Conversion of lignocellulosic materials, including wood, to fuel is currently cost prohibitive due to the expenses involved and the lack of value addition, even though small-diameter hardwoods are readily available. Alternative processes therefore need to be investigated. Partially hydrolyzing wood may offer an opportunity to add value to the conversion process by producing a modified woody by-product that can be used as a wood composite raw material. Experiments were conducted on the effects of a partial hydrolysis on the mass loss, specific modulus, and surface free energy of modified southern hardwoods, and this article reports the changes in holocellulose content of water-saturated yellow-poplar (Liriodendron tulipifera L.), sweetgum (Liquidambar styraciflua L.), and red oak (Quercus spp.) heated at 150°C for 30 minutes in three solutions: 1 percent sulfuric acid, deionized water, and 1 percent sodium hydroxide. The treated woods were compared with untreated controls. The previously tested wood samples were ground to a size 20 mesh, and holocellulose content was analyzed gravimetrically. Properties of the modified wood were then regressed on holocellulose content following partial hydrolysis. All three treatments significantly reduced the holocellulose content in each species, with the greatest reduction obtained in the acid treatment, followed by the alkaline solution treatment and the deionized water treatment, respectively. The changes in holocellulose explained a majority of the variation in mass loss due to treatment and specific modulus, whereas surface free energy was poorly explained by changes in the wood structure. Implications for wood composites manufacturing are discussed.