ASSOCIATION OF AMERICAN PLANT FOOD CONTROL OFFICIALS (AAPFCO) OFFICIAL FERTILIZER DEFINITIONS
CALCIUM (Ca) PRODUCTS
Ca-1 — Agricultural Liming Materials
Moved. See T-129.
(SA 2020)
Ca-14 — Agricultural Slag
Is a fused silicate whose calcium and magnesium content is capable of neutralizing soil acidity and which is sufficiently fine to react readily in soil.
(Official 1958)
Ca-7 — Air-slaked Lime
Is a product composed of varying proportions of the oxide, hydroxide, and carbonate of calcium, or of calcium and magnesium, and derived from exposure of quicklime.
(Official 1950)
Ca-20 — Calcium Acetate, and its hydrated forms
Is the calcium salt of acetic acid. Anhydrous calcium acetate has the formula Ca(C₂H₃O₂)₂.
(Official 2001)
Ca-17 — Calcined Brucite
Moved. See Mg-1.
Ca-27 — Calcium Amino Acid Complex
Is a complex of calcium (II) with an amino acid product and is commonly expressed as the Ca amino acid salt, e.g., calcium glycinate.
(Tentative WA 2018, Official SA 2018)
Ca-23 — Calcium Chloride
Calcium chloride and its hydrated forms, is the calcium salt of hydrochloric acid and has the formula CaCl₂.
(Official 2014)
Ca-29 — Calcium Citrate
Calcium citrate and its hydrated forms, is the calcium salt of citric acid. Anhydrous calcium citrate has the formula Ca₃(C₆H₅O₇)₂.
(Official SA 2023)
Ca-26 — Calcium Glucoheptonate
Is a complex of glucoheptonic acid and is commonly expressed as Ca glucoheptonate.
(Tentative SA 2017, Official WA 2018)
Ca-25 — Calcium Gluconate
Is a calcium complex of gluconic acid, and is commonly expressed as Ca gluconate.
(Tentative SA 2016, Official WA 2017)
Ca-22 — Calcium EAHP
Is the chelate of any soluble calcium salt and Ethanol, 2-amino-2-hydroxy-1,2,3- propanetricarboxylate.
(Tentative WA 2018, Official SA 2018)
Ca-28 — Calcium Lignosulfonate
Is a complex of calcium (II) salt of lignosulfonic acid.
(Tentative SA 2018, Official WA 2019)
Ca-24 — Calcium Polysaccharide
A complex formed by the reaction of calcium with polysaccharide long chain carbohydrates.
(Tentative 2016, WA; Official 2016, SA)
Ca-19# — Calcium Thiosulfate (fertilizer quality)
Is a product composed principally of CaS₂O₃, which inhibits the ammonia volatilization from urea and urea ammonium nitrate.
(Official 2013)
Ca-4 — Dolomite
Is a material composed chiefly of carbonates of magnesium and calcium in substantially equimolar (1-1.19) proportions.
(Official 1950)
Ca-5 — Ground Limestone (coarse-ground limestone)
Is calcic or dolomitic limestone ground sufficiently fine for effective use as a liming material.
(Official 1950)
Ca-12 — Ground Shell Marl
Is the product obtained by grinding natural deposits of shell marl so that at least seventy-five percent (75%) shall pass a U.S. Standard No. 100 sieve (150 μm opening).
(Official 1989)
Ca-10 — Ground Shells
Is the product obtained by grinding the shells of mollusks so that not less than fifty percent (50%) shall pass a U.S. Standard No. 100 sieve. The product shall also carry the name of the mollusk from which said product is made.
(Official 1950)
Ca-15 — Gypsum, Landplaster or Crude Calcium Sulfate
Is a product consisting chiefly of calcium sulfate with combined water (CaSO₄·2H₂O) and is incapable of neutralizing soil acidity. It may be guaranteed as either CaSO₄ or CaSO₄·2H₂O and shall not contain less than fifty-five percent (55%) CaSO₄ or seventy percent (70%) CaSO₄·2H₂O.
(Official 2011)
Ca-2 — High Calcic Liming Materials
Are liming materials containing at least twenty-five percent (25%) calcium. Further, at least ninety-one percent (91%) of the total calcium and magnesium is calcium.
(Official 1976)
Ca-3 — High Magnesic Liming Materials
Moved. See Mg-2.
Ca-8 — Hydrated Lime
Is a dry material, made from burnt lime, which consists of calcium hydroxide or a combination of calcium hydroxide with magnesium oxide and/or magnesium hydroxide.
(Official 2000)
Ca-21 — Magnesium EAHP
Moved. See Mg-3.
Ca-16 — Magnesium Sulfate
Moved. See Mg-4.
Ca-11 — Marl
Is a granular or loosely consolidated earthy material comprised largely of shell fragments and calcium carbonate precipitated in ponds.
(Official 1958)
Ca-18 — Pelletized Limestone
Is pulverized limestone that has been granulated by the addition of a water-soluble binding agent.
(Official 1996)
Ca-6 — Pulverized Limestone (fine-ground limestone)
Is the product obtained by grinding either calcitic or dolomitic limestone so that all materials will pass U.S. Standard No. 20 sieve (850 μm opening) and at least seventy-five percent (75%) will pass a U.S. Standard No. 100 sieve (150 μm opening).
(Official 1989)
Ca-9 — Quick Lime, Burnt Lime, Caustic Lime, Lump Lime, or Unslaked Lime
Are calcined materials comprised chiefly of calcium oxide in natural association with lesser amounts of magnesium, and which are capable of slaking with water.
(Official 2000)
Ca-13 — Waste Lime (by-product lime)
Is any industrial waste or by-product containing calcium or calcium and magnesium in forms that will neutralize soil acidity. It may be designated by prefixing the name of the industry or process by which it is produced, i.e., gas-house lime, tanners’ lime, acetylene lime-waste, lime-kiln ashes, calcium silicate, etc.
(Official 2000)
