Based on the spelling, I'm guessing you'd like to know about thehumus that's present in soil. If not, typing in "What ishummus?" in the white bar at the top of the webpage w
…ill giveyou the answer you're looking for! Humus can be defined as the organic layers that are abovethe mineral soil horizons . The layers are split into threedevelopmental layers (LFH): Litter, Fermentation and Humus. Litter: (upper layer) contains fallen material like leaves,twigs and needles. There is no decomposition at this level, and itis very easy to recognize individual pieces of material. Fermentation: (middle layer) Partially decomposed material resideshere, although you may be able to make out parts of a twig or aleaf on occasion. Often, you can see threads of fungal hyphae fromdecomposing fungi or small microorganisms like insects. Humus: (bottom layer) You cannot identify plant material asit is too decomposed here. The layer instead is black and greasywith organic matter. There are 3 broad categories of Humus: Mor: Found: higher elevations, usually coniferous forests Climate: moist and cool Litter (L): thick, little breakdown of organic material Fermentation (F): fungal mycelia is matted Humus (H): Yes (abrupt transitions between LFH layers) Moder: Found: mid-elevations, deciduous and coniferous forests Climate: moderate L: moderate to thick F: fungal mycelium loose H: Yes (gradual transition between LFH layers) Mull: Found: low elevations, grasslands and/or very dry forests Climate: warm, dry L: thin F: Thin to none H: often not present (MORE) 
