If you sell livestock due to a sever drought, you normally have two years after the year of the "involuntary conversion" to replace the livestock. This year however, you have been given additional time to make the replacement. The notice below not only explains the law, but more importantly shows the counties that qualify for the four-year replacement.
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Notice 2009-81 explains the circumstances under which the 4-year replacement period under section 1033(e)(2) is extended for livestock sold on account of drought. The Appendix to this notice contains a list of counties that experienced exceptional, extreme, or severe drought conditions during the 12-month period ending August 31, 2009. Taxpayers may use this list to determine if an extension is available.