ASSOCIATION OF AMERICAN PLANT FOOD CONTROL OFFICIALS (AAPFCO)
PLANT & MEDIA PRODUCTS (PMP)
 

PMP-1 — Biochar

Is a solid material obtained from thermochemical conversion of biomass in an oxygen-limited environment (pyrolysis) containing at least 60% carbon. Feedstocks may be composed of crop residue, wood or forest waste, and animal manures. Materials treated in salt water, antifreeze, or treated with preservatives are not permitted. When listing biochar as an ingredient statement, the feedstock shall be designated by prefixing the term biochar with the feedstock from which it was produced, i.e. poultry litter biochar, green waste biochar, papermill biochar, etc. When more than one feedstock is involved, all feedstocks greater than 10% of the total volume are to be listed in decreasing volume. Their uses include soil amendments.
(Official 2016, WA)

PMP-2‡ — Biosolids (Sewerage Sludge)

A primary organic solid material produced by wastewater treatment (Sewerage Sludge) processes that can be beneficially recycled for its plant nutrient content and soil amending characteristics.
(Official 2013)

PMP-3‡ — Compost

Is the product manufactured through the controlled aerobic biological decomposition of biodegradable materials. The product has undergone mesophilic and thermophilic temperatures, which significantly reduces the viability of pathogens and weed seeds, and stabilizes the carbon, such that it is beneficial to plant growth. Compost is typically used as a soil amendment, but may also contribute plant nutrients.
(Tentative SA 2017; Official WA 2018)

PMP-4‡ — Digestate

Is the liquid or solid material processed through anaerobic digestion. Labeling digestate materials shall be designated by prefixing the name of the feedstock from which it is produced, i.e. cow manure digestate, biosolids digestate, etc.
(Official 2011)

PMP-5‡ — Earthworm Castings

Are excreta of earthworms produced in a controlled environment and consist primarily of the digested material passed by the worms.
(Official 2006)

PMP-6 — Forest Products

Untreated wood and its untreated byproducts generated from the harvest of timber. These products may include lumber, saw dust, bark and similar materials but do not include reprocessed wood from fabricated consumer or industrial products.
(Official 2002)

PMP-7β — Fulvic Fraction

The extracted portion of humic substances that are soluble in both alkali and acidic aqueous solutions.
(Official 2015, SA)

PMP-8 — Humates

Are the salt(s) of humic acid(s).
(Official 2013)

PMP-9β — Humic Acids

Are the portions of the alkali-extracted humic substances that are insoluble in strongly acidic solutions. They will precipitate from the alkali extract in acid solutions of pH 2 or less. They can be used as either soil amendments, foliar applications, or blended with liquid fertilizers. 
(Official 2013)

PMP-10 — Humic Substances

Constituents of soil organic matter and the aquatic environment, consisting of complex heterogeneous mixtures of carbon-based substances formed by biochemical reactions during the decay and transformation of plant and microbial remains. They are primarily composed of three main fractions, called humic acids, fulvic acids, and humin, which are operationally defined by their solubility in dilute alkali and acid solutions. Sources of humic substances are commercially harvested from terrestrial deposits which include, but are not limited to, leonardite, oxidized lignite, oxidized sub-bituminous coals, humalite, carbonaceous shales (including humic shale), peat, and sapropel.
(Tentative SA 2018; Official WA 2019)

PMP-11 — Humus

A material that is used for soil conditioning and is derived primarily from the decomposition of plant and animal matter in such manner that the material is not recognizable. It shall have a conductance of less than 5.5 millimhos/centimeter (5.5 mmho/cm) and a pH in the range of 3.7 to 7.5 as determined by the saturated paste method.
(Official 2003)

PMP-12 — Peat

Is partly decayed vegetable matter of natural occurrence. It is composed chiefly of organic matter that contains some nitrogen of low activity.
(Official 1951)

PMP-13‡ — Vermicompost

Is earthworm castings that have undergone non-thermophilically biological oxidation and stabilization.
(Official 2006)

PMP-14 — Zeolites

Are micro porous, aluminosilicate minerals which possess a high cation exchange capacity. Their uses include Soil Amendments.
(Official 2014)