Ready or not, here comes Spring!

Renewed Optimism

As we roll along in ’21 we are seeing abundant opportunities ahead for many of us. An increase in commodities should allow for a successful year in grain production. To those that rely on retail, I hope our breweries and farmers markets will fill with customers that are eager to get out and socialize with like minded individuals. Let us make sure that we can yield bountiful harvests and brew phenomenal beer. We at Ward stand ready to help with decisions so that you can maximize this opportunity. As we return to the fields and rangelands, we hope you stay safe, and the promise of opportunity keep your spirits high.

--Nick Ward, President, Ward Laboratories, Inc.

Soil Sampling for Lawns and Gardens

For many, springtime means lawn and garden season. Before fertilizing your lawn or garden, consider sending a soil test to Ward Laboratories.

For homeowners using conventional management practices (for example, synthetic fertilizers), we recommend our Routine Soil Analysis. For producers using natural approaches (for example, manure) a Haney Soil Health test may be beneficial.

Be sure to write on your sample submittal sheet that you would like fertilizer recommendations for a lawn or garden. Recommendations are always complimentary.

Finally, take a look at this video that details how to sample without a soil probe.

Why Honest Practices are Important When Dealing with Aflatoxin Infested Products

The possibility of contamination by aflatoxins is a critical aspect of food safety for field crops. Aflatoxins are toxic byproducts of the mold species Aspergillus produced when introduced to favorable conditions for production. Production of aflatoxin is most often brought on by environmental conditions or stressors.

In animals, aflatoxin can lead to damage of kidneys and liver, reduced productivity, and impeded growth. Consumption of contaminated grains by livestock can also lead to a spread of the aflatoxin into the subsequent animal products intended for human consumption. In humans intoxication can cause fatal acute illness and can be linked with increasing various cancer and cell mutation risks.

To protect consumers many countries, such as the United States, have developed regulations based on risk assessments to limit aflatoxin exposure. The Sanitary and Phytosanitary Agreement (SPS Agreement) of the World Trade Organization is an agreement established to balance the right of governments to protect plant and animal health, and food safety while preventing sanitary measures be manipulated as trade barriers. The SPS Committee develops guidelines to assist governments when implementing standards that recognize the use of different methods of production and treatment by differing countries who could potentially exporting and importing to one another. However, having no universal limits and leaving regulations in the hands of individual federal agencies does leave quite a bit of room for discrepancies. This is largely due to different perceptions of tolerable health risks (commonly associated with the level of economic development and vulnerability of nation’s crops). For example, according to a trade and food safety case study by the USDA, of the 48 countries with limits for aflatoxins in food, standards ranged from 0 to 50 parts per billion.

Because of the various uncontrollable factors that influence aflatoxin production, issues with regulatory standards could continue or even deteriorate further. Furthermore, perceptions of acceptable health risks are not likely to adjust drastically anytime soon because they rely by and large on the economic development of an area and on that area’s crop susceptibility.

Probably the best approach to lowering health risks and economic costs is to increase awareness and be cognizant of what risks can be associated with aflatoxin, along with encouragement to adopting process-based guidelines and practices. Increasing mindfulness of practices and actions which could be taken to minimize aflatoxin contamination among food producers and handlers would be a best defense against aflatoxin contaminated crops and their distribution.

In order to know the aflatoxin levels of feedstuff some version of an aflatoxin test must be performed. A decision on aflatoxin levels cannot be made by simply looking at the crop or feed, or by preforming any other type of mold test. A laboratory analysis is your best bet for understanding the level of toxicity in your crop or feedstuff. This video outlines some considerations and helpful tips for producers looking to test for aflatoxins. By testing for aflatoxins, producers can help to mitigate potential transportation or livestock and human health concerns derived from aflatoxins.

Water Holding Capacity

Soil health practices consider the physical and biological properties of soil, in addition to the traditional soil fertility or chemical properties of soil. Management of the physical properties of soil often translate to managing a plant’s access to water, either by increasing effective rooting area or increasing a soil water storage capacity. Available water holding capacity (AWC) is the quantity of total plant available water a soil can provide to a growing crop. This is a soil health test offered at Ward Laboratories. Determining AWC is a lengthy and involved process requiring specialized laboratory equipment and not something that can be carried out in the field.

There are soil characteristics like texture that influence AWC but cannot be controlled. However, there are other soil characteristics like organic matter and compaction that influence AWC and can be controlled. Managing for maximum AWC will buffer a crop from experiencing water stress in periods between precipitation and/or irrigation events. Management practices that increase AWC are those that increase soil organic matter, structure, and porosity. Tillage and traffic are management practices that negatively impact soil structure and porosity, and thus AWC. Compacted soils have reduced water storage capacity.

Farmers who adopt practices like no-tilling, planting cover crops, and controlling traffic can rehabilitate their compacted soil, although increasing AWC may be a long (5-10 year) process. By avoiding soil disturbance and through the influence of microbial activity, soil particles like sand, silt, and clay bind with each other and form into aggregates, which also increase AWC. Many of the practices that alleviate compacted soil will also build organic matter. Building organic matter should be a long-term goal and can be done by minimizing soil disturbance, growing perennial crops, growing high residue crops, and growing cover crops.

As previously mentioned, determining AWC is a time-consuming and labor-intensive laboratory process. Ward Laboratories usually takes 7-10 days to finalize the analysis once we receive the samples. The lengthy turnaround time is due to the time needed for water to reach an equilibrium within each soil sample. The sample is first split, then saturated with water and allowed to come to equilibrium. One part of the sample is placed inside a pressure chamber and pressure is applied at 0.1 bar. This is equivalent to the “permanent wilting point”. The rest of the sample is put in another pressure chamber and pressure is applied at 15 bar. This is equivalent to the “field capacity”. Once each of these comes to equilibrium again, roughly 7-10 days, the sample are weighed, oven dried, and weighed again to determine the amount of water present in each sample. The amount of water present in the “field capacity” sample minus the amount of water present in the “permanent wilting point” sample equals the quantity that would be available to a growing crop.

Contact Ward Laboratories for more information about running the AWC test or to find out if the AWC test is right for you.

Soil Test Methods

Ward Laboratories uses soil tests developed and calibrated by Land Grant Universities. Standard methods are published in several manuals. We prefer to use standard methods that have performed well for many years.

Soil pH & EC: We use a 1:1 water pH. This means we measure 10 grams of soil and 10 mL of water. The soil and water react for 30 minutes and then we read EC to measure soluble salts and measure soil pH to determine if soil is alkaline, neutral or acid. If sample shows acid pH (<6.5), a buffer solution is added to measure total acidity of the soil so we can predict the amount of lime to neutralize the acidity.

Soil Organic Matter: Soil samples, in crucibles, are dried for 2 hours at 105° C to drive off hydroscopic water. The samples are cooled to room temperature and weighed. Then the samples are heated to 360° C for 2 hours, cooled and weighed. The difference in the weights is calculated as percent organic matter by LOI (loss on ignition).

Nitrate: Nitrate is very soluble in soils, so it is easy to extract and measure the actual pounds of N per acre in the soil depth provided on the submittal sheet. We extract nitrate with KCl (potassium chloride) solution.   Flow injection analysis (FIA) analyzes nitrate.

Phosphorus: Our normal extractant for phosphorus (P) is Mehlich 3 solution. Phosphorus is attracted to soil particles and leaches very slowly. Research has found P moves about ¾ inch per year in loamy soil and up to 2 inches per year in sandy soils. Mehlich 3 extractant is similar to Bray P-1. Mehlich 3 is buffer with acetic acid, so the extract can measure available P in alkaline and calcareous soils. Other P tests we provide are Bray P-1, Bray P-2, and Olsen P (for calcareous soils).

Potassium and other cations: Our extractant for cations is ammonium acetate (pH 7.0). This extract floods the soil with ammonium that replaces potassium (K,) calcium (Ca), magnesium (Mg), and sodium (Na) on the cation exchange sites (CEC), as depicted in this video. Inductively Coupled Argon Plasma (ICAP) measures the cations in the extract. High temperature of the ICAP makes elements give off light. Each element has its own wavelength for detection. Sum of cations (estimated CEC) are calculated from the 4 cations and buffer pH. With sum of cations, we can report base saturation for each cation. Sodium base saturation is not a problem when less than 5% Na.

Sulfur: Mehlich 3 solution extracts soluble and available sulfur. ICAP analyzes sulfur. Sulfur in Mehlich 3 extract is mainly sulfate, which is soluble like nitrate.

Zinc, Iron, Manganese, and Copper: Our extractant is DTPA (pH 7.3). DTPA is a chelate that simulates uptake of the micronutrients by plants. Over a 2-hour shaking time, DTPA absorbs the micronutrients held on soil particles. This is a good estimate of their availability to plants. ICAP detects the 4 micronutrients.

Boron: A dilute calcium chloride hot water solution extracts boron. Boron is more soluble than phosphorus and less soluble than sulfate and nitrate. The hot water is a good measure of boron availability.   ICAP measures boron in the extract.

Chloride: Chloride is a soluble anion, like nitrate and sulfate.   Calcium nitrate solution extracts chloride that FIA measures. Chloride is in low supply in the Great Plains. Potash fertilizer is potassium chloride, so there is no shortage of chloride where potash is applied.

Join Us for "Bottom-Up Focus on Forage" Webinar Series!

We are excited to bring you our second webinar series, Bottom-Up Focus on Forage!

To view recordings of the first two webinars, click the titles below:

Alfalfa Breeding and Forage Quality Traits

Selecting the Right Seed or Forage Mix for Your Operation's Goals

To register for the remaining two webinars, click the titles below:

April 19: Producer Insights on Forage Production

May 17: Representative Forage Sampling & Utilizing NIRS Analysis of Forages