Brushfire

A small cloud of hot glowing ash fills a 5-foot-radius, 40-foot-high cylinder centered on a point within range. The ashes set alight small patches of fire on the ground. Until the spell ends, dim light fills the cylinder and the area is lightly obscured. 

When a creature enters the spell's area for the first time on a turn or starts its turn there, the hot ash sears it from every direction, even getting inside any unsealed ears, mouth, nostrils, etc. The creature must make a Constitution saving throw. It takes 2d12 fire damage on a failed save, or half as much damage on a successful one.

On each of your turns after you cast this spell, you can use an action to move the cylinder up to 60 feet in any direction, as the fire burns out in its current area and ashes blow to a new location.

Flammable non-magical objects that are not worn or carried are subject to the damage and may ignite.

Fire-adapted Plants of size Large or greater are immune to damage from this spell, and fire-adapted Plants of size Medium or smaller have resistance to this damage and advantage on any saves. The heat from this spell does not penetrate more than a few inches of loose earth, allowing certain Plants to regrow afterwards.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d12 for each slot level above 2nd.