from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A brown amorphous substance found in decaying vegetation.
from the GNU version of the Collaborative International Dictionary of English
- n. A brown amorphous substance found in decaying vegetation. Cf. humin.
from The Century Dictionary and Cyclopedia
- n. A name given to various substances which are present in vegetable mold, peat, etc.
- n. A brown substance produced by the action of strong acids or alkalis on various organic bodies, especially by heating treacle or alcohol with strong sulphuric acid, thoroughly washing the residue with water, then triturating it with gum, and drying the mixture.
Mulder, it is composed of a number of organic bodies, and he has identified the following substances -- ulmin, humin, ulmic, humic, geic acids, &c.
-- After extracting the peat with solution of carbonate of soda, it still contains ulmin or humin.
They are formed when the alkalies or their carbonates act on ulmin and humin, or upon ulmates or humates of lime, iron, etc. Their dilute solutions are yellow, or brown.
The substance exuding from the bark is called ulmin.
Resources of the Southern Fields and Forests, Medical, Economical, and Agricultural. Being also a Medical Botany of the Confederate States; with Practical Information on the Useful Properties of the Trees, Plants, and Shrubs
Cerato-ulmin, a wilting toxin of Ceratocystis ulmi: development of antiserum against the toxin
At one particular stage of the process it is converted into one or other of two substances, called humin and ulmin, both insoluble in alkalies, and apparently identical with the insoluble humus of the soil; but when the decomposition is more advanced the products become soluble in alkalies, and then contain humic, ulmic, and geic acids, and finally, by a still further progress, crenic and apocrenic acids are formed as the result of an oxidation occurring at certain periods of the decay.