Spring Tune-up on IoH Regulations! 2018

Thought with frozen road declarations ending in zones 4 and 5 and recent questions on IoH, a bit of spring tune-up on IoH regulations may be helpful as machinery gets ready to roll.

First, a reminder of what vehicles are defined as Implements of Husbandry or IoH. (see full definition below). A recent contact learned after being ticketed that IoH used for non-agricultural purposes lose their exemptions including all vehicle dimensions.

The IoH categories are important when determining when permits are needed for weight and length based on local road decisions.  A quick way to check local requirements is  available here: https://datcpgis.wi.gov/maps/?viewer=ioh

The No Fee Permit has not been changed.  Time for getting permits into  road authorities before spring field work is getting short.   Here’s the link to permit applications and information.  http://wisconsindot.gov/Pages/dmv/agri-eq-veh/ag-prmts.aspx   The response to the question “what if I don’t get a permit for my overweight or overlength IoH or AgCMV?” hasn’t changed. Those vehicles in a crash are not operating legally on the road.

The map of prohibited bridges and roads will be updated on March 1.  That information can be found at http://wisconsindot.gov/Pages/dmv/agri-eq-veh/ag-prmts.aspx   Remember posted bridge weights have to be followed – there are no exemptions even for IoH Category B.

The sunset date was removed. The current laws are in place until new legislation and not seeing that anytime soon.

For further information the WI DMV has moved agricultural information to “DMV Info” from their homepage at: wisconsindot.gov

Additionally, fyi.uwex.edu/ioh is available as a resource.

Definition s.340.01 (24)(a) Wis. Stats

The definition of an Implement of Husbandry reads:

Subject to par. (b), “implement of husbandry” means all of the following:

  1.  A self-propelled or towed vehicle that is manufactured. designed or reconstructed to be used and that is exclusively used in the conduct of agricultural operations.  An  “implement of husbandry” may include any of the following:
  • Farm tractor (Referred to as Category A).
  • Self-propelled combine, self-propelled forage harvester; self-propelled fertilizer or pesticide application equipment but not including manure application equipment; towed or attached tillage, planting, harvesting, and cultivation equipment and its towing farm tractor or other power unit; to which it is attached; or another self-propelled vehicle that directly engages in harvesting farm products, directly applies fertilizer, spray or seeds but not manure, or distributes feed to livestock. (Referred to as Category B).
  • A farm wagon, farm trailer, grain cart, manure trailer, or trailer adapted to be towed by, or to tow or pull, another implement of husbandry (Referred to as Category C).
  1. A combination of vehicles in which each vehicle in the vehicle combination is an IoH or in which an IoH is towed by a farm truck, farm truck tractor,  motor truck, or agricultural commercial motor vehicle.

Looking forward to spring!


Cheryl A. Skjolaas
Agricultural Safety Specialist
UW Madison/Extension Center for Agricultural Safety and Health
460 Henry Mall, Madison WI 53706
ph: 608-265-0568