Keen Sight and Smell. The owlbear has advantage on Wisdom (Perception) checks that rely on sight or smell.

Branch. Melee Weapon Attack: +5 to hit, reach 60 ft., one creature. Hit: 5 (1d4 + 3) piercing damage.

Stone. Ranged Weapon Attack: +1 to hit, range 30 ft./120 ft., one target. Hit: 4 (1d6 + 1) bludgeoning damage.

Throw. The Grotesque Tree throws a creature, who it grabs, 60ft. That creature must make a DC 13 Dexterity saving throw, taking 10 (3d6) bludegeoning damage on a failed save, or half as much damage on a successful one.

Snare trap. If the Grotesque Tree hits a creature with a melee attack, it can use a Bonus Reaction to grab that creature. That creature must make a DC 13 Dexterity saving throw or DC 13 Strength saving throw. If this throw fails, the Grotesque Tree grabs the target and holds it 20 ft up in the air. At the start of the next turn the Grotesque Tree draws in the creature up to 10 ft. The Grotesque Tree can grab up to 2 creatures.