moss growing on trees is an example of what
Moss Choice of substrate varies by species as well. Moss species can be classed as growing on: rocks, exposed mineral soil, disturbed soils, acid soil, calcareous soil, cliff seeps and waterfall spray areas, streamsides, shaded humusy soil, downed logs, burnt stumps, tree trunk bases, upper tree trunks, and tree branches or in bogs. Moss species growing on or under trees are often specific about the species of trees they grow on, such as preferring conifers to broadleaf trees, oaks to alders, or vice versa.[6] While mosses often grow on trees as epiphytes, they are never parasitic on the tree.
Stoma Stomata are present in the sporophyte generation of all land plant groups except liverworts. In vascular plants the number, size and distribution of stomata varies widely. Dicotyledons usually have more stomata on the lower surface of the leaves than the upper surface. Monocotyledons such as onion, oat and maize may have about the same number of stomata on both leaf surfaces.[4]:5 In plants with floating leaves, stomata may be found only on the upper epidermis and submerged leaves may lack stomata entirely. Most tree species have stomata only on the lower leaf surface.[5] Leaves with stomata on both the upper and lower leaf are called amphistomatous leaves; leaves with stomata only on the lower surface are hypostomatous, and leaves with stomata only on the upper surface are epistomatous or hyperstomatous.[5] Size varies across species, with end-to-end lengths ranging from 10 to 80 µm and width ranging from a few to 50 µm.[6]