"Tree Saleswoman" is not an official name. It may have been referenced by ids5621 as such, but has not been officially named. Alternatively, it may be a name popular among fans, but has no official basis.
The Tree Saleswoman is an unnamed Matoran who sells Christmas trees that was harassed by Visto for killing trees. She later appeared in Jevik? playing poker at Bawl's Sacks.
Nothing is really known about the character. She was rather calm while being harassed by Visto, but acted rather violent towards Myto when trying to make conversation while they were playing poker together at Bawl's Sacks.