Interpreting Wildlife Foot Plot Lab Results
Once you receive your test report, an important measurement to pay attention to is the pH. Soil pH affects the plant's ability to absorb nutrients and grow. A common problem with many soils is that they are too acidic (which means they have a low pH). In fact, it's quite common for soil test reports to come back recommending three tons of lime per acre! Too much lime is rarely a problem, so don't worry if you think you put out slightly more lime than the soil report recommends.
A soil pH of 7.0 is considered neutral and is ideal for growing many agricultural crops such as alfalfa, while a soil pH of 6.0 is considered adequate for growing most food plot crops. A soil with a pH of 5.0 is 10 times more acidic than a soil with a pH of 6.0, and many of the nutrients in the soil will not be available to the crops because they will be tied up in the soil solution. Raising the soil pH makes the soil less acidic, releasing more nutrients allowing them to be available to a growing crop.Other benefits include improved bacterial activity and nitrogen fixation by legumes along with improved physical condition of the soil. We accomplish this by adding lime and mixing it into the soil.
An illustration of a low pH soil environment would be if you were sitting at a table heaped with food, but were unable to eat because your jaw was wired shut. There is plenty of food in front of you, but you are unable to consume it. Now if someone would unwire your jaw part way you would be able to take in some of the food, and the more it was unwired the more food you could eat. In the same way adding lime to the soil raises the soil pH releasing more nutrients from the soil solution so the crop can eat and grow.
Spreading lime on the surface of your plots and tilling it in is the best way to correct a low pH field. Whether the lime is referred to as aglime, barn lime, high-calcium, pel-lime or something else, there is little difference in the ability of the liming material to correct the pH of the soil. What can make a difference is the particle size, which relates to how fast the material will be dissolved in the soil solution. A coarse lime (60-69) will take longer to have the same effect as a fine aglime (80-89). Pel-lime is a fine lime that has been pelleted and will perform equal to a fine aglime. As a rule the lime you apply will take 6-24 months to dissolve and have an effect on neutralizing soil acidity. A common misunderstanding when liming is that the lime spread on the surface will be carried down through the top 6-7 inches of topsoil with rain water. This is not the case. Lime in any form will move very little in the soil profile and must be tilled and mixed with the topsoil to have the desired effect. Does this mean that lime applied to the surface and not mixed in is wasted? No, it just means you won't see much neutralizing effect until the soil is tilled mixing the top layer with lime throughout the 6-7 inches of topsoil.
In acidic soils, the nitrogen and phosphorus will be bonded to the soil and will be unavailable for the plant. Even when fertilizer is applied, only a small amount can be used by the plant and the rest will remain locked in the soil particles. Lime raises the pH level unlocking soil nutrients and helping in the break down of organic matter for use by the plants.
Taking the time to properly test your soil can be the most important thing you do this spring. Understanding your soil pH and what your phosphorus and potassium fertility levels are can help you make a better decision of what to plant, which fertilizer blend to use, and whether or not you need to apply lime. The information obtained from a soil test provides a roadmap for achieving successful food plots. You put a lot of effort and expense into striving for the best food plots possible; don't overlook the first and most important step.
For more information, please contact our soil testing professionals in Bonduel, Wisconsin.