VANCOUVER -- The B.C. government says medical marijuana companies won't be able to take advantage of a property tax break that was designed for agriculture.

Mayors in B.C. have been raising concerns that marijuana growing operations could set up on expensive industrial land and then ask to be taxed as farmland.

The classification could dramatically reduce those companies' property taxes, in some cases by tens of thousands of dollars.

The province says it plans to exempt medical marijuana operations from the agricultural tax designation beginning in the 2015 tax year.

In April, new federal rules took effect that moved medical marijuana production to licensed commercial growers.

There are currently five operators in B.C. that have been approved by Health Canada, but the federal government has received hundreds of applications.