The first dollar and best dollar spent on food plots is by conducting a soil test. The next best money spent is always on lime. Only after doing those 2 things should you then move on to what to plant and how to plant it.
What Causes Soil Acidity? Various environmental, climatic, and cultural factors can affect formation of acid soils. The most common factors are: -Parent material: Soils formed from acidic rocks have a lower pH than those formed from basic or alkaline parent material. -Leaching: Rainfall/irrigation leaches basic elements such as calcium, magnesium and sodium from the soil profile, leaving the acidic elements hydrogen, aluminum and manganese. -Cultural: Various management practices can affect the formation of acid soils, including: •?Soil erosion can cause the loss of basic elements thus increasing soil acidity. •?Removal of harvested crops depletes basic elements from the soil. •?Nitrogen fertilization can lead to the formation of acid soils when ammonium is converted to nitrate by soil microbes releasing hydrogen ions. Anhydrous ammonia, urea, and ammonium nitrate each produce about one-third as much acidity as ammonium sulfate.
Soil Acidity Measurement and Ratings The soil pH scale extends from 0 to 14 Soils with pH values above 7.4 are rated as alkaline neutral would be between 6.6 and 7.3 slightly acid between pH 6.5 - 6.1 moderately acid between 6.0 - 5.5 strongly acid between 5.5 - 5.1 very strongly acid between 5.0 - 4.5 extremely acid below pH 4.4.
Although a decrease in soil pH from 6.0 to 5.0 does not appear significant, there is a 10-fold increase in soil acidity for every whole unit change in soil pH.
Importance of Liming Acid Soils The most important benefit of liming acid soils is a reduction of the potentially toxic elements hydrogen, aluminum and manganese. Hydrogen ions only become toxic to plants in extremely acid soils (pH<4.0) and at very low calcium levels. As pH drops below 5.5, the concentration of soluble aluminum increases and becomes toxic to plant root growth when it exceeds 1.0 part per million (ppm). Below pH 5.2, the concentration of manganese can become toxic.
Optimum nutrient uptake by most crops occurs at a soil pH near 7.0. The availability of fertilizer nutrients such as nitrogen, phosphorus and potassium generally is reduced as soil pH decreases. Phosphorus is particularly sensitive to pH and can become a limiting nutrient in strongly acid soils. Thus, reduced fertilizer use efficiency and crop performance occurs when soil acidity is not controlled. Soil pH also affects the types, concentrations and activities of soil microorganisms. As pH drops below 5.5, the population of soil microbes changes and is reduced due to aluminum and manganese toxicity and lower nutrient availability.
Calculating Application Rates Based on Effective Calcium Carbonate Equivalence Effective Calcium Carbonate Equivalence (ECCE) combines the fineness efficiency rating (ER) and the calcium carbonate equivalence (CCE) to estimate the percentage of effective limestone in a given product. The percentage ECCE of a product should be available from the vendor. It is important because limestone rates recommended by soil testing laboratories are based on use of 100% effective limestone (dry weight basis). Agricultural grade limestones generally have an ECCE value of 50-70%. Therefore, if a soil test recommendation for lime is 1.0 ton/acre, the actual application rate of a limestone with an ECCE value of 60% would be 1.67 tons/acre. Limestones with an ECCE in the range of 95-100% are becoming increasingly available in the market. In many cases, limestone with an ECCE value of 95-100% that is priced slightly higher per ton is a better buy than standard agriculture grade limestone since a lower application rate is needed.
Helpful articles http://www.noble.org/ag/soils/limingquestions/ good basic question and answers
http://www.soils.wisc.edu/extension/wcmc/2011/pap/Wolkowski_lime.pdf this is an interesting study done by UW-Madison
http://extension.psu.edu/plants/nutrient-management/educational/soil-fertility/soil-acidity-and-aglime I like a lot of stuff coming from penn state
http://www.ncagr.gov/cyber/kidswrld/plant/nutrient.htm very basic, yet summary of plant nutrients
this comment should be significant and was in the above long posting.
Then there are many other factors that come into play with pH and liming. Soil organic matter, soil types, salt levels, and things that would make many people's heads spin. Using the k.i.s.s. method, liming is of the upmost importance as every seed planted has an effective pH range and they grow poorly outside that range.
Weed killers work poorly on low pH soils.
Weeds thrive on low pH soils.
Fertilizers are poorly utilized on low pH soils.
