This type of trenchers is another type of chain trencher. A tractor-mount trencher is a trenching device which needs a creeping gear tractor to operate. Ditches are dug manually or by a trencher. A wheel trencher or rockwheel is composed of a toothed metal wheel. A trencher installs an unperforated pipe followed by a synthetic or organic wrapped perforated pipe. She served it in a trencher hollowed out of a stale loaf. The cornered cap evolved into today's square trencher or mortarboard university hat. The mortarboard may also be referred to as a trencher cap (or simply trencher). The trencher was a large flat piece of either bread or wood. Another alternative was the trencher, a large flat piece of either bread or wood. It is also sometimes termed a square, trencher, or corner-cap. He hunts down people, collecting their farts and killing them until he comes across Trencher. The first production trencher rolled off the assembly line in 1949. A micro trencher is a "small rockwheel" specially designed for work in urban area.