Modifies a noun

• acid: Humic acids have been long proven to enhance nutrient uptake at the root zone.

• substance: Humic substances formed during the composting of organic matter.

• soil: North of this wall, the immediately underlying deposit was a dark humic garden soil.

• silt: The feature was then partially backfilled with several backfills of bone-rich friable humic silts, interleaved with redeposited subsoil probably from episodic collapse.

• deposit: Subsequently, F64F was filled with a series of bone-rich humic deposits, which contained assemblages of domestic and craft-working refuse.

• content: The high magnetic susceptibility and humic content indicate the presence of abundant, highly divided occupation debris.