VOL. XXXI OCTOBER, 1930 No. 370 JOURNAL OF THE NEW YORK BOTANICAL GARDEN IRIS STUDIES IN THE GULF STATES JOHN K. SMALL BEARDLESS IRIS AND IRIS SPECIES ETHEL ANSON S. PECKHAM A "BIG TREE" SECTION REACHES THE GARDEN E. D. MERRILL PLANT ECOLOGY COURSE STARTED FORMAN T. MCLEAN NOTES, NEWS, AND COMMENT ACCESSIONS PUBLISHED FOB THE GARDEN AT LIME AND GREEN STREETS, LANCASTER, PA. THE SCIENCE PRESS PRINTING COMPANY Entered at the post-office in Lancaster, Fa., as second-class matter. Annual subscription $1.00 Single copies 10 cents Free to members of the Garden THE NEW YORK BOTANICAL GARDEN BOARD OF MANAGERS HENRY W. DE FOREST, President JOSEPH P. HENNESSY HENRY DE FOREST BALDWIN, Vice President CLARENCE LEWIS F. K. STURGIS, Vice President ADOLPH LEWISOHN JOHN L. MERRILL, Treasurer D- T- MACDOUGAL E. D. MERRILL, Secretary £ENNET?„^ MACKENZIE EDWARD D. ADAMS £ARKER MCCOLLESTER r „ „ H. DE LA MONTAGNE, JR. CHARLES P. BERKEY BARRINGTON MOORE MARSTON T BOGERT J PIERPONT MORGAN GEORCE b. BREWSTER LEWIS RUTHERFURD MORRIS N. L. BRITTON H HOBART PORTER NICHOLAS MURRAY BUTLER HENRY H. RUSBY ROBERT W. DE FOREST GEORGE J. RYAN THOMAS A. EDISON MORTIMER L. SCHIFF CHILDS FRICK EDMUND W. SINNOTT R. A. HARPER SAM F. TRELEASE JAMES J. WALKER, Mayor of the City of New York WALTER R. HERRICK, President of ihe Department of Parks SCIENTIFIC DIRECTORS R. A. HARPER, PH. D., SC. D., Chairman D. T. MACDOUGAL, PH. D., LL. D. CHARLES P. BERKEY, PH. D, SC. D. BARRINGTON MOORE A. B„ M. F. ,.-,.„,„ -r •• c r, T T T^ HENRY H. RUSBY, M. D., SC. D. MARSTON T. BOGERT, SC. D., LL. D. GEORGE T RYAN| LL D NICHOLAS MURRAY BUTLER, PH. D., EDMUND W. SINNOTT, PH. D. LL. D., LITT. D. SAM F. TRELEASE, PH. D. DIRECTOR EMERITUS N. L. BRITTON, PH. D., SC. D., LL. D. GARDEN STAFF E. D. MERRILL, SC. D Director-in-Chief MARSHALL A. HOWE, PH. D., SC. D Assistant Director JOHN K. SMALL, PH. D., SC. D Head Curator of the Museums A. B. STOUT, PH. D Director of the Laboratories P. A. RYDBERG, PH. D Curator H. A. GLEASON, PH. D Curator FRED J. SEAVER, PH. D : Curator ARTHUR HOLLICK, PH. D Paleobotanist BERNARD O. DODGE, PH. D Plant Pathologist FORMAN T. MCLEAN, M. F., PH. D Supervisor of Public Education JOHN HENDLEY BARNHART, A. M., M. D Bibliographer PERCY WILSON Associate Curator PALMYRE DE C. MITCHELL Associate Curator SARAH H. HARLOW, A. M Librarian H. H. RUSBY, M. D Honorary Curator of the Economic Collections ELIZABETH G. BRITTON Honorary Curator of Mosses MARY E. EATON Artist ROBERT S. WILLIAMS Administrative Assistant E. J. ALEXANDER Assistant Curator ALBERT C. SMITH, A. B Assistant Curator CLYDE CHANDLER, A. M Technical Assistant MARJORIE E. SWIFT, A. M Assistant Pathologist ROSALIE WEIKERT Technical Assistant KENNETH R. BOYNTON, B. S Head Gardener G. L. WITTROCK, A. M Docent H. M. DENSLOW, A. M., D. D Honorary Custodian of Local Herbarium ROBERT HAGELSTEIN Honorary Curator of Myxomycetes E. B. SOUTHWICK, PH. D Custodian of Herbaceous Grounds ETHEL ANSON S. PECKHAM. Honorary Curator, Iris and Narcissus Collections JOHN R. BRINLEY, C. E Landscape Engineer WALTER S. GROESBECK Clerk and Accountant ARTHUR J. CORBETT Superintendent of Buildings and Grounds JOURNAL OF The New York Botanical Garden VOL. XXXI OCTOBER, 1930 No. 370 IRIS STUDIES IN THE GULF STATES Opportunity was afforded last spring for a more thorough than usual study of the native irises of the Gulf States. Attention was devoted largely to the two main iris centers of that region, namely, Florida and Louisiana. However, the Florida iris fields being fairly well known, only limited time was devoted to them, but further observations were made on the seven species native in that state. Seasonally, the irises of Florida fall into two groups—early- flowering and late-flowering. The first group contains five spe­ cies, Iris Carolina, I. savannarum, I. Kimballiae, I. rivularis, and I. Albispiritus; the second comprises two species, Iris hexagona and I. tripetala. In the peninsula, in mid-March, the iris season was well under way, in some places nearly over. However, our main object was accomplished, namely, the photographing and collecting of Iris Albispiritus. In northern Florida, the plants representing the second season had not yet come into flower. Reports from the Mississippi Delta led us to hasten to our headquarters in New Orleans. The remarkable natural iris fields discovered in southern Loui­ siana in 1925 have been visited by the writer several times pre­ vious to this year, for short periods. The discovery was a mere incident, en route, on a botanical trip from Florida to western Texas. The iris display between Lake Pontchartrain and New Orleans was so unusual that several plants were packed in passing and mailed to the Garden. These flour­ ished in the cold frames and flowered the following spring. Each succeeding spring, up to and including this year, brought more Louisiana iris plants to the Garden plantations. In 1926, 237 238 flP^^I ^W^L^S^M! IHKH M* # ; JHII ^Hs^^^^^v^^l^^^^^^^^B ill *jrj«^^ el "V SP f > 1» 1, 1* « ' / * *filisMf1MB 1 Iii/uBSrirW : yiBltftllll £&e FIGURE I.—In the flatwoods along Twelve-mile Creek near the Caloosa- hatchee, Florida. Iris Albispiritus growing along a pool. This white- flowered iris inhabits the flatwoods on both sides of the Caloosahatchee. Photo by W. M. Buswell. 239 240 1927, and 1928 comparatively few plants were added to the grow­ ing collections, but much was learned about the habitats and habits of these irises cf the lower Mississippi Delta. In the spring of 1929 extensive collections were made and additional plantations were established in New Jersey, Maryland, and Florida. In the meantime it was learned that these irises native in the gumbo near the mouth of the Mississippi were hardy in the cli­ mate of the latitude of New York and that they flourished in the ordinary soils of that region. Enough material had been assembled and studied to indicate the magnitude of the iris development in the vicinity of the mouth of the Mississippi River. Fortunately for our iris studies, the past spring (1930), curi­ ously enough, following a very severe winter, was especially fav­ orable, for the flowering season lasted for a period of two months. The plants flowered profusely. Mr. Alexander and the writer spent six weeks in continuous field work about New Orleans and at several localities remote from that city. We are indebted to numerous friends resident in that region for their helpful coop­ eration. At least 8000 plants were sent to the Garden and to other co­ operating northern plantations in which southern irises are being given a trial. These are intended, along with those collected in former years, for study, hybridizing, and propagation, and ulti­ mately, in large part, for distribution to other iris plantations in America and in the Old World. Mr. Alexander's color notes and descriptions based on sepals, i.e., the color of the blade and of the crest, indicate some 200 dis­ tinguishable forms, which may be summarized as follows: six various shades of violet-blue, with about fifteen different combinations of crest and color; four various shades of lavender-blue, with about twelve differ­ ent combinations of crest and color; eleven various shades of violet, with about forty different com­ binations of crest and color. seventeen various shades of red-violet, with about thirty-five different combinations of crest and color; fourteen various shades of lilac, with about twenty-five differ­ ent combinations of crest and color; 241 242 243 nine various shades of cerise and magenta, with about eighteen different combinations of crest and color; fifteen various shades of pink and old-rose, with about twenty different combinations of crest and color; twenty-six various shades of red, orange-red, and orange, with about thirty-five different combinations of crest and color. The flower and fruit of one of the new species discovered in the spring of 1925 was published in 1927,1 as Iris vinicolor. This was one of the "red"-flowered kinds. Its publication re­ sulted in the sending of thousands of miscellaneous iris plants from the vicinity of New Orleans, through the state inspection office, to many parts of the United States, and there is no telling how many were "bootlegged" out of. the State of Louisiana. The publication of six additional new species, Iris violipurpurea, f. giganticaerulea, I. chry so phoenicea, f. miraculosa, I. chrysaeola, and /. atrocyanea, in 1929,2 resulted in further drafts on the fields of southern Louisiana. There, seemingly large depredations have had no visible effect on the iris fields, the richest of which lie in the immediate vicinity of New Orleans, so far as is at present known. We are safe in assuming that they have not been so dis­ astrous to the natural growth of iris there as has been the growth of the city for two centuries. The number of plants destroyed and perhaps the kind of species exterminated through the drain­ age and filling of the city will never be known. At the present stage of the study nearly fifty species and a num­ ber of natural hybrids are indicated. Our usual criterion for assigning the status of species is an isolated colony, persisting through propagation by rootstocks and an annual accretion of seedlings without any variation in the characters of the perianth. This remarkable local development of iris in the tip of the Mississippi Delta is as yet inexplicable. Aside from its magni­ tude, the outstanding points are the often vast colonies of species, the great range and combination of colors, and the unusual size of the plants.