Wood ash (plant ash)

Ash from burning firewood or other plant material, a fine alkaline powder that retains the plant's minerals.

Characteristics

Retains the calcium, potassium, magnesium and trace elements of the burnt material.
Lower liming value than limestone, but faster acting.
Composition varies with the species and plant part burnt.
Cited as an optional mineral ingredient in traditional biol and bokashi recipes.

Role in the preparation: Acts as a mineral and alkaline component that adjusts pH in fermented preparations and compost.

Caution: Wait until it is completely cold, sift out unburnt pieces, store it dry in a closed container and handle it with gloves, goggles and a dust mask.

Sources: Oregon State University Extension - Use fireplace ash sparingly to boost garden soil · UNH Extension - Guide to Using Wood Ash as an Agricultural Soil Amendment · Argentina.gob.ar - Impulsan el uso de abonos liquidos fermentados

Documentary information: this is neither a recommendation for use nor a plant-protection or veterinary claim. Check your country's regulations before any use.