Wither

Necrotic energy fills a target of your choice that you can see within range, draining moisture and vitality from it. The target must make a Constitution saving throw. The target takes a quarter of 10d10 necrotic damage, rounded up, on a failed save, or none on a successful one. This spell has no effect on undead.
If you target a plant creature or a magical plant, it makes the saving throw with disadvantage, and the spell deals double maximum damage to it.
If you target a nonmagical plant that isn't a creature, it doesn't make a saving throw; it simply shrivels up and dies.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d10 for each slot level above 3rd.