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.
Albugo The thick-walled oospores are the main overwintering structures, but the mycelium can also survive in conditions where all the plant material is not destroyed during the winter. In the spring the oospores germinate and produce sporangia (s. sporangium) on short stalks called sporangiophores that become so tightly packed within the leaf that they rupture the epidermis and are consequently spread by the wind. The liberated sporangia in turn can either germinate directly with a germ tube or begin to produce biflagellate motile zoospores. These zoospores then swim in a film of water to a suitable site and each one produces a germ tube - like that of the sporangium - that penetrates the stoma. When the oomycete has successfully invaded the host plant, it grows and continues to reproduce.