Wand of Plant Destruction

This wand of petrified wood has 7 charges. While holding it, you can use an action to expend up to 3 of its charges to harm a plant or plant creature you can see within 30 feet of you. The target must make a DC 15 Constitution saving throw, taking 2d8 necrotic damage for each charge you expended on a failed save, or half as much damage on a successful one. The wand regains 1d6 + 1 expended charges daily at dawn. If you expend the wand's last charge, roll a 1d20. On a 1, the wand shatters and is destroyed.