Darker-colored wood species usually have highervalues, many of which are endangered and underprotection. Chemical stains and finishes might alsoachieve similar color shades, but customers prefernon-chemical alternatives. Thermal treatment (TT)is one of the low-toxicity choices. It could producedarker shades and enhance some materialproperties but requires a large initial investmentand is time-consuming. This study aimed toevaluate a new type of TT: Surface ThermalTreatment (STT). White Ash, Yellow Poplar, and RedOak were selected and treated on a heated pressat varying temperatures and times. Artificial NeuralNetwork (ANN) was employed to model therelationship between temperature, time, and colorchange. Results demonstrated that STT can achieveefficient thermal modification. The combination oftemperature and duration brought differentshades to all 3 species. Application of the ANNmodel can simulate the process results fast with ahigh degree of accuracy (R2 =0.96)
