4. Fairchild, D. 1947. The world grows round my door. Charles 9. . 1932. Florida wild life. The Macmillan Co., New York. Scribner's Sons, New York. 347 pp. 199 pp. 5. Krook, L., R. H. Wasserman, J. N. Shively, A. H. Tashjian, T. D. 10. Small, J. K. 1933. Manual of the southeastern flora. Author, Bronx, Brokken and J. F. Morton. 1975. Hypercalcemia and calcinosis in New York. (Reprinted, Univ. North Carolina Press, Chapel Hill, Florida horses: implication of the shrub, Oestrum diurnum, as the N. C. 1953). 1554 pp. causative agent. Cornell Veterinarian 65(l):26-56. 11. Wherry, E. T. 1964. The southern fern guide. Doubleday & Co. 6. Long, R. W. and O. Lakela. 1971. A flora of tropical Florida. Univ. Garden City, New York. 349 pp. of Miami Press, Coral Gables. 962 pp. 7. Nehrling, H. 1944. My garden in Florida. Vol. I. The American NOTE: Dr. Fairchild blamed himself for introducing the rampantly Eagle, Estero, Fla. 422pp. spreading vine, Cissus sicyoides L. (4), and he probably did bring his 8. Simpson, C. T. 1926. Ornamental gardening in Florida. Author, high-climbing strain from Java as a fiber source, but, as far as we know, Little River, Fla. 243pp. this extremely variable, pan tropic species was already growing in Flor ida as a native.

Proc. Fla. State Hort. Soc. 89:353-355. 1976.

GRASSES FOR COASTAL DUNE AREAS

Robert M. Craig Materials and Methods U. S. Department of Agriculture, Every reasonably accessible coastal dune location in Soil Conservation Service, Florida was visited. One hundred fifty-two sites were selected Gainesville, FL 32601 for study. It was felt that these adequately represented the type and extent of coastal dune vegetation in the state. Additional index words, conservation. Information was obtained at each site on soil conditions, Abstract. A detailed study of 152 coastal dune sites type and size of dune area, extent of use by people, domi throughout Florida indicates that several native or naturalized nant and minor vegetation and other pertinent information. plants can be used for vegetating coastal dunes. Grasses The area studied was from the first vegetation above the were found to be the most important plants on the dunes. water inland to the scrub-zone. Unknown plants were identi Their growth habits and adaptability to dune conditions make fied by University of Florida Herbarium personnel. them especially valuable in preventing erosion and for land All observations and determinations were made by visual scaping. Information is given on these grasses such as com estimation. It was decided that a general survey of a wide mon and scientific name, growth form, climatic adaptation, magnitude would yield more applicable information than a methods of propagation and other pertinent facts. smaller number of more detailed studies. The individual studies were then reviewed to determine Over 30 million tourists and residents utilized Florida theuseful grass species in relation to their climatic adapta beaches during 1975. According to Bruce Johnson, Bureau tion, ability to adequately vegetate coastal dunes, and oc of Coastal Zone Planning, (9) the pressures of population currence on specific soil conditions and dune types. and tourist growth make it imperative that state and local governments plan for additional public beaches and beach Results and Discussion access. Ney Landrum, Director of Department of Natural Twenty-five grass species were identified. Table 1 con Resources, Division of Recreation and Parks, (10) reported tains information on the occurrence and dominance of these that the 5 most popular state parks played host to slightly grasses. This paper considers in detail only the 12 grasses over 5 million visitors during the 1975-76 fiscal year. All of that occurred on 5% or more ofthe sites studied. these state parks are along coastal beaches. Two different types of growth form were evident and are This demand on coastal dunes and beaches for recrea the basis for the following plant groups: decumbent and/or tional purposes has already caused serious erosion problems. spreading by rhizomes or stolons; and bunch. In 1973, the Department of Natural Resources determined that at least 200 of the 1200 miles of Florida'scoastline have Decumbent serious erosion problems. This erosion is caused by construc This group includes the grasses that curve upward from tion, structures that have altered the offshore currents and a horizontal or inclined base. They spread by means of inadequate vegetative cover on the dunes. It is obvious that rhizomes and/or stolons. Twelve grasses with this growth these erosion problems will increase unless preventative or habit occur on frontal dunes. Table 1 contains information corrective measures are intensified. on the occurrence and dominance of these grasses. Nine of The problems of coastal dune erosion and its solution these grasses have special significance when considering their through the use of plant materials is recognized by the U. S. use in revegetating coastal dunes. Department of Agriculture, Soil Conservation Service (SCS). Seaoats (Uniola paniculata L.). Seaoats is the most im The SCS Long Range Plant Materials Program for Florida portant and widespread grass on coastal dunes. It occurred (1) gives the highest priority to the solution of this problem. on 85% and was dominant on 81% of the sites studied. It A field study was recently completed to determine the plant occurs throughout Florida on coastal dune sites. The sites species that are naturally adapted for usein vegetating where it did not occur were generally those with excessive coastal dunes. foot traffic. The results indicate that several plants have a high po The leaves are narrow, pale green and die back close to tential for use in dune stabilization work. These plants are the ground each winter in northern locations. The seed discussed in detail by Craig (2, 3 and 4). Grasses are gen heads are compressed spikelets borne at the end of stiff stems erally the most important and noticeable plants of Florida's 3 or more feet in length and mature in the fall. Individual coastal dunes. Their growth habits and ability to adapt to seeds somewhat resemble the common oats of agronomic use. coastal dune conditions make them especially valuable in Rhizomes are relatively few in number and almost as coarse preventing erosion and for landscaping. as the above ground stems.

Proc. Fla. State Hort. Soc. 89: 1976. 353 Table 1. Percentage of occurrence and dominance of native and naturalized grasses on coastal dunes with decumbent and bunch growth habits.

Growth2 %of Sites NE SE W SWW Scientific Name Form Occ* Domx FL FL FL FL

Andropogon glomeratus (Walt.) B.S.P. B 3 0 0 6 0 5 Andropogon martimus Chapm. D 10 3 0 0 38 0 Andropogon virginicus L. B 3 0 3 0 0 7 Cenchrus spp. L. D 24 4 14 29 15 36 Chloris petraea Swartz B 10 0 6 17 0 19 Cynodon dactylon (L.) Pers. D 7 1 6 3 5 12 Dactyloctenium aegyptium (L.) Beauv. B 6 0 3 11 2 10 Distichlis spicata (L.) Greene D 13 4 26 12 5 10 Eleusine indica (L.) Gaertn B 3 0 0 0 2 10 Panicum amarulum Hitchc. and Chase B 36 19 37 23 60 24 Panicum amarum Ell. D 28 10 11 54 5 43 Panicum ciliatum Ell. B <1 0 0 0 2 0 Panicum maximum Jacq. B <1 0 3 0 0 0 Panicum repens L. D <1 0 0 0 2 17 Panicum virgatum L. B 3 0 14 0 0 0 Paspalum vaginatum Swartz D 10 6 11 23 0 7 Pennisetum purpureum Schumach B 3 0 0 6 0 5 Pennisetum setaceum (Forsk.) Chiov B 1 0 0 6 0 0 Spartina patens (Ait.) Muhl. D 41 33 74 29 45 19 Sporobolus domingensis (Trin.) Kunth B <1 0 0 1 0 1 Sporobolus poiretii (Roem and Schult.) Hitchc. B 3 0 3 3 2 2 Sporobolus pyramidatus (Lam.) Hitchc. D 3 0 0 0 0 10 Sporobolus virginicus (L.) Kuntze D 9 0 9 6 0 19 Stenotaphrum secundatum (Walt.) D 4 0 3 9 0 5 Uniola paniculata L. D 86 81 86 94 85 76

ZB= bunch, D= decumbent. yOcc= occurred. xDom= dominant. WNE FL—Atlantic Coast north of Indian River; SE FL—Atlantic Coast south of Indian River; SW—Gulf of Mexico south of Pasco County; W— West of Franklin County.

Studies by Graetz (7) and Seneca (11) show that seed The leaves are smooth and bluish in color. Seed heads germination is not high, and seedling survival is low. Graetz are narrow, compressed and most often sparsely seeded. The (7) recommends that seaoats be established by digging and plant spreads from a very aggressive, scattered system of dividing native plants. The plants should be dug as deeply rhizomes but the stands are rather open. The plants grow as possibly in order to get a portion of the rhizome with to an average height of 3 to 4 feet. each plant. When replanting, the stock should be set at least No viable seed are produced. Propagation must be made a foot in depth and packed in tightly. Local regulations by using a stem with part of the rhizome attached or 8 to 12 should be followed concerning use of seaoats for propaga inch lengths of the rhizome without the above-ground parts. tion. By Florida State Law, it is illegal to pick the seed Graetz (7) recommends planting 4 inches deep in early heads, and local regulations may even be more restrictive. spring. Studies in Texas by Dahl (5) show that bitter Marshhay cordgrass (Spartina patens (Alt.) Muhl.). This panicum is better adapted than seaoats for transplanting. perennial grass is the second most widespread plant on Sandbur (Cenchrus spp. L.). This grass occurred on 25% coastal dunes. It occurred on 44% and was dominant on and was dominant on 4% of the sites studied. It occurs 33% of the sites studied. This grass occurs throughout throughout Florida and is often a dominant plant in dis Florida on coastal dune sites. It was a dominant plant on turbed or heavily used areas. Numerous species occur in 90% of the dunes composed mostly of broken shell and Florida but those most common on coastal dunes are: coquina rock along the northern Atlantic coast. Cenchrus echinatus L., Cenchrus gracillinus Nash., Cen The stems are slender and up to 2 to 3 feet tall. Leaves chrus myosuroides H.B.K., Cenchrus pauciflorus Benth., are rolled inward giving them a rush-like appearance. Seed and Cenchrus tribuloides L. heads are composed of 2 to several compressed spikes at Sandburs are low growing and branching with flat leaf tached to a central axis. Spikes are nearly at a right angle blades. They are easily distinguished from other grasses by to the culm. The grass spreads by means of a network of having stiff, spiny burs. The burs become especially trouble slender rhizomes. Plants grow to an average height of 2 to 3 some to bare feet after they mature. feet. Sandburs are generally not propagated by choice due to Studies by Graetz (7) and Seneca (11) indicate that seed the troublesome burs. This feature would be of value if it can be used for propagation. Based on seedling growth re was desirable to reduce foot traffic. Propagation is by seed sponse studies by Seneca (12), this grass is especially salt ing or use of vegetative material. Seeding by mechanical tolerant. Plantings of vegetative material can also be made means is difficult because the burs tend to adhere to each in early spring with good results. Studies by Garbisch (6) other. suggest using bare-root planting stock for large plantings Seashore saltgrass (Distichlis spicata (L.) Greene). This rather than seeding. Graetz (7) recommends using stems grass occurs primarily on coastal marsh areas but is also rooted at the base, preferably with a section of rhizome at found on low dunes throughout Florida. It occurred on tached and planted at depths of 4 to 5 inches. 13% and was dominant on 4% of the sites studied. It is a Bitter panicum (Panicum amarum Ell.). This perennial dominant plant mostly in southwest Florida on low dunes grass occurred on 30% and was dominant on 10% of the adjacent to the Gulf of Mexico. sites studied. It occurs throughout Florida on coastal dune This low growing perennial grass spreads by means of areas but is especially important in the southern section. extensive rhizomes and occasional stolons. Culms are stiff

354 Proc. Fla. State Hort. Soc. 89: 1976. and 6 to 18 inches tall. Blades are numerous, sharp pointed, have special significance when considering their use in re- 2 to 4 inches long and conspicuously two-ranked. Pure vegetating coastal dunes. stands somewhat resemble common bermudagrass. Shoredune panicum (Panicum amarulum Hitchc. and Propogation is by vegetative methods. The rhizome and Chase). This rather dense upright bunchgrass occurs on stolon pieces root readily and according to Valiela (13), coastal dune areas throughout the state. It occurred on 36% fertilization will initially increase the plant's growth. Use of the sites studied and is a dominant plant at many loca should be limited to the low dunes where moisture condi tions, especially west Florida. tions are relatively favorable. The stems are coarse, straight, stiff and up to 4 feet tall. Gulf bluestem (Andropogon maritimus Chapm.). Sev The leaves and stems are bluish in color. This bluish color eral Andropogon species occur on coastal dunes but the most makes it an especially attractive plant for use in landscaping. important one is gulf bluestem. It occurs only in west Flor The seed head is partially compressed and produces mod ida on coastal dunes adjacent to the Gulf of Mexico. This erate amounts of viable seed each fall. The crown of the perennial grass occurred on 38% and was dominant on 10% plant enlarges slowly from short almost vertical tillers. of the sites studied in west Florida. Viable seed are produced in moderate amounts. The This prostrate or creeping grass spreads by means of low seed should be planted about 1 inch deep and the area creeping rhizomes. It is easily distinguished by the grayish mulched for best results. Seedling survival appears to be color of the leaves and prostrate growth habit. related to adequate rainfall following seed germination. Ob Propagation is by vegetative means and the rhizomes servations in the Carolinas by Graetz (7) show that clumps root readily. It often forms thick stands in the areas back of can be dug, divided and planted with good results during the frontal dunes. It occurs naturally only in west Florida the summer rainy season. but could be used elsewhere if desired. Stiffleaf chloris (Chloris petraea Swartz). This suberect, Seashore paspalum (Paspalum vaginatum Swartz). This perennial grass occured on 10% of the sites studied but was perennial grass occurs as a dominant plant on low dunes or not a dominant plant at any location. It occurred mostly in in wetter areas within the dunes along the Atlantic Ocean. south Florida. It occurred on 10% and was dominant on 6% of the sites This chloris is mainly a bunch grass but does produce studied. some stolons. Culms are 1 to 3 feet tall and strongly com Seashore paspalum is a low, creeping grass that spreads pressed. The numerous leaf blades are folded and 4 to 8 by runners as well as by rhizomes. It resembles common inches long. The inflorescence is composed of 4 to 6 racemes, bermudagrass except for the seed head. There are usually each 2 to 3 inches long. two racemes which are at first erect but spread at maturity. Exact propagation methods are undetermined at this On wetter sites, when it is mowed, the grass makes a very time. It appears that seed, stolons or rooted decumbent dense, flat sod. culms can be used. Morton (8) recommends planting drier areas by trans Crowfoot grass (Dactyloctenium aegyptium (L.) Beauv.). planting bits of sod, firming and mulching. This grass occurs to some extent on coastal dunes through Seashore dropseed (Sporobolus virginicus (L.) Kunth). out peninsular Florida. It occurred on 10% of the sites Seashore dropseed occurs mostly in the southwest sections of studied but mostly in south Florida. the state. It is not a dominant plant on the dunes but did Crowfoot grass is 6 to 18 inches tall and has compressed occur on 9% of the sites studied. culms. It spreads by rooting at the nodes on the ascending This low growing, perennial grass spreads by means of ends of the culms. The spikelets are short with 3 to 4 spikes. extensive rhizomes and occasional stolons. Culms are stiff Exact propagation methods are undetermined at this and 6 to 18 inches tall. Leaves are numerous and 2 to 4 time. It appears that seed or culms can be used. inches long. Extensive colonies, with few flowering culms, occur in wetter areas within the coastal dunes. Pure stands somewhat resemble common bermudagrass. Literature Cited Propagation is by vegetative methods. Rhizome pieces 1. Austin, W. E. 1974. Long Range Plant Materials Program—Florida. root readily. Use should be limited to the low dunes where U. S. D. A., Soil Conservation Service, Gainesville, Florida. Pg. 27. moisture conditions are more favorable for good growth. 2. Craig, R. M. 1974. Coastal Dune Vegetation. Proc. Florida State Hort. Soc. 87:548-552. Common bermudagrass (Cynodon dactylon (L.) Pers.). 3. . 1974. Natural Vegetation on Florida's Coastal Dunes. This bermudagrass occurs to some extent on coastal dunes Proc. Soil and Crop Science Soc. of Florida 34:169-171. throughout Florda. It occurred on 7% of the sites studied 4. . 1975. Woody Vegetation for Coastal Dune Areas. Proc. but was a dominant plant only along the northeast coast on Florida State Hort. Soc. 88:428-434. 5. Dahl, B. E. 1975. Vegetation for Creation and Stabilization of low dunes. Foredunes. Texas Coast. Estuarine Research Vol. 11. Academic It is a low growing, creeping grass that spreads exten Press, Inc. New York. Pg. 457. sively by means of scaly rhizomes or flat stolons. The flower 6. Garbisch, E. W. 1975. Biotic Techniques for Shore Stabilization. ing culms are usually erect with 4 or 5 spikes. Estuarine Research Vol. 11. Academic Press, Inc. New York. Pg. 405. 7. Graetz, K. E. 1973. Seaside Plants of the Carolinas. Univ. North Propagation is by vegetative means or seed. The rhizomes Carolina, Sea Grant Publication UNC-SG-73-06. Pg. 22, 25, 27, 30. or stolons root readily. Seed can be purchased commercially 8. Morton, J. F. 1973. Salt Tolerant Silt Grass (Paspalum vaginatum). and seeding is an effective method to establish this grass. Proc. Florida State Hort. Soc. 86:482-499. Seeding is an especially effective method in recreation areas 9. Shields, H. W. 1976. Inventories Reflect Need for Facilities. Fla. Cons. News, Vol. 11, No. 11:2. where some management practices can be used. 10. . 1976. State Parks Continue to Attract Millions. Fla. St. Augustine grass (Stenotaphrum secundatum (Walt.) Cons. News, Vol. 11, No. 12:4. Kuntze). This lawn grass occasionally occurs on coastal 11. Seneca, E. D. 1969. Germination Response to Temperature and dunes under natural conditions. Good management, includ Salinity of Four Dune Grasses from the Outer Bank of North Carolina. Ecology 50(l):45-53. ing irrigation and fertilization, is needed for good growth. 12. . 1972. Seedling Response to Salinity in Four Dune Bunch Grasses from the Outer Banks of North Carolina. Ecology 53(3): This group includes the grasses that grow in a distinct 465-471. clump. Thirteen grasses with this growth habit occur on 13. Valiela, I. 1975. Production and Dynamics of Salt Marsh Vegetation and the Effects of Experimental Treatment with Sewage Sludge frontal dunes. Table 1 contains information on the occur Biomass Production and Species Composition. /. Appl. Ecol 12* rence and dominance of these grasses. Three of these grasses 973-981.

Proc. Fla. State Hort. Soc. 89: 1976. 355