News

Nutrient Removal in Grain

A good understanding of the amount of plant nutrients removed from the soil in the harvested portion of a crop is an important aspect of nutrient management. While a number of sources provide estimates of the amount of plant nutrients removed with a harvested crop, more precise nutrient removal values can be obtained by analyzing the concentration of nutrients in the crop. This can be done by submitting grain samples for a Crop Nutrient Removal Analysis.

There are several factors that can cause the actual concentration of nutrients in a given crop to vary from the average, including weather conditions, plant genetics, management practices, and soil properties

Nutrient removal analysis is similar to other plant tissue analyses in which the material is dried, ground and digested so that the concentration of various nutrients such as nitrogen, phosphorus, potassium, sulfur, calcium, magnesium, and various micronutrients can be determined for the sample. For grain samples, the results are then calculated and expressed as pounds per bushel based on a standard test weight and moisture content for a given crop. As with any other analysis, proper sample collection is crucial. For grain crops, collect a sample of grain that best represents the entire area, and submit 1 to 2 cups to the lab for analysis. Results will be presented on a pound per bushel and pounds per acre basis. The crop removal data can be reported based on the actual crop yield for the sampled area if the yield is provided for the submitted sample.

The utility of this type of analysis is not limited to grain samples. This data can be very useful for determining nutrient removal for other commodities such as fruits, vegetables, hay, straw, and silage. Since harvesting these crops often removes greater amounts of vegetative material and the concentration of nutrients in vegetative parts of a plant can be quite variable, nutrient removal values can differ considerably. To analyze for nutrient removal in these crops, submit 1 to 2 pounds of material for analysis.

Although considerable differences may exist between the results of a specific analysis and the reference values, this data is not intended to assess the fertility status of a crop or diagnose nutrient deficiencies. While nutrient removal data can be a valuable tool for managing soil fertility, it is only one piece of the puzzle. A good routine soil sampling plan remains the basis for a sound soil fertility program.

Data Security

Laboratory data is an important and valuable asset. As an independent laboratory, it is important for us to assure our clients that their data remains their property, and that safeguards are in place to prevent information from being released to individuals not entitled to it.

We are occasionally requested by a client to send copies of reports or data files to someone else. We are very happy to do this, but are aware of the importance of this data. Our primary responsibility regarding the confidentiality of our reports is to our client that is invoiced for the services provided. That report may represent samples that were taken for a customer of our client, but the data is still the property of our client, not their customer.

In order to release data to another party, we require approval from an authorized representative of our client. The preferred method is by email or letter, but can be given via phone call if that is the most convenient. We recognize that this might be extra work for you, but we want to ensure that your information is protected.

If data is to be routinely copied to another party, information regarding this can be set up in our client database. If changes in client personnel or addresses occur, we need to be notified so that data is not sent to an incorrect address. Please contact the lab regarding your account if you need to verify or change who is authorized to receive your data.

The Basics of Lime Testing

The majority of our soils in the Great Lakes region require regular liming in order to maintain pH levels that are within the appropriate range to maximize crop growth and productivity. The quality and effectiveness of a liming material can vary tremendously depending on the source, composition, and physical properties of the material, so having a reliable lime analysis is critical to ensure that the proper type and quantity of liming material is used to get the desired effect.

Agricultural lime quality is usually measured by three characteristics:
 

1. Purity - commonly expressed as calcium carbonate equivalent (CCE)

2. Particle size – finer particles react more quickly to raise soil pH

3. Moisture – increases weight of the material without increasing effectiveness, essentially “diluting” the material

 
A number of materials can be used to increase the pH of the soil, but historically the most common material is ground limestone, commonly referred to as ag lime. Ag lime is finely ground rock containing high levels of calcium carbonate (CaCO₃) and magnesium carbonate (MgCO₃). It is actually the carbonate (CO₃^-) in lime that reacts with acidity (hydrogen) to increase soil pH.

Calcium and magnesium in lime, in addition to being essential plant nutrients, exchange with hydrogen (H⁺) held on cation exchange sites, moving H⁺ into soil solution where it can be neutralized by carbonate.

Particle size determines how quickly lime will dissolve and react in the soil. Generally, 40-50% of the particles in a good quality liming material will pass through a 60-mesh sieve. States in this region have different lime quality systems, with state-specific terminology and measurements.

A&L Great Lakes offers a Fact Sheet, entitled Adjusting Lime Rates, which provides details on how to make adjustments. A & L Great Lakes has also developed a spreadsheet which outlines various states’ systems and helps adjust rates for a particular liming material. These useful tools are available from our website at www.algreatlakes.com.
 

Feeding Drought Stressed Corn to Livestock

The rainfall this summer has been highly variable throughout the region, and some areas have been exceedingly dry, particularly during July. During times of extended drought when corn grain yield potential is severely limited or nonexistent, the plants may still offer a valuable source of nutrients for livestock provided careful attention is given to how it is harvested and fed. Due to the danger of nitrate levels being elevated during periods of drought, the safest option to use the crop as feed is to ensile it.  One-fifth to two-thirds of the nitrate in the plant may be dissipated during the fermentation process, but remember that this process takes up to 21 days to occur.  Nitrate concentration is highest in the lower one-third of the corn stalk.  If the crop is to be cut for use as feed, leave the bottom third of the plants in the field.

If moisture conditions improve and the corn begins to green up and resume growth, nitrate conversion to proteins accelerates rapidly and ultimately will return to normal. DO NOT harvest or graze corn plants for 5 to 7 days after a heavy rain has stimulated renewed growth! When the plant begins to grow again, nitrate levels will increase for a few days, creating very high concentrations in the plant.

If you want to test the crop for the potential of high nitrate, obtain a representative sample of the field by cutting 15 to 20 plants at the height they will be harvested and cut those plants up to resemble a silage sample.  Ship the sample in a paper bag In order to reduce the risk of the sample rotting on the way to the laboratory.  The following interpretive guidelines can be used to assess the test results. More information about nitrate testing for feed can be found in our FactSheet, Nitrate Toxicity in Feed, available on our website.

Calendar Photo Contest Deadline Extended!

We have extended the deadline to submit photos for the 2019 A&L Great Lakes Labs calendar until August 31. There is still time to get us those great photos!

We want to see pictures that illustrate what fuels your passion for agriculture and customer service. When you get that picture captured, send it to news@algreatlakes.com along with your name and address. Please submit your pictures in the highest resolution possible before August 31^st, 2018. In September, we will select our favorite pictures, then we will be letting our followers on Facebook vote on their favorite, to be on the cover of the 2019 calendar. Follow us on Facebook for voting details.

Photo criteria 

• Landscape oriented photos preferred, but not required.
• Please share the highest possible resolution photo.
• Please try to avoid company logos and easily identifiable faces.
• No dangerous or illegal activities.

Rules

• Photo submission deadline is August 31^st, 2018
• One entry per person, you may submit more than one photo.
• Must be 18 years or older to enter.
• Need not be present to win.
• No purchase necessary.
• Submitting a photo gives A&L Great Lakes permission to use the photo for promotional use.
• Employees of A&L Great Lakes Laboratories, Inc. and their immediate families are not eligible for prizes, but may submit photos for consideration in the calendar.
• Use of images in promotional items does not increase your odds of winning a prize.
• Contest decisions and/or judgements by A&L Great Lakes Laboratories, Inc. are final.

Understanding Soil Test Phosphorus

Phosphorus (P) is a key nutrient for crop production, and keeping adequate levels of P in the soil is important for maximizing plant growth and development. However, understanding the various analytical methods for determining soil phosphorus can be challenging. The greatest confusion often lies in understanding why there are different analytical methods for determining soil P. The key to understanding this is to differentiate between total, available, and extractable levels of a soil nutrient.

Total P is the total amount of phosphorus in the soil. This can be P contained in organic materials, P in soil solution, exchangeable P, and P contained in insoluble mineral forms, and can be quite high in many soils. This information generally has limited agronomic use, however, because the amount of P that is actually plant available is generally only a small amount of the total P in the soil.
 
Of much greater benefit from an agricultural perspective is what is referred to as extractable P. Extractable P is the amount of phosphorus that can be extracted, or removed, from the soil by using one of a number of different types of chemical extractants. These extractants have been developed to remove certain forms of P from the soil, and this can be a more accurate index of what might be actually available to a growing crop The ultimate goal of an extractant is to reliably and consistently determine levels of the nutrient that correlate with the amount of that nutrient that might be available to a growing plant.
 
Bray-Kurtz P1 (Bray P1) has long been utilized in the Great Lakes region as the “standard” P extractant. It was developed in 1945 at the University of Illinois to correlate with the plant-available P fraction of the soil in slightly acid soils. Many of the P recommendation models, including the Tri State Fertilizer Recommendations for Corn, Soybeans, Wheat, and Alfalfa, still utilize Bray P1 soil test values in their equations due to the widespread use of the extractant when these models were developed.
 
Bray P2, or strong Bray, is a more acidic solution that extracts forms of P that are less soluble than those extracted by the Bray P1 method. This extractant was commonly used when rock phosphate was the major P fertilizer product used in agriculture. It is still utilized by many to measure less soluble forms of P, what is commonly referred to as “active reserve” P in the soil, although most P recommendation models do not consider Bray P2.
 
Olsen P, or bicarbonate P, is a procedure that was developed in the 1950’s for determining P levels in neutral to alkaline soils. These soils are more commonly found in areas west of the Great Lakes region, so this test is only performed by request.
 
Mehlich-3 is the most commonly used extractant currently employed by soil testing laboratories in the region. It is a relatively safe extractant to work with and can be used to determine levels of other nutrients in addition to P, which makes it a more efficient method than others. Mehlich-3 is effective on the same types of soils as the Bray P1, but Mehlich-3 soil test P values are somewhat higher than those obtained by a Bray P1 extraction. However, the Mehlich-3 values correlate well with Bray P1 values, so Mehlich-3 values can be regressed into a Bray P1 equivalent number by using a mathematical operation. This allows soil test P values to be reported as a Bray P1 equivalent, which is necessary for making P fertilizer recommendations.
 
For any type of laboratory analysis to be useful, interpretations must exist in order for the data to be utilized to make decisions on a field scale. While different extracts have been developed to target different forms of P in the soil that may be plant available, this does not mean that the values determined by an extraction are absolute quantities of that nutrient in the soil. Much research has been done to correlate these soil test levels with crop response to a fertilizer material, and it is that correlation that is necessary for interpreting this information and making decisions.

Time is Running Out!

It's almost the deadline to submit a picture for our 2019 A&L Great Lakes calendar! We want to see pictures that illustrate what fuels your passion for agriculture and customer service. When you get that picture captured, send it to news@algreatlakes.com along with your name and address. Please submit your pictures in the highest resolution possible before August 1^st, 2018. In August we will select our favorite pictures, then we will be letting our followers on Facebook vote on their favorite, to be on the cover of the 2019 calendar. Follow us on Facebook for voting details.

Photo criteria 

• Landscape oriented photos preferred, but not required.
• Please share the highest possible resolution photo.
• Please try to avoid company logos and easily identifiable faces.
• No dangerous or illegal activities.

Rules

• Photo submission deadline is August 1^st, 2018
• One entry per person, you may submit more than one photo.
• Must be 18 years or older to enter.
• Need not be present to win.
• No purchase necessary.
• Submitting a photo gives A&L Great Lakes permission to use the photo for promotional use.
• Employees of A&L Great Lakes Laboratories, Inc. and their immediate families are not eligible for prizes, but may submit photos for consideration in the calendar.
• Use of images in promotional items does not increase your odds of winning a prize.
• Contest decisions and/or judgements by A&L Great Lakes Laboratories, Inc. are final.

Precision Ag Adoption Rates Still Lag

The 2017 Purdue Precision Dealer Survey shares some interesting insight into the adoption of precision soil fertility management. Over 80% of ag dealers offer services like precision soil sampling and variable rate nutrient application. More recent practices such as satellite/aerial imagery are also gaining popularity, with about half of dealers providing these services.

The adoption of precision ag started in the mid 90’s, and it continues to grow, although not as rapidly as expected. Access to these services is not a limiting factor, but adoption still lags. As estimated by dealers in 2017, only 43% of producers are utilizing precision soil sampling, and only 38% are making variable rate applications. This means 5% of growers are spending money on the collection of spatially referenced soil samples and not gaining the benefit of variable rate application of fertilizer inputs.

Looking into the future of precision fertility management, there is tremendous potential and a significant amount of work to be done. These are just a few of the interesting facts contained within the Purdue survey data. To dig into the survey data for yourself, see the full report at http://agribusiness.purdue.edu/files/file/croplife-purdue-2017-precision-dealer-survey-report.pdf .

Soil Applied vs. Foliar Applied Nutrients

Both soil-applied and foliar-applied nutrients have a place in modern agricultural production systems.  Historically, the vast majority of nutrients were applied to the soil, either as manure or some other type of organic material, or as synthetic fertilizer materials. This method has a number of distinct advantages.

Perhaps the most significant advantage of soil-applied nutrients is that this method supplies nutrients where the plants are designed to take in nutrients: at the roots. The roots of higher plants are adapted to take in nutrients and water from the soil and distribute them throughout the plant through the plant’s conductive tissues. Conversely, plant leaves are more adapted to keeping materials out of the plant due to their structure and composition since few nutrients are taken into plants via the leaves in a natural system. Because of this, plant roots can assimilate more nutrients into the plant than can the leaves of a plant.

However, foliar-applied nutrients also have a number of distinct advantages over soil-applied nutrients. One of the most significant of these is the rapid intake of nutrients. Because these materials are applied directly to the plant rather than the soil, their intake is not dependent on the nutrient moving through the soil and into the root. Therefore, they can have an immediate impact on the plant, which is critical when a given nutrient is lacking. Most modern foliar fertilizers have been formulated to ensure quick penetration into the plant, which can speed this process even further.

Another major benefit of foliar-applied nutrients is the fact that these nutrients bypass the soil altogether. Soil fertility is more complicated than the simple presence or absence of an element in the soil. For that element to be assimilated by the plant, it must be in a form that the plant can take up. Often a potential plant nutrient may be present in the soil, but certain soil conditions, such as pH, may cause that nutrient to be held in a form that cannot be taken up by the plant. If more nutrient is applied to the soil, it still may not benefit the plant because the underlying reason for the deficiency still exists. In these situations, foliar applications of nutrients may be the most effective way of supplying the needed nutrient to the plant.

Modern agronomic production is very sophisticated and requires a number of different techniques to meet the nutrient needs of the crop. Therefore, the best approach is to fully assess the situation to determine the best application method. Both application methods have distinct benefits and should be a part of the plant nutrient toolbox.

Assessing Soil Quality

Soil quality, often referred to as soil health, is a topic that continues to receive much attention.  As producers continue to push for greater yields and improved economics in their crop production system, more emphasis is being placed on the soil environment and its ability to produce a healthy crop in a sustainable way.  However, evaluating soil quality is not always as simple as pulling a soil sample and sending it to the lab.

The USDA-NRCS defines soil quality as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans”.  As evidenced by this definition, there is no one set parameter by which one measures soil quality.  The term can be interpreted in a number of ways depending on the situation.  Different soils in different locations will have different forms of “quality”, so the producer must learn to understand the capabilities of their soil and temper their expectations according to that capability.

One of the most fundamental steps to take when evaluating and managing for soil quality is to understand the soil that you are working with. Some properties of the soil cannot be practically changed.  These properties, known as inherent soil properties, are a result of how the soil was formed.  One example of this is soil texture.  A sandy soil will, for all practical purposes, always be a sandy soil.  Short of incorporating a huge amount of silt or clay, there is nothing you can do to change this. Massive changes like this can also result in negative impacts on the soil. However, there are other soil properties that can be influenced somewhat by management.  These properties, known as dynamic soil properties, can be influenced by how the soil is managed.  For example, soil organic matter content is a dynamic soil property.  It can change, however slowly, by how you manage tillage and crop residues. Soil structure can also be improved through proper soil management, again these changes take years to have a significant positive impact.

 A number of different assessments should be made, including a thorough examination of the physical properties of the soil. While soil health testing methods are being developed, these are not standardized today and interpretation of results still require validation. In addition, a standard soil test is also an important way to evaluate the chemical properties of the soil to ensure that nutrient levels are appropriate for growth.