Accepted methods of trading silage, and equipment for measuring it.

Accepted method

Silage is traded by dry measure. The measuring process records the weight of each individual truckload harvested (wet weight), and also takes representative samples for analysis from trucks and silage stacks in order to determine the dry matter percentage of those samples.

Trading Standards works with industry representatives such as Federated Farmers and contractor representatives to ensure that silage sales are conducted using only approved and verified weighing equipment, as required by the Weights and Measures Act.

Equipment for weighing silage

If you're a buyer or seller of maize silage, the equipment you use to determine the quantity of silage must be approved and verified.


We've approved various novel types of weighing systems that can be used in the silage trading industry. You can see these in the approvals database.

Search the approval certificate register

The criteria for approving weighing equipment for trade use involves testing the equipment to ensure in meets a variety of technical performance requirements. The equipment may also have conditions imposed to ensure that when it is in use it doesn't facilitate fraud.

See Applying for a type approval for more information.


Once a type of weighing equipment has been approved, each piece of equipment of that type must still undergo verification testing to ensure it meets the requirements of the approval certificate and is accurate and suitable for its intended purpose.

If you have questions

If you're unsure about your weighing equipment, or if you'd like to discuss getting some equipment approved, get in touch with Trading Standards.

Contact us