In order to investigate the influence of vertical vacuum dyeing method on the green wood of Populus
cathayana, reactive red X-3B was adopted to dye the green wood of P. cathayana by the design of single
factor experiment in this study. The results showed that the dyeing area increased gradually with the rise
of vacuum degree and dye concentration. The dyeing area experienced an increase first and then
decreased along with the rise of vacuum time. With the rise of dyeing time, the dyeing area increased
quickly, then decreased gradually and reached balance. Under the same dyeing process and same wood,
with the rise of wood height, the dyeing area generally decreased first and then increased.