A sketch of Louisiana Irises by Caroline Dormon
The infinite variations in Louisiana irises is one of the most amazing things ever observed in any group 'of plants. As to the form of the flowers, orchids show more diversity; but the color-range is un-surpassed in any genus. And this applies to them as they were found growing in their native habitat. 
Iris fulva, discovered in 1812, is a well established species. It is easily recognized, for flowers, foliage, and fruit are quite distinctive. It is more widely distributed than any species in this group, and occurs from North Arkansas to South Louisiana. In its more northerly habitat, it varies little, with small rust-red, drooping flowers, and a very rare yellow form. In Central and South Louisiana, the flowers are larger, and colors are varied, ranging from rich red to shrimp-pink. 

Louisiana Iris species iris.nelsonii growing int he wild near Abbeyville, LA

As part of my interest in Louisiana irises, I have been collecting the wild forms and species. My first attempt to collect an Iris nelsonii was a trade with a friend who had gotten the iris through an iris supplier. That plant looked like a red hybrid between I giganticaerulea and I.fulva. The fulva- giganticaerulea crossings end up intermediate with an open form and usually a rich purple or a dark purple. Usually the flower has a line signal and no halo or spray of white around the yellow signal, which is typical of giganticaerulea falls as well as the falls of I brevicaulis.

My son Benny, Jr. and I have encountered many types of wildlife while searching for irises in the wild. Some are beautiful and harmless like herons, wood ducks, pileated woodpeckers, deer, indigo buntings, and blue birds, to name a few. Others are in another category, like alligators and poisonous snakes. We both have had water moccasins strike at us and miss, but Benny, Jr. has had the closest calls.

A picture of two flowers of iris hexagona found in Florida by Benny Trahan Jr

Iris.hexagona  is the one Louisiana species that I have not observed anywhere in Louisiana. The reason I ventured on a two week search for irises throughout Florida was curiosity stimulated by what I read in the Society's Fiftieth Anniversary publication of 1991.Throughout the small book, especially in articles by Dr. John K. Small reprinted from the 1930s, Florida cities and towns were mentioned as the location of many of the then-designated species of irises.

These irises are now classified as I. hexagona, although some do recognize I. hexagona savannarum as a separate variety within the species I hexagona. (I.savannarum was one of the old, discarded species names). Even though all the East Coast irises are today considered to be i.hexagona, there had to have been sufficient variety among them to induce Small to extend several different species designations.

Iris fulva painted by John Audubon

The Louisiana Irises belong to a group of iris species native to the American South.

The first species within this grouping to be officially described was Iris hexagona, recorded by Walter in 1788.  Hence the group is today known as the Series hexagonea.