Rachis to a short segment of the rachis. This is significant in the history of agriculture, and referred to by archaeologists as a "brittle rachis", one type of shattering in crop plants. Rachis Rachis is a biological term for a main axis or "shaft" (from the Greek "ράχις, backbone, spine"). In vertebrates a "rachis" can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the "rachis" usually forms the supporting axis of the body and is then called the spine or vertebral column. "Rachis" can also mean the central shaft of pennaceous feathers. In the
Calamus Creek (Wisconsin) with drumlins and scattered muck deposits. Soils are predominantly well drained silt over calcareous sandy loam till." The original vegetation cover is primarily white oak, black oak, bur oak, marsh and sedge meadow, wet prairie, and lowland shrubs. Calamus Creek is part of the larger Upper Rock River Basin. The of the streams comprising the Calamus Creek watershed cover , or 19315 acres, with 54.39 acres covered by five unnamed lakes and 3627.39 acres of wetlands. The watershed includes extensive wetlands, some of which are in the process of restoration. Parts of Calamus Creek are designated wadable nursery waters for