Why You Should Soil Test Your Pastures in Fall 2018

Most farm managers know the importance of regular soil testing and fertilizing: it ensures that the soil contains enough nutrients and the right conditions for pasture forages to grow well and provide as much feed as possible for our horses. Normally, it is recommended to test soil every 3 years, and the test results from Penn State’s Agricultural Analytical Services Lab provide fertilizer and lime recommendations for the next 3 years. The fertility recommendations, in pounds per acre of nitrogen, phosphate, and potash, are based on the existing nutrient levels in the soil (except nitrogen) and the expected crop uptake and removal each year. In other words, if the soil nutrient levels are already optimum for plant growth, you only apply as much fertilizer as the plants will use that year.

However, it has been an unusual summer throughout Pennsylvania. In general, hot, dry weather reduces pasture growth and causes cool-season perennial grasses to slow their growth or go dormant. This year, excessive and continuous rainfall allowed pasture grasses to continue growing throughout the summer and may have caused a greater than normal removal of soil nutrients by the plants. In addition, some nutrients may have been lost through leaching or soil erosion and run-off. This may result in inadequate soil nutrient levels for spring growth, even when following the soil test results. Therefore, to give your pastures the best possible growth next spring, take a soil test this fall to see if your fertility plan needs an update. Test kits are available at your local county office, and instructions for sampling are included in the kit and also at Don’t Guess… Soil Test. When completing the sample submission form, make sure to use the yellow Agronomic Crops sheet and not the green Turf sheet.