Fire Seeds

Source fire seeds

Each acorn's damage increases to 1d6 points of fire damage per caster level (maximum 20d6 for all acorns, no more than 10d6 for any particular acorn). Each holly berry's damage increases to 2d6 points of fire damage + 2 points per caster level. Any creature that fails its Reflex save against an acorn or holly berry catches on fire, taking 2d6 points of fire damage each round until the fire is extinguished. Attempts to extinguish this fire use the spell's save DC.