The Army is moving to dismantle the bulk of its horse units, part of a broader push by service planners to eliminate programs they see as peripheral to the core mission of fighting and training for wars. The Army will begin phasing out five horse-mounted ceremonial units stationed at Fort Irwin , California; Fort Huachuca , Arizona; Fort Riley , Kansas; Fort Sill , Oklahoma; and Fort Cavazos Texas, Steve Warren, a service spokesperson, told reporters Tuesday. The decision impacts 141 horses