ASSOCIATION OF AMERICAN PLANT FOOD CONTROL OFFICIALS (AAPFCO) OFFICIAL FERTILIZER DEFINITIONS
MULTI NUTRIENT PRODUCTS (MNP)

MNP-1 — Basalt

Is a common fine-grained igneous volcanic rock. In its finely ground state where 20 percent passes a 100 mesh sieve, it is a source of secondary and micro nutrients.
(Official 2014)

MNP-12 — Carbonaceous Marine Shale

Black shale containing greater than 4% total carbon derived from marine sediment that may contain Ca, Mg, Co, Fe, Mn, and Ni.
(Tentative SA 2024)

MNP-4 — Compost Extract

Is the water extract of compost and may contain suspended material.
(Official 2010)

MNP-2 — Herbivore Insect Frass

Is the excreta of plant-eating insects which is produced in a controlled environment and consists primarily of the digested material passed by plant-eating insects. It is a source of nitrogen, phosphate, and potash.
(Official 2014)

MNP-7β — Kelp Extract

The soluble fraction (which may be concentrated by evaporation) remaining from the chemical or enzymatic digestion of kelp or from nondigestive treatments resulting in isolation of the soluble portion, including, but not limited to, cold-pressing or hydrolysis. This ingredient is a nutrient source and/or a soil amendment. If the extraction agent is a source of nutrients (e.g., potassium hydroxide), it shall be included in the derivation statement.
(Tentative SA 2021, Official WA 2022)

MNP-11 — Plant Extract

Is a substance resulting from the processing (physical or otherwise) of plant tissue. After concentrating, the resulting substance is a source of plant nutrients and/or organic compounds. The definition is used by prefixing a term with the name of the plant(s) from which the extract is derived.
(Tentative SA 2023, Official WA 2024)

MNP-3 — Polyhalite

The naturally occurring mineral from sedimentary marine evaporates, which is a hydrated sulfate of potassium (K), calcium (Ca), and magnesium (Mg) having the formula K₂Ca₂Mg(SO₄)₄·2H₂O. Containing not less than thirteen percent (13%) soluble potash (K₂O), three percent (3%) magnesium (Mg), eleven percent (11%) calcium (Ca), and eighteen percent (18%) sulfur (S).
(Tentative WA 2017, Official SA 2017)

MNP-10 — Potato Extract

Delete.
(WA 2024)

MNP-9 — Seabird Guano

Is the fecal excrements from marine birds. Seabird guano has an organic matter content greater than 40%, is a source of nitrogen (N) and available phosphate (P₂O₅).
(Tentative WA 2022, Official SA 2022)

MNP-6β — Seaweed Extract

The soluble fraction (which may be concentrated by evaporation) remaining from the chemical or enzymatic digestion of seaweed or from nondigestive treatments resulting in isolation of the soluble portion, including, but not limited to, cold-pressing or hydrolysis. This ingredient is a nutrient source and/or a soil amendment. If the extraction agent is a source of nutrients (e.g., potassium hydroxide), it shall be included in the derivation statement. 
(Tentative SA 2021, Official WA 2022)

MNP-5 — Vermicompost Extract

Is the water extract of vermicompost and may contain suspended material.
(Official 2006)

MNP-8 — Volcanic Ash

Composed of small amorphous fragments deposited from the gaseous cloud during an explosive volcanic eruption. Deposits contain ≥45% SiO₂. When at least 25% passes a 100 mesh sieve, it is a source of nutrients and soluble silicon.
(Tentative WA 2022, Official SA 2022)