US SB1141

Amends Internal Revenue Code Section 165(b) to allow timber owners to claim casualty loss deductions based on appraised fair market value rather than cost basis for uncut timber destroyed by fire, storm, theft, wood-destroying insects, invasive species, or severe drought

Requires appraisals to be completed within 1 year of the casualty loss by a Federal- or State-certified appraiser conforming to Uniform Standards of Professional Appraisal Practice (USPAP)

Applies only to timber held for sale in an active trade or business (not passive activities), and includes pre-merchantable timber in the definition of eligible uncut timber

Mandates reforestation of affected land within 5 years through planting, seeding, or site preparation, with recapture of tax benefits if requirement is not met

Applies to losses sustained in taxable years beginning after enactment; allows taxpayers to file estimates on initial returns and amend once appraisals are completed