I do not have the book, and I was not sent the stats. I was faking it until the two combatants could actually affect each other.
The scorpions appear at 65n35e and 60n35e, and step forward to 65N40E and 60N40E. One of the scorpions actually hits with a claw (natural 20), but the other five attacks miss (best roll 20). The tree takes 1 point of damage. It has 66 HP remaining.
Round 611
The tree whips each scorpion with two tentacles, inflicting much more damage than either can take, and making them both disappear.