Q. Do we need a cost basis for the timber?
A. No. Cost basis for timber is usually zero. Unless, you know, for a fact, that the decedent was carrying a cost basis, for the timber. In that case, you would not have a zero basis, and would be allowed a step up to market value, which would result in no capital gain.
Timber basis is not the cost of the property. For a discussion on Timber Basis, see
https://www.extension.purdue.edu/extmedia/FNR/FNR_FAQ_2.pdf
