Salt Index


If salt index isn’t a good predictor of fertilizer injury to many crops  — what should be considered when selecting a fertilizer?

There has been a lot of discussion about the term “salt index” and what it means with regard to crop safety for fertilizers. When synthetic fertilizers were first becoming prominent in the marketplace one of the concerns was the crop safety that each product provided and how that related to where a product should or shouldn’t be placed. The term “salt index” was used to help describe the relative safety of fertilizer products – both liquid and dry.  Over the years, the term salt index has been used for a variety of things, some that make sense, and some that were, perhaps, not technically accurate.

In order to understand salt index it is important to understand what is meant by the term “salt.” A salt is any chemical compound that is composed of a positively charged ion and a negatively charged ion. When most of us hear the word salt we tend to think of sodium chloride, or table salt. Sodium chloride is a salt, but it is not a common component of fertilizers.

The question is often asked about how much salt fertilizers have. In strict chemical terms fertilizers ARE salts. One of the more recognizable fertilizer formulas is K-Cl, or potassium chloride. That compound is 0-0-60 potash. The potassium component is a positive ion and the chloride component is a negative ion. That fertilizer, along with all others, are salts.

Why was the concept of salt index developed?  The original intent was to develop a scale, or index, of the potential for a fertilizer to cause crop injury. The actual numbers reported can be measured values using electrical conductance tests, or can be calculated values based on product components. It is easy to see how different analysis methods can give different index values, so comparing the salt index of various products is problematic unless the products were all measured (not calculated) using the exact same methods.

Is the salt index number of any value when describing the potential for fertilizer injury?  Not as much as it used to. Some literature suggests that fertilizers with salt indexes above 20 should not be applied near the seed of sensitive crops. Commodity fertilizer products such as potash or DAP are well known to cause crop injury when placed too close to a sensitive seed. Some liquid fertilizers, such as 10-34-0 or 6-18-6, can be applied in-furrow to certain crops but with significant rate restrictions. Newer technology products – including many AgroLiquid products – are safe for in-furrow application to many crops, including some products that have salt index values higher than 20.

If salt index is not a good predictor of fertilizer injury to many crops what should be considered when selecting a fertilizer? First and foremost, crop safety and performance of AgroLiquid products should be the focus of any discussion. AgroLiquid product crop safety and performance claims are backed up by over 20 years of research and field experiences, and don’t need to be justified by a laboratory value.

When selecting fertilizer products and application placement it is important to use the best agronomic practices for the product, crop, and row spacing. Corn and soybeans, for example, have different limitations on what rates certain AgroLiquid products can be applied in-furrow or as a foliar spray. Some of the vegetable crops, on the other hand, should not have in-furrow applications of AgroLiquid products at planting.  In addition to the product itself there are several environmental conditions that need to be taken into account when determining crop safety risks. Soil environmental conditions play a large role in crop response to fertilizer products, with colder, dryer soil conditions having a higher potential for adverse crop response compared to a warmer, moist soil. Foliar applications have additional issues to consider with regard to crop safety and performance. Crop growth stage is a very important factor in the safety and performance of foliar fertilizer applications.  Tank mix partners and surfactants may also play a role in safety and performance. When tank mixing with crop protection products it is important to READ AND FOLLOW LABEL DIRECTIONS of the pesticides. Pay special attention to tank mix restrictions and compatibility testing instructions on the pesticide label.

Reminders about salt index

How it relates to AgroLiquid products:

Don’t worry about absolute numbers.  Methodology, test conditions, and the products tested all influence the index value that is reported. Also, don’t get caught up in salt index comparisons with other products.

Do consider the safety, flexibility and performance of AgroLiquid products, and the research plus field experiences that prove performance.

Do select and apply fertilizers based on sound agronomic practices. Consider what crops, application methods, tank mix partners, and environmental conditions are present when making fertilizer decisions.

Fertilizer Program Sustainability in Corn 2011-2015

Senior Research Manager, Dr. Jerry Wilhm discusses how and why the lower applied rates of AgroLiquid nutrients are sustainable and more efficient in feeding the plant the nutrients it needs to thrive. In this short video, Dr. Wilhm further demonstrates this through a four-year sustainability study from the North Central Research Station (NCRS).

Download a pdf version of Fertilizer Sustainability in Corn

Increasing Grape Yield: Switch to AgroLiquid

In grapes, a combination of variety, management, and training system dictates how much quality fruit the plant can produce. One of the best options is using fertilizer applied in the spring that can be easily taken up by the vine. Over the last four years, we have been looking at what AgroLiquid products can do on grapes. All fertilizer is soil applied in the spring underneath the vines.

  • Conventional Program: 12 gallons of 28%UAN + 12.9 gallons of 10-34-0 + 100 lbs. of sulfate of potash.
  • Agroliquid Program: 11 gallons of High NRG-N + 4.2 gallons of Pro-Germinator + 4.2 gallons of Sure-K + 1 gallon of Micro 500 + 0.125 gallons of Manganese.

Details about this project can be found in the 2015 Research Report.

2015 grape research

Research Field Days 2015

5 Popular Cover Crops

As interest in cover crops continues to grow many producers are looking for the best tried-and-true crops to blanket their fields this fall. While no cover crop is perfect for all situations a few stand out among the competition time and time again. In a web poll conducted by No-Till Farmer between mid-July and mid-August, 2014, respondents consistently reported plans to utilize five cover crops above all others.

Predictably, the popular Tillage Radish topped No-Tillers’ lists, with 62% of poll takers planning to plant radishes as part of their cover crop rotation in 2014. The practice of using radishes in a cover crop rotation has gained traction in recent years as more producers are turning to no and reduced tillage practices in an effort to reduce compaction and erosion while increasing soil organic matter. The tillage radish’s deep tap root has proven a valuable alternative tillage tool in and of itself, no doubt aiding in its skyrocketing popularity.

While Cereal Rye didn’t bring in quite as many votes as Tillage Radishes, more than half of respondents reported plans to plant the crop this year. Its ease of establishment and performance as both a nutrient scavenger and erosion controller are likely among the top reasons for its high ranking, though producers should be aware that cereal rye does not winter kill — a trait that can be either positive or negative depending on your circumstances.

Clover came in third in the poll, with 35% of respondents reporting plans to include the legume in their cover crops this fall. Compared to many other cover crops, clover’s low growth and nitrogen-fixing abilities can be a big advantage to producers looking for those traits along with their erosion control. Last, but not least, Annual Ryegrass and Oats came in a close fourth and fifth in the survey with 32% and 31% of respondents reporting plans to utilize them, respectively. While Annual ryegrass offers very high palatability for producers looking to turn stock out on their fields, oats are a top choice at the AgroLiquid North Central Research Station, where Senior Research Manager Jerry Wilhm reports they are easy to establish and offer the winter kill the busy research team prefers.

Cover crops can be a valuable tool in a well-rounded production toolbox. In combination with the 4-R’s of nutrient stewardship, cover crops can help producers better manage both the plant nutrition in their fields and their nutrient applications. Valuable as erosion control and helpers of both soil tilth and organic matter, cover crops can be both production and public relations-friendly — especially for farms near and inside sensitive watershed regions. For more information, reach out to an AgroLiquid Sales Account Manager near you.

LEED Gold Certified

LEED, or Leadership in Energy & Environmental Design, is the recognized standard for measuring building sustainability.  The LEED program provides third-party verification of green buildings. These buildings satisfy specific requirements put in place by the U.S. Green Building Council, and earn points to achieve different levels of certification.

The number of points a project earns is based on specific categories. The main point categories are sustainable sites, water efficiency, energy & atmosphere, materials & resources, and indoor environmental quality credits. Points are allocated based on the environmental impacts and human benefits of the building. Projects achieve certification based on the following point levels:

  • Certified: 40–49 points
  • Silver: 50–59 points
  • Gold: 60–79 points
  • Platinum: 80+ points

LEED certification is important to Agro-Culture Liquid Fertilizers because we care about the sustainability of our environment. AgroLiquid’s corporate headquarters is LEED Gold Certified. Our focus is on being environmentally responsible with our fertilizer and in everything we do.

For more information on LEED Cerification visit:
To learn more about AgroLiquid’s certification click here.


Young Farmers & Ranchers Meet Winners

On December 8, 2013 the Young Farmers and Ranchers Collegiate and Open Discussion Meet took place at the CFBF 95th Annual Meeting in Monterey CA. Agro-Culture Liquid Fertilizers Lonny Smith attended as a judge, along with his wife Kim. “I was privileged,” said Lonny Smith, “to judge the opening 2 rounds of the Collegiate Meet, the Semi-finals of the Open Meet, and the Collegiate final four.” The overall meet winner, Jake Carlson, was awarded $1250.  1st Runner up, Audra Roland, received $750, and both 2nd and 3rd runners up received $500. Jodi Raley, Jake Carlson, Audra Roland, and Rachel Wright of Fresno State were on the winning team receiving $250. Agro-Culture Liquid Fertilizers provided the award money for this event.

CAFBLonny Smith, AgroLiquid Senior Marketing Manager & YF&R Collegiate Discussion Meet Judge, w/ YF&R Collegiate Discussion Meet Participants.

CAFB1Left to Right: Audra Roland (1st runner up), Jake Carlson (YF&R Collegiate Discussion winner), Jodi Raley (3rd runner up) and Lonny Smith


(Webinar) Getting More For Less From The Fertilizer You Apply

No-tillers can’t afford to waste money on applied fertilizer. Neither can the agriculture industry continue to watch these resources negatively impact watersheds without expecting possible severe regulations. Nobody knows that any better than no-tiller Mike Starkey of Brownsburg, Ind., whose farm lies right at the base of the Eagle Creek Watershed that supplies the city of Indianapolis its drinking water.

This 1 hour webinar produced by No-Till Farmer Magazine originally broadcast November 27th, 2013.

AgroLiquid Recognizes Ovid Elsie FFA

As an FFA Foundation Member, Troy Bancroft speaks about his passion for supporting FFA and the future agriculture industry. Recently the Headquarters of AgroLiquid had a public open house and the Ovid Elsie FFA Chapter of Michigan helped assist at this large event. To show his gratitude Troy awards them for their help.

CA Part 8

Part 8:

To prepare for the layoffs many food lines have been set up and are prepared to stay running during the winter. The Endangered Species Act will cause collateral damage. For every $1 spent on the farmer approximately $7 is spent in town. These effects will hurt not only workers, but the government and schools as well.

Listen for the last section of the series.