Southwest Highways March 2013 | Page 20

Southwest Plants: Bluebonnets

19 Southwest Highways & Fields

Lupinus plattensis inhabits the sandy Panhandle, where it is also called Dune Bluebonnet or Nebraska Lupine. Texas is in its southernmost range, but it is more common north of Texas as far as Montana. It is the only bluebonnet in the state that is perennial rather than annual. It grows to about two feet tall, with the familiar palmate leaves and tall flower spikes. Its flowers are much lighter blue than the other species, and it has a dark spot on the face rather than a white or yellow spot. In Texas there is another species of lupine, which could be considered a sixth state flower species, Lupinus perennis, the Wild Lupine. It has palmate leaves like other lupines but with 7-11 leaflet fingers, and its flowers can have tinges of white, pink, blue or purple. This plant has a huge range covering most of the United States, but because of slight differences in attributes in different areas of its range, it is often broken into separate species, including Lupinus nutallii, Nutall’s Lupine with its narrow leaflets, L. diffusus, Spreading Lupine, and L. villosus, Hairy Lupine, both having leaves without fingers, and L. polyphyllus which lives in the northwest and northeast parts of the country. L. plattensis may be a subspecies of this same lupine. In nature some bluebonnets, especially this wild lupine, can produce whiter, pinker, redder, or more purple flowers, but they are not very common. The seeds of those plants bearing these colors are sometimes collected and bred separately to create specific flower colors, but these are not genetically modified, just selectively bred.

In Texas there are also a number of species of legumes that look similar to bluebonnets. The scurfy peas (or scurfpeas) in particular have similar fingered leaves and bluish flower spikes. But while their rosettes may be confused with bluebonnets, their flowers just don’t look the same. When I first found a lone scurfy pea rosette on my central Texas property, I assumed it was a bluebonnet with large leaves, and later when it bloomed I thought it must be a mutant bluebonnet—its flowers were more closed and purple and on a bare stalk. When I found a second one I realized that I had a completely different genus of flowers.

Lupinus concinnus

-Norman G. Flaigg

Wildflower Center Slide Library

Lupinus plattensis

-C.A. Rechtin

Wildflower Center Slide Library