Amco Manufacturing
Offers tools for primary tillage, such as disk harrows, ditchers, levee plows, terrace plow, and bedding hippers. Includes products and dealers.
http://www.amcomfg.com/

B.W. Implement Company
A family owned and operated business that was established in 1948. We manufacture quality farm implements, specializing in seedbed preparation, orchard maintenance, ditchers, and bed shapers.
http://www.bwimp.com

Steiger Manufacturing, Inc.
Makes Toreq line of towed, heavy duty earth scrapers (front dolly, direct mount; high flotation); ditchers; laser trailers; custom manufacturing. Minnesota, USA.
http://grantnelson00.tripod.com/steigermfg/