You imbue limited intelligence to one non-sentient tree or shrub no less than 20 feet tall, allowing you to telepathically communicate simple instructions to the tree. On your command, the tree pulls back its branches and fires a volley of acorns, branches, or other debris at any target that you designate. The tree receives one ranged attack per round and its BAB equals your caster level plus your Dexterity modifier. Its attack deals 1d4 points of damage plus one point of damage per three caster levels and has a range of 30 feet. The tree is immobile, has an AC of 16, and30 hit points. The tree is incapable of defending itself; it only attacks when directed. The spell ends two rounds after you cease concentration or the tree sustains 30 or more points of damage.