Abstract: An advanced analysis on the basis of the power equation that previous burning need proposed by Rothermel R.C. indicates that in this equation the power of water loss can be expressed as follows Qm=Mf°(376.812+509.5595ki) Here Mf is water content, ki is the ratio of 1 and water loss strenght. On the basis of computing the need power of water loss of the forty woodplants,the authors have found that hard burning arbor species are Idesia polycarpa, Platycarya serobilacea, Taxus chinensis, Crataegus prinnatifida, Corylus heterophylla, Koelreuteria paniculata and Populus tomentosa induding some brush species such as Elaeagnus pungens, and Malus hupehensis. The power value which they need is greater than 7600 kJ/kg.