Broadleaf signalgrass is a spreading summer annual with a fibrous root system. These plants often root at the lower stem nodes and therefore are commonly found growing along the ground but with tips ascending. Broadleaf signalgrass may reach as much as 3 feet in height. Leaf sheaths are often maroon-tinged and hairy throughout. Leaf blades are without hairs, except for those that occur on the margins. They may also be maroon-tinged, with a fringed membranous ligule. Stems are prostrate, branching and bent at the nodes. Leaf blades are overall short and wide in appearance, approximately 1 1/2 to 6 inches long and 6 to 15 mm wide. Leaf blades are widest near the base and taper to a point. Leaves are rolled in the bud and without hairs on either leaf surface except on margins and in the collar region. Spikelets on the seedhead are somewhat flattened in appearance.
