Sphagnum such gemmae. Peat moss can be distinguished from other moss species by its unique branch clusters. The plant and stem color, the shape of the branch and stem leaves, and the shape of the green cells are all characteristics used to identify peat moss to species. "Sphagnum" taxonomy has been very contentious since the early 1900s; most species require microscopic dissection to be identified. In the field, most "Sphagnum" species can be identified to one of four major sections of the genus—classification and descriptions follow Andrus 2007 (Flora North America): The reciprocal monophyly of these sections and two other minor
Types of plant oils means of extracting essential oils. In this process, used, for example, to extract the onion, garlic, wintergreen and bitter almond essential oil, the plant material is macerated in warm water to release the volatile compounds in the plant. Types of plant oils Plant oils or vegetable oils are oils derived from plant sources, as opposed to animal fats or petroleum. There are three primary types of plant oil, differing both the means of extracting the relevant parts of the plant, and in the nature of the resulting oil: Vegetable fats and oils are what are most commonly called vegetable oils.