The bill, if passed, would allow timber owners to claim a tax deduction for the loss of uncut timber from fire, storm, theft, or other casualties. It specifies appraisal methods for calculating the deduction and excludes timber not held for sale. The bill also requires reforestation of the lost timber within 5 years and allows recapturing the benefit of the deduction if reforestation is not completed. The effective date would apply to losses sustained in taxable years after the bill's enactment.