acid) to 14 (highly basic), although most soil range from pH 5.0 to 8.0. To improve soil productivity and the release of nutrients, a...

  Fall and Spring are usually the time when farmers or fertilizer dealers take most soil tests to make recommendations for fertilizer applications. In the last several years, most dealers now do that service for their farmer clients. A few years ago, looking at soil test collected over several years, there was a big jump of .5 to 1.0% increase in soil organic matter (SOM) on all this no-till farmers fields. I started asking questions. He was already a no-tiller and using cover crops. Had he done anything different? No really. Then I asked who took the sample? He said the dealer. Who took them before? He said he had. Is there that much sampling difference between dealers and farmers? The biggest difference is that dealers use a machine (a soil sampler on a four-wheeler) while most farmers use a shovel or a probe. The standard procedure for collecting a soil sample 10 years ago was to wipe the soil surface clean of residue, then probe the soil, taking at least 10-15 samples in a rand...