Depreciation. For a decedent's estate, the depreciation deduction is apportioned between the estate and the heirs, legatees, and devisees on the basis of the estate's income allocable to each.
For a trust, the depreciation deduction is apportioned between the income beneficiaries and the trust on the basis of the trust income allocable to each, unless the governing instrument (or local law) requires or permits the trustee to maintain a depreciation reserve. If the trustee is required to maintain a reserve, the deduction is first allocated to the trust, up to the amount of the reserve. Any excess is allocated among the income beneficiaries and the trust in the same manner as the trust's accounting income. See Regulations section 1.167(h)-1(b).
http://www.irs.gov/instructions/i1041/ch02.html#d0e3247
Scroll down to Depreciation and Depletion for example.
http://taxmap.ntis.gov/taxmap/pubs/p559-003.htm
