Plant is a tall, upright perennial with woody stems. Preferred habitat is disturbed soils, road-
side, and the margin of wet sites. Distribution is coastal in the Escambia region.

Leaves are opposite; small; linear to lance-like and widest at the middle; long pointed; short leaf stalks. Base is wedge- shaped; margins are serrate and tapers to the tip with sides being less than equal; occasionally slightly twisted. Upright branches and tiny leaflets emerge from the leaf axil.

Flowers are much branched and nearly flat-topped. Heads are about 1/4 inch long, numerous; bell-shaped; all disc flowers. Styles are filiform and about twice the length of the corolla, which is conspicuous and bluish (photographs lavender). Bracts are green and small. Flowers occur in the autumn.

While the Blue Boneset is usually associated with Ageratum Mist Flower, the two species are separate. The Latin, ivaeifolium or ivifolium, refers to the exceptionally willowy leaf, “slender leaf; thin; in need; starved,” as well as the ivy-like leaf shape.

The plant is known in Mississippi, Alabama and Florida. A specimen collected in 1998 was the first recorded for Alabama.