humic

This deposit, if obtained from light brown peat, is ulmic acid; if from black peat, it is humic acid.
Peat and its Uses as Fertilizer and Fuel|Samuel William Johnson
A small portion of nitrogen unites with hydrogen, forming ammonia, which remains combined with the humic and other acids.
Peat and its Uses as Fertilizer and Fuel|Samuel William Johnson
This solvent separates the humic and ulmic acids from the undecomposed vegetable fibers.
Peat and its Uses as Fertilizer and Fuel|Samuel William Johnson
In such soils humic acids are present and the requisite alkalinity is thus awanting.
Manures and the principles of manuring|Charles Morton Aikman

We are well aware that the nitrogen present in the humic matter of the soil is readily nitrifiable.
Manures and the principles of manuring|Charles Morton Aikman

British Dictionary definitions for humic

humic

/ (ˈhjuːmɪk) /

adjective

of, relating to, derived from, or resembling humushumic acids

Word Origin for humic

C19: from Latin humus ground + -ic

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