This species prefers dry, sandy soil and has escaped from cultivation to roadsides and pastures throughout the state. It has become a weed in some of the eastern states, and I have seen large colonies of it in Indiana in sandy soil in pastures. It is difficult to eradicate and, for this reason, should be exterminated as soon as it is detected. It is commonly called butter and eggs.
Indiana Coefficient of Conservatism: C = null, non-native
Perennial, 3-8 dm, colonial by creeping roots; lvs very numerous, pale green, 2-5 cm נ2-4 mm, narrowed below to a petiole-like base; fls numerous in a compact spike, yellow with orange palate, 2-3.5 cm, including the spur; fr round-ovoid, 8-12 mm; seeds winged; 2n=12. Native of Europe, established in fields, roadsides, and waste places throughout temperate N. Amer. May-Sept. (L. linaria)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.