Turfgrass Management Terms O
Obtuse - blunt or rounded (apex or base), usually making an angle of more than 90 degrees
Organic – a term used to describe substances that originate from living matter, whether plant or animal, and occur as a result of natural processes. Organic also describes gardening and lawn care styles and products that avoid man-made ingredients
Organic fertilizer - fertilizers that contain carbon, hydrogen and oxygen, as well as needed
Organic matter – nutrient-rich material created as plant and animal matter decomposes. It is an important component to healthy topsoil. Incorporating organic matter, such as leaves, grass clippings, or compost reduces the need to use chemical fertilizers and topdressing organic matter onto soil gives added water-holding capacity and exchange capacity to the soil
Organic soil - general term used in reference to any soil that is at least 20 percent organic matter
Ornamentals – plants used in gardens and landscapes primarily for aesthetics rather than for fruit or other edibles.
Overseed – practice of sowing seed in areas of turf that have become thin due to wear and tear, fill in bare spots, drought, and pest damage. This practice is also used during the cool months on warm-season grasses, including zoysiagrass and Bermudagrass, with cool-season perennial ryegrass for winter color. Overseeding is the easiest and least expensive way to build grass density without replacing it