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Calcium Product 98G


Natural vs. Synthetic Gypsum

Synthetic Gypsum

What is Gypsum?
Gypsum is a mineral that has been used in agriculture for a long time. Its chemical name is calcium sulfate dihydrate (CaSO4 • 2H2O). It provides a sulfur source in the plant available form, sulfate, and provides calcium – both essential nutrients in crop production.

SO4 is naturally mined gypsum
SO4 is pelletized from gypsum that is naturally mined in northwest Iowa. Gypsum deposits were left behind when inland seas that used to cover Iowa dried up and receded.

Synthetic gypsum is a byproduct of burning coal
In contrast, synthetic gypsum (photo above) is a byproduct of burning coal. This source is commonly referred to as synthetic or flue gas desulfurized (FGD) gypsum. Power plants have ‘scrubbers’ that control emissions from their flue stacks. The process in its entirety is called flue gas desulfurization.

In short, these scrubbers filter by forcing sulfur dioxide and calcium carbonate (limestone) to react with one another, which creates calcium sulfite (CaSO3). Most power plants also use an additional step called ‘forced oxidation,’ whereby the calcium sulfite is oxidized to calcium sulfate, or synthetic gypsum. The resulting moist material is either landfilled or used in various industries around the U.S. – wallboard for instance. 

Challenges with synthetic gypsum
There are a few challenges with synthetic gypsum worth considering:
1. Coal contains heavy metals, which are generally isolated in the scrubbing process but occasionally can end up in the synthetic gypsum, raising obvious concerns about agricultural applications.
2. In bulk form, the material contains high moisture levels, making it difficult to spread and manage. As a result, recommended application rates are in the 1,000+ lbs/A range, which can create imbalance in the soil. These rates lack scientific evidence supporting their use in Midwest agriculture.
3. The purity of synthetic gypsum is only as good as the starting feedstock (limestone) and the system that produces it, creating highly variable chemical characteristics. Because of its synthetic/by-product nature, it will never be registered for organic use.

Synthetic gypsum is difficult and expensive to pelletize due to its fine particle size and requires the use of specialized binders and additives. This results in slow breakdown and activity in the field.

In summary, natural gypsum is mined from the earth while synthetic gypsum is a byproduct of burning coal. SO4 is pelletized, natural gypsum. It’s consistent pellet size allows it to blended and applied with other dry fertilizers.


Pure Products and Powerful Results. Since 1987

Calcium Golf TURF Bunker Sand Calcium Golf TURF Bunker Sand

Since 1987, Calcium Products, Inc. has been using pure-mined minerals to help growers achieve highly effective, natural soil enhancement. Calcium Products’ source mine, in operation since 1880, is in the heart of one of the world's purest limestone and gypsum deposits. We currently make over 100 products and employ close to 70 people, operating plants 24 hours a day/6 days a week. Our products have been sold in every state in the nation and in several foreign countries.


Blending SO4 with fertilizers

We got a question today on Twitter about blending calcium sulfate with other fertilizers so we're sharing the answer with everyone....

Our SuperCal SO4 gypsum (calcium sulfate) is compatible with any standard fertilizer. You should blend it to meet our application rate on the bag. Target your application at roughly 10-20 lbs of our product per 1000 square feet. 

Our calcium sulfate is analyzed at (0-0-0-21Ca, 17S), so for each 100 lbs of product, there is 21 lbs calcium and 17 lbs sulfate. That means in 10 lbs of product, there would be 2.1 lbs calcium and 1.7 lbs sulfate applied over the 1000 square feet.

Example, if you have a fertilizer that is 10-10-10 and you are targeting 1 lb of N per 1000 square feet, you need 10 lbs of that fertilizer to accomplish that. If you want to blend in our product to supply Ca and S for that same area, you should blend 10-20 lbs of our product in with the 10 lbs of standard fertilizer. If you want to make it simple and blend a whole 50 lb bag with our product, you can assume, at that targeted rate, you'll cover 5000 square feet with a 50 lb bag of 10-10-10, so you'll want to add 50-100 lbs of our product with that fertilizer.


More questions? Email me!


Agri-Trend 2012: Farm Forum Event

Our own Craig Dick is headed north to the Agri-Trend 2012: Farm Forum Event in Saskatoon, Saskatchewan, Canada. It's a conference and trade show and we're thrilled to be there with our distributor, ENR Distribution.

Craig will actually be speaking on Wednesday afternoon. He is going to cover the agronomic role soil pH, calcium and sulfur play in soil fertility and high yielding crops. If you're at the event, come learn why you can't afford to ignore these critical yield increasing items.

If Craig gets a chance to attend other sessions, he'll be tweeting about them with the hashtag #FFE12. Follow us on Twitter to read the insight he shares.


Wet soils require extra nutrients for high yields

How will all the excess moisture from this growing season affect your fertility plans?
Did you know that wet soils can cause deficnecies in nutrients other than Nitogens?
Here is some excerpts from an article written by Neil Kinsey 
...excess moisture has caused some fertilizer nutrients needed for good crop production to be leached out, washed downward out of the topsoil. This is especially true for nitrogen, sulfur and
boron, which is generally expected to be the case with highly active soil water systems. But often overlooked is the loss of calcium, which is another element that can be lost from higher rates of moisture.
But just applying some type of lime to correct the pH is not the best answer. In fact, some of the fields that have received high magnesium (dolomite) lime can still have an adequate pH and yet be limiting your crop yields.
When dolomite is applied in too large a quantity, it can cause an excess of magnesium and have a negative effect on yields. In corn, on medium to heavy soils, a high level of magnesium (above 15 percent) costs the farmer 10 bushels of corn per acre. Above 20 percent magnesium on the soil test reduces the yield by another 5 or more bushels per acre. In addition, it will require more nitrogen to produce each bushel of corn every year until the problem is corrected. In legumes, taking soybeans as an example, 13 to 14 percent magnesium levels can cause losses of 10 bushels per acre per year, even when all other nutrients are present in the proper amounts.
For more information on wet soils
Yield Starts Here is a blog for farmers, focusing on increasing yield and profitability by focusing on the soil. It is managed by Craig Dick, a Blogronomist and Sales and Marketing Manager at Calcium Products. Find other articles by Craig and guest writers at .

Calcium Impacts California Soils

 Patrick McGinnity sent me a great article today on calcium.

It is from The most widely read agricultural publication in California, Ag Alert® is published weekly by the California Farm Bureau Federation and distributed as a membership benefit to Farm Bureau members. We publish online the top stories from each edition.

To read the article, click on the following link

To subscribe to ag alert, go to

Yield Starts Here is a blog for farmers, focusing on increasing yield and profitability by focusing on the soil. It is managed by Craig Dick, a Blogronomist and Sales and Marketing Manager at Calcium Products. Find other articles by Craig and guest writers at .


Low Boron and Excess Iron, is there an interaction?



One of our customers emailed in with some questions. They wanted to know about lower pH levels and higher iron levels & potential correlations and were seeing seeing sub Boron and excess irons in tissue samples.

After some research, near as I can tell boron and iron have no interactions. Both are however affected by calcium (See chart 1).

More calcium will reduce iron uptake. Boron and silicon help to increase calcium uptake.

In low pH excess phosphorus can reduce boron uptake

High potassium can reduce boron uptake

Boron deficiency

  • Reduces growth of soil bacteria.
  • Poor movement of sugar and carbohydrates in the plant.
  • Affects timing of maturity, pollination, and reproduction.

Some old articles on boron and silicon:


What about Iron?

Injury due to high soil iron concentrations is not common under neutral or high pH soil conditions. Toxic situations occur primarily on acid soils (< pH 5.0) and where excess soluble iron salts have been applied as foliar sprays or soil amendments (poor quality limestone).

The first symptoms of iron toxicity are necrotic spots on the leaves. An unusual form of iron toxicity has been observed in Michigan on organic soils and high organic sands. Some iron-rich, low pH, low manganese soils create an environment in which an interaction between the iron and manganese in the soil reduces manganese uptake by plants. The symptoms observed on the plants are of manganese deficiency, but the low plant uptake of manganese is caused by excessive available iron in the soil.

Toxicity Symptoms

Iron toxicity is primarily pH related and occurs where the soil pH has dropped sufficiently to create an excess of available Iron. (I think this statement is wrong, not low pH, low calcium is the issue cmd)

As with some other nutrients, the visible symptoms of Fe toxicity are likely to be a deficiency of another nutrient. Fe toxicity can also occur when Zinc is deficient, or the soil is in a "reduced" condition caused by very wet or flooded conditions. Excess Fe can result in Dark green foliage, stunted growth of tops and roots, dark brown to purple leaves on some plants (e.g. bronzing disease of rice).

High levels of nitrogen and potassium increase iron uptake

Excessive iron can reduce uptake of manganese, additions of sulfur improve uptake of manganese

High iron can reduce zinc uptake, and low zinc uptake is often found with low manganese

Iron excess:

  • Interferes with phosphorus absorption.
  • Requires use of higher levels of potassium to regulate.
  • Can cause Zinc deficiency

To reduce problems with excess iron make sure you have adequate levels of calcium in your soils and the pH is at least 6.5. SupeCal SO4 gypsum and SuperCal 98G limestone are great ways to ensure pro


Losing the Glyphosate Resistant Pigweed Battle, We can help you get back in the fight!

There is an interesting article in the July issue of No-Till Farmer .


Glyphosate resistant pigweed Georgia

"No-Tiller Losing Pigweed Fight"

Dyersburg, TN, farmer Eddie Anderson a 15 year veteran of No-Till PLOWED under 1000 acres to combat glyphosate resistant pigweed. Also in the article "glyphosate resistance is the single largest threat to production agriculture."


I cannot imagine undoing 15 years of work due to a weed control issue.


We have a customer and crop advisor that is working in Georgia and has seen some tremendous results with SuperCal 98G as part of his comprehensive soil restoration and fertility improvement program.



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