soil – Maryland Agronomy News

Soil Health Grant Available to Farmers

The Maryland Department of Agriculture (MDA) is accepting applications for the Farming for Healthy Soil Program. This three-year program begins this fall and provides financial assistance to farmers for implementing soil health practices on their farm. All livestock and crop (including grain, forage, fruit, and vegetables) farms are eligible for this program. Approved soil health practices include conservation tillage/residue management, multi-species cover crop mixtures, extended season cover crops, prescribed grazing, and precision nutrient management. Practices must be new to the farm; for example, adopting a practice never used on site before or changing from a one species cover crop to a two species cover crop.

Rates range from $10 to $55 per acre. Fields eligible for the Maryland Agricultural Water Quality Cost Share (MACS) Cover Crop Program can receive financial assistance from this grant in addition to the MACS funding; however, MACS enrolled fields must be extended season (planted before October 1 and terminated after May 1) or multi-species cover crops. The maximum funding per participating producer is $5,000 annually. Farmers must be in compliance with MDA programs (i.e. nutrient management) in order to participate.

Farmers are expected to commit up to three years of practice implementation on the same field(s). Soil samples will be taken this fall and again in the fall of 2022 to compare before and after practice implementation. Soil samples will also be taken in adjacent or nearby fields which have not had soil health practices to serve as control fields. University of Maryland Extension Agriculture Agents will be collecting the soil samples for farms in Western and Central Maryland.

The application form should be submitted to Kevin Antoszewski, MDA Healthy Soils Program Coordinator, at kevin.antoszewski@maryland.gov. For questions, contact Kevin (email is preferred, but a voicemail can be left at 410-841-5866) or Kelly Nichols, University of Maryland Extension Ag Agent, at 301-600-3577 or kellyn@umd.edu.

The Importance of pH and Liming Material

Kelly Nichols, Agriculture Agent Associate
University of Maryland Extension, Frederick County

“If I were stranded on a desert island and could do only one part of the soil test to determine how to grow food, I would test for pH.” This statement, made by Dr. Doug Beegle, my soil fertility professor, highlighted how important soil pH is. For most agronomic crops, the ideal pH is between 6.0 and 6.5. Alfalfa and barley prefer a bit higher pH of 6.5-7.0. Between the pH of 6 and 7, nutrient availability is at its optimum. Outside that range, key nutrients such as nitrogen, phosphorus, and potassium become more tightly bound to other nutrients and unavailable for the crops to take up (Figure 1). Below 6.0, nutrients such as iron, copper, and aluminum become more available, and in some cases could result in toxicity to the crop.

Over time, the pH of soil naturally decreases. So, to increase the pH, we add lime. The soil test results will provide the amount of lime needed to increase pH to the optimum level. The lab uses the current soil pH and acidity of the soil to determine how much lime is needed. (Your soil test may report the acidity, which is measured in milliequivalents per 100 grams [meg/100 g]). Also, if your soil test result includes the buffer pH, ignore that number. It is the pH of the buffering solution used during the test, and not the pH of the actual soil.

Let’s say your soil test result says that you need 2 tons of lime per acre to increase the pH to 7.0. Does that mean you can put on 2 tons of whatever liming material you like best? Not quite. The results are given based on the assumption of using calcium carbonate, which is considered pure limestone and given a rating of 100% calcium carbonate equivalent, or CCE. All other liming materials are compared to calcium carbonate and given their own CCE (Table 1). For example, burned lime has a CCE of 178. This means that it has more acid-neutralizing activity than pure calcium carbonate; therefore, less material can be used to obtain the same neutralizing activity as pure lime. Wood ashes, on the other hand, has a CCE of 40; therefore, more material needs to be applied in order to adjust the pH.

Don’t forget to take the price into consideration when comparing liming materials! For example, if ground shells are really cheap, that’s great; but it has a lower CCE, so you’ll need to apply more.

For more information, click here to read the Soil pH Management and Determining Lime Rates fact sheet.

Checking Soil Types At Home and In The Field

Jarrod O. Miller, Extension Agronomist
University of Delaware

While some precision agriculture software provides soil maps as a layer along with satellite imagery and yield maps, information on soil types is free and accessible to all growers. Soil surveys have be digitized and are available to anyone with an internet connection.

Web soil survey is one option to review soil types, but a more user-friendly website is UC Davis Soil Web (https://casoilresource.lawr.ucdavis.edu/gmap/). Sitting at a home computer, anyone can find fields by typing in an address to observe a satellite photo with soil boundaries. Standing in any field, a cellphone with good reception can zoom to the location you are standing. Soil maps are the easiest way to check under your feet without digging.

In Figure 1 we can observe a field south of the Harford County Extension office. Using the mouse or your cellphone touch screen, select the field/soil map unit will create a red (x) and bring up the soil series names (on the left of Figure 1). There may often be many choices for soil series, reflecting the variability in the field. Choosing the dominant soil name would be valid for general observations. South of the Harford Extension Office (Figure 1), the MsB2 map unit is dominated by the Montalto soil (85%).

By selecting the Montalto series (clicking the name in blue), a soil profile with horizon names and colors appears (Figure 2). Next to the soil profile are other options you can select, including particle size or organic matter content with depth. The organic matter content of the Montalto seires (Figure 2) is expected to be 2% at the surface, quickly dropping to less than 0.5% below 50 cm (20 inches). This doesn’t mean the entire field has this much organic matter, but it is good for comparing soils under production. These soil maps can be useful to those who want to explain differences in yield or growth across their farms, and can be used as an additional guide to soil sampling. If you would like help exploring these soil maps, contact your county extension office.

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