Pertaining to ulmin; designating an acid obtained from ulmin. (adjective)
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Use "ulmic" in a sentence
"The terms ulmic and humic acids do not refer each to a single compound, but rather to a group of bodies of closely similar appearance and properties, which, however, do differ slightly in their characteristics, and differ also in composition by containing more or less of oxygen and hydrogen in equal equivalents."
"It is highly probable that a certain quantity of potash in the soil may exist in combination with humic and ulmic acids, forming insoluble potassium humates and ulmates."
"The second class of substances formed are _soluble organic acids_, such as _humic_ and _ulmic acids_."