A treated cellulosic material comprising a cellulosic material having a porous structure defining a plurality of pores, at least a portion of the pores containing a treating agent comprising a polymer comprising a modified cellulose polymer; and a modifying agent comprising a hydrophobic amine, a metal ion, or a quat. The present disclosure further describes a method for preparing a treated cellulosic material comprising (a) providing a cellulosic material; (b) a first treatment protocol comprising impregnating the cellulosic material with a dispersion comprising a polymer, the polymer comprising a modified cellulose polymer; and (c) a second treatment protocol comprising impregnating the cellulosic material with a modifying agent, the modifying agent comprising a hydrophobic amine, a metal ion, or a quat.