The Victorian National Party has joined sawmillers and conservationists in calling on the State Government to come clean on the extent of overlogging in the state's native forests. National Party resources spokesman Peter Hall said it was common knowledge in the timber industry that the Department of Natural Resources and Environment had overestimated logging rates by up to 50 per cent in some regions. An industry report circulated in the department has estimated volumes need to be cut 20 per cent to be sustainable.