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HomeMy WebLinkAboutProc. Fla. State Hort. Soc. 97, 1984Table 1. Incidence of woody plant species within 2-yr-old plantations of Leucaena leucocephala, Conocarpus erectus, and Acacia auriculiformis. Tree species Ficus aurea L. leucocephala K8 cultivar L. leucocephala K28 cultivar A. auriculiformis C. erectus (0 4 4) (1.7) (0.0) 6.3 (2.9) (0.6) (0.6) Mean no. of invasive woody plants/8 m2 quadrat (SD)a Schinus terebinthifolius Baccharis halimifolia volunteer Leueaena leucocephala 0.3 0.0 9.0 8.7 6.7 (2.3) (5.0) 0.0 1.3 (2.3) 1.0 (1.0) 0.0 1.3 (1.5) 1.0 (1.0) 0.0 zEach value is the mean of 3 quadrats, 8 m2 each in area. Values in parentheses are standard deviations. native, both are aggressive and are found commonly in dis- turbed areas, underscoring the fluidity of the term "weed." It is also noteworthy that the relative abundance of volun- teer leucaena, where encountered, was numerically very close to the groundsel tree and that neither volunteer leu- caena nor groundsel tree were as abundant as strangler fig or Brazilian pepper tree under these experimental con- ditions (Table 1). Although the data generated in this study clearly show very little weed potential for leucaena, it should be stressed that both the K8 and K28 cultivars are relatively "domesti- cated" forms of leucaena. It would not be reasonable to ex- pect similar results from "wild" forms of leucaena and it is also quite possible that different cultural conditions than those used in the current study might have yielded different results. Nevertheless, the results of this work indicate very low weed potential for the K8 and K28 cultivars of leucaena when grown under biomass cultivation conditions. Literature Cited 1. Long, R. W. and O. Lakela. 1971. A flora of tropical Florida. Uni- versity of Miami Press, Coral Gables, Florida. 2. Morton, J. F. 1976. Pestiferous spread of many ornamental and fruit species in south Florida. Proc. Fla. State Hort, Soc, 89:34B-353. 3, Patterson, J. and G. Stevenson. 1977. Native trees of the Bahamas. Jack Patterson, Hope Town, Abaco, the Bahamas. 4, Ruskin, F. R. 1979. Tropical legumes: resources for the future. National Acad. Sci., Washington, D.C. 5. U.S. Dept. Agr. 1971. Common weeds of the United States. Dover Publications, Inc., New York. 6, Vietmeyer, N. and B. Cottom. 1977. Leucaena: promising forage and tree crop for the tropics. National Acad. Sci., Washington, D.C. Proc. Fla. State Hort. Soc. 97:241-244. 1984, NOBODY LOVES THE BISCHOFIA ANYMORE JULIA F. MORTON Morton Collectanea, University of Miami, Coral Gables, FL 33124 Additional index words. Bischofia javanica, bishopwood. Abstract. The bishopwood tree (Bischofia javanica Blume) was introduced and promoted by E. N. Reasoner and Dr. Henry Nehrling who greatly admired a large specimen at Reasiner's Royal Palm Nurseries, Oneco. Dr. Charles Torrey Simpson spoke well of the tree in 1914 but in his book, Ornamental Gardening in Florida (1926), he wrote: "It seems to be an excellent host for a smutty scale and now I am trying to destroy it by girdling but it refuses to die." Despite this warning, the tree was widely sold as an ornamental after WW 1I. Soon it became obvious that the tree becomes too big too soon; is not only subject to scale and leaf spot, but has aggressive surface roots; fruiting branches successively die back leaving holes in the crown; seedlings volunteer in cultivated and natural areas. Removal and disposal of over- grown trees is troublesome and costly, but the wood should be salvaged, being durable in water and excellent for docks and piling, and it is useful as firewood. The bishopwood tree, Bischofia javanica Blume (syns. B. trifolia Hook.; Andrachne trifoliate Roxb.) is a member of the widespread and largely sinister family, Euphorbiaceae. Proc. Fla. State Hort. Soc. 97: 1984. Among its few alternate names in English are: Java cedar, red cedar, West Indian cedar and vinegar wood. In India, it is called paniala, kainjal, boke, joki and several other dia- lectal names. In Malaya, it is nira or thirippu; in Burma, tayokthe; in Samoa, oa; in Fiji, tongogongo, no-ghor or koka (1, 2, 4, 5, 9, 10). Description The tree is fast-growing, erect, to 60 ft, with cylindrical trunk to 12 ft in circumference. The bark is light -brown to grayish, shallowly and narrowly fissured, the surface readily flaking. Evergreen in humid climates, deciduous in areas of low rainfall, the alternate, spirally -set leaves have rather rubbery petioles up to 7 inches long, flattened on the upper - side, tinged with maroon at the base and apex, and the blade is divided into 3 (or sometimes 4-5), leathery, elliptic or obovate, pointed, recurved leaflets, to 6 inches long and 3 inches wide, irregularly saw-toothed, dark -green above, paler beneath, with conspicuous veins and midrib, the latter flat and white on the upper surface, tinged maroon beneath. Petiolules are more or less maroon -tinted, the lateral ones are very short and the terminal up to 3 inches long. Old leaflets turn orange before they fall. Male and female flowers are borne on separate trees. The blooms are very small, 5-parted, pale -green or green- ish -white, profuse, in loose axillary panicles or racemes. Fruits are round, to 3/8 inch wide, brown -scurfy, with juicy, greenish flesh, in pendent strands from 4 inches to 4 ft 241 • F.g. 1. Bishopwood (Bischofia javanica Blume) has trifoliate leaves with finely toothed leaflets, sprays of tiny flowers, and bunches of brown - skinned, spherical, juicy fruits. (Photo by Julia Morton). Origin and Distribution Bishopwood is native to the Chinese provinces of Kwangtung, Fukien, Kweichow, Yunnan and Hupeh; also to Burma, India, the Andaman Islands, Malaysia, tropical Australia and Polynesia (2, 13, 21). In India, it is said, "Where tigers abound, they are usually found clearing their claws by digging them into the soft, astringent bark of the paniala. Inhabiting swamps, river banks and moist locali- ties, the paniala, as its very name suggests, is a tree that grows where there is plentiful moisture." "The paniala can stand shade and moderate frosts, but no drought. It can struggle through weeds characteristic of moist localities. The tree ood healthy shoots." 'The coppices well and throws up paniala can be easily propagated by means of transplants pis cocherelli); coconut scale Aspi t_ raised from seed in nurseries. (8). Throughout its natural Florida red scale (Chrysompha u.s aonidum). (11, C. Dowl- range it may occur from sea level to an altitude of 5,000 ft ing and G. Gwin, Bur. Plant Inspection, personal com- and is often associated with teak (21). In southern Florida, munications). On the honeydew excreted by scale insects the rainfall is sufficient to satisfy the tree on non -swampy, there develops the sooty mold that offended Dr. Simpson. well -drained limestone as well as on sand and marl. Other pests commonly found on this tree are the Keys white - fly (Aleurodicus dispersus), mealy bugs, and thrips (G. History and Status in Florida Gwin, Bur. Plant Inspection, personal communication). In Asia, the tree is sometimes attacked by a small boring beetle The tree was introduced by E. N. Reasoner and planted that penetrates to the heartwood (12). at his Royal Palm Nurseries at Oneco (16). It was first mentioned in the Proceedings of the Florida State Horti- cultural Society in a paper by Charles Torrey Simpson pre- sented at the 25th Annual Meeting of May 14-16, 1912. He referred to it as "A rapid -growing tree with handsome tri- foliate leaves which flourishes finely here." (18). Reasoner merely listed it among tropical trees for southern Florida in his paper at the 27th Annual Meeting in 1914 (17). He wrote the famed plantsman, Dr. Henry Nehrling, that it was a tree of "great beauty" and "an ideal shade tree." Dr. Nehrl- ing visited the nursery and was greatly impressed by the tree. He reported that he was "at once struck by its distinct beauty, its outstanding individuality and its fine form"; that "it was one of the most beautiful, one of the densest and noblest exotic trees" it had ever been his good fortune to see. He planted a specimen at his Palm Cottage Gardens in its rowth disappointingly open and leggy but Gotha, found g it proved hardy. "The heavy freeze in early February, 1917, only killed back some of its branches and it soon fully re - at Naples but it died fromlanted a waterlogging.seedlingHrecommended in its in length (3, 5, 10, 14). They are considered edible in Fiji. Tlside, light -brown, mall,sglossy, averaging wedge-shaped g 2,50 p roundeder oz. (8) planting as a "shade and avenue tree in extreme southern Florida." (16). It was planted in Miami and must have been distributed by the United States Department of Agriculture, for there was a 20-ft tree at the Agricultural Station in Bermuda in 1915 (6) and one over 60 ft high at the Agricultural Experi- ment Station in Mayaguez, Puerto Rico, in 1923 (7). By 1926, Dr. Simpson was disenchanted. In his book, Ornamental Gardening in Florida, he wrote: "It seems to be an excellent host for a smutty scale and now I am trying to destroy it by girdling but it refuses to die. It might make a shade tree for roads but I think we have much better ones." (19) . Nevertheless, Gaines B. Wilson, of Miami, in a paper presented before the 50th Annual Meeting of the Florida State Horticultural Society in 1937, included Bischofia javanica among the trees in his "Recommended and Proven List", as "Handsome, dark green glossy foliage. Introduced dense with head years agobutrarely+ planted" (24). Sturrock and Menninger included Bischofia javanica in their Shade and Ornamental Trees for South Florida and Cuba (1946) (22), and Nixon Smiley had nothing negative to say of it in his chapter on Shade Trees in Subtropical Gardening in Florida (1951) (20). In fact, this tree was actively promoted by nurserymen and landscapers over the several years of rapid real estate development immediately after World War II. Growing Awareness of Undesirability Gradually, it became apparent that the tree is a prime host for several foliage diseases and pests. Inspectors from the Florida State Division of Plant Industry's Bureau of Plant Inspection have recorded leaf spot diseases caused by Phyllostica sp. and Cercospora bischofiae Yamamoto, and green scurf, or algal leaf spot, caused by Cephaleuros vires- cens Kunze (23). They have also identified heavy infestations of tessellated, or palm, scale (Eucalymnatus tessellates); pyri- form scale (Protopulvinaria pyri f ormis); oleander scale (Phenacaspis cocherelli); false oleander scale (Pseudaulacas- d`ntus destructor), and Fig. 2. The bishopwood tree is a prime host for several foliage diseases and pests, and sooty mold develops on honeydew excreted by scale insects. (Photo by Julia Morton), Proc. Fla. State Hort. Soc. 97: 1984. 242 In addition, it became evident that the tree was out- growing its allotted space in home gardens, that it has ag- gressive, far-reaching surface roots; also that branches that bear fruit die back and in succeeding years other branches fruit and die back, leaving large gaps in the crown, and the tree becomes progressively more unsightly. Topping the tree and rapid regrowth produce a temporary improvement until the resumption of the branch fruiting -and -dying cycle. Eventually the property owner cuts the tree down entirely and, like Dr. Simpson, must take drastic steps to overcome vigorous sprouting from the stump. 1 Fig. 3. An 11-year-old bishopwood tree with one-half bearing heavily. The leaves on the bearing branches are yellowish; on the non -bearing branches, deep -green. (Photo by Julia Morton). Another serious disadvantage of the bishopwood tree is that its fruits are eagerly consumed by migrating robins and the resulting bird -distribution of seeds gives rise to volun- teer seedlings, especially in hedges and shrubbery of culti- vated grounds, but also as invaders in hammocks and other natural areas (15). Further, apart from its nuisance aspect as a weed, the tree seems to have harmful properties. In the past few years veterinarians have been reporting illness in several dogs and cats that have chewed on the foliage of small specimens with- in their reach. No experienced, responsible nurseryman would grow the tree today. Unfortunately, there are newcomers in the land- scape trade who seeks fast-growing trees of any kind and avail themselves of any left -over stocks of this species to achieve "instant" effects in new housing and commercial develop- ments. The property owner finds out too late that he has acquired an undesirable tree and a disposal problem. One unhappy householder in Cooper City reported that two bishopwood trees planted by the builder's landscape con- tractor 12 ft from the house and 4 ft from the driveway had reached 25 ft in height in 3 yr and surface roots were "spreading in all directions". Such a situation is common and the householder has no recourse but to bear the cost of having the trees taken out and the disappointment and cost of having to replace these trees with suitable species properly located. The tree should never have been adopted for landscaping. Proc. Fla. State Hort. Soc. 97: 1984. Fig. 4. Upper branches of this large bishopwood tree, receiving most light, have fruited heavily, a few at a time, over the years and have died successively. The tree is an ugly sight and a massive disposal problem. (Photo by Julia Morton). Potential Economic Uses The main asset value of the bishopwood tree is as a source of useful timber. It is cultivated in India, Burma, Taiwan (12), East Africa and South Africa (21) for its wood which somewhat resembles black walnut (12) but has a strong vinegar odor when freshly cut. The heartwood is dull red -brown, close -textured, usually with a wavy grain; hard, strong, medium -heavy (45 lb/ft3), medium durable indoors or out and especially under water. It is employed for piling, bridges, boats, wells, railway sleepers, buildings, furniture, carving and pencils (2, 5, 10, 12, 21). Durability is extended by preservative treatment but the heartwood is non -absorbent. When creosoted, sleepers last 15 yr, other- wise only 4-5 yr. The wood is easy to work and takes a good polish. It does not warp if kiln -dried. Air -drying must be gradual, else it may warp and crack (2). Some local woodworkers are al- ready taking advantage of the available wood when these trees are cut down and are pleased with bowls and other objects made from it. It is to be hoped that this utility will provide an additional incentive for removing bishopwood trees from cultivated and wild areas. Branches unwanted for carpentry should be salvaged for fuel. When thoroughly dry, the wood burns with intense heat (William Graves, Univ. of Fla. AREC, Homestead; personal communication). Medicinal and other folk uses The astringent leaf juice is applied on sores in India (5). In Fiji, the leaf is eaten or the leaf decoction is imbibed to relieve tonsilitis (1). Japanese investigators report an ascorbic acid content of 136 mg/ 100 g (2). The bark contains 16% tannin and yields a brown dye commonly used in Samoa for making designs on tapa cloth (9). In Fiji and the New Hebrides, the bark is boiled in salt water and placed on cuts. The inner bark is rubbed on urticaria caused by stinging hairs of nettle-like plants (1), [probably Laportea spp.] 243 Conclusion The bishopwood is another example of the many mis- takes made in the past in introducing and utilizing exotic fast-growing trees for landscaping in South Florida. These mistakes are being repeated to the detriment of the property owner, the community and the environment. It is time for nursery and landscaping professionals to promote the ideal of quality and suitability, rather ecies for pthan just speed of plant- ing. It1isin time echoice for Southf Florida landscaping to maturation ad Literature Cited 1. Altschul, S. 1973, Drugs and foods from little-known plants. Harvard Univ. Press, Cambridge, Mass. 2. Anonymous. 1948, Wealth of India: Raw Materials. Vol. I. Goun. Sci. & Indus. Res., New Delhi. 3. Backer, C. A. and R. C. Bakhuizen van den Brink, Jr. 1963. Flora of Java (Spermatophytes only), Vol. I. N. V. P. Noordhoff, Gronin- gen, The Netherlands. 4. Bailey, F. M. 1902. The Queensland flora. Pt. V. H. J. Diddams Co., Brisbane. 5. Benthall, A. P. 1946. Trees of Calcutta and its neighborhood. Thacker Spink & Co. (1933) Ltd., Calcutta. 6. Britton, N. L. 1918. Flora of Bermuda. Charles Scribner's Sons, New York. 7. Britton, N. L. and P. Wilson. 1923-24. Botany of Porto Rico and the Virgin Islands. Vol. 5, Pts. 1-4, New York Acad. Sci., New York. 8. Chaturvedi, M. D. 1958. Where there's water, there's the paniala. Indian Fanning 8(7):13. 9. Christopherson, E. 1935. Flowering plants of Samoa. Bul. 128, Bernice P, Bishop Museum, Honolulu, Hawaii. 10. Dastur, J. F. 1951. Useful plants of India and Pakistan, 2nd ed, D. B. Taraporevala Sons & Co., Ltd., Bombay. 11. Dekle, G. W. 1976. Arthropods of Florida and neighboring land areas. Vol, 3: Florida armored scale insects. Florida Dept, Agr., Div. Plant Industry, Gainesville, Fla. 12. Howard, A. L. 1951. A manual of the timbers of the world, Macmil- lan & Co., Ltd., London. 13. Lee, S. 1935. Forest botany of China. Commercial Press, Ltd., Shanghai. 14. Long, R. W. and O. Lakela. 1971. A flora of tropical Florida. Univ. of Miami Press, Coral Gables, Fla. 15, Morton, J. F. 1976. Pestiferous spread of many ornamental and fruit species in South Florida. Proc. Fla. State Hort. Soc. 89:348-353. 16. Nehrling, H. 1944. My garden in Florida and miscellaneous horti- cultural notes, Vol. 1. The American Eagle, Estero, Fla, 17, Reasoner, E. N. 1914. Flowering trees for Florida. Proc. Fla. State Hort. Soc. 27:170.171. 18. Simpson, G. T. 1912. Native and exotic. Proc. Fla. State Hort. Soc. 25:184. 19. Simpson, C. T. 1926. Ornamental gardening in Florida. Published by the author, Little River, Fla. 20, Smiley, N. 1951, Subtropical gardening in Florida, Univ. of Miami Press, Coral Gables, Fla. 21. Streets, R. J. 1962. Exotic forest trees in the British Commonwealth. Clarendon Press, Oxford, England. 22 trees for South Florida and eCuba. Stuartnninger. Daily Shade DailyN News, Inc., Stuart, Fla. 23. Wehlburg, C., S. A. Alfieri, Jr., K. R. Langdon, and J. W. Kim- brough. 2975. Index of plant diseases in Florida. Bul. 11. Fla. Dept, Agr. & Consumer Serv., Div, Plant Industry, Gainesville, FL. 24. Wilson, G. B. 1937. Shade tree planting in southern Florida. Proc. Fla. State Hort. Soc. 50:65, Proc. Fla. State Hort. Soc. 97:244-247. 1984. ANTHRACNOSE OF ACACIA IN FLORIDA: OCCURRENCE AND FUNGICIDAL CONTROL' E. L. BARNARD Divisions of Forestry dr Plant Industry, FDA CS, P.O. Box 1269, Gainesville, FL 32602 R. A. SGHRoEDER Division of Forestry, FDACS, 3125 Conner Boulevard, Tallahassee, FL 32301 Additional index words. Acacia cyanophylla, Colletotrichum gloeosporioides, Glomerella cingulata. Abstract. Several species of Acacia are grown in Florida as ornamentals. In recent years, more than a dozen reports e d of Gloeosporium sp. and/or Colletotrichum sp., with anthracnose-like symptoms on at (east three Acacia spp., have appeared in the files of Florida's Division of Plant In- dustry. An additional report has been located in the filClinic. of the University of Florida Extension Plant Pathology ports are from Brevard, Charlotte, Highlands, Lee, Martin, Orange and Palm Beach Counties. An isolate of the pathogen from Acacia cyanophylla in Highlands County has been identi- fied as Glomerella cingulata (anamorph = Colletotrichum gloeosporioides); the anthracnose pathogen apparently parent) New re- sponsible for damage to Acacia spp. in Japan, lC- o- ntribution No. 570. Bureau of Plant Pathology. Trade names are used in this article solely to provide specific information. Mention of a trademark or proprietary product does not constitute a guarantee Inrestry and/or Plant warranty imply its roduct by the Divisions of approval to the exclusion ofoother products that may also be suitable. Guinea, and India. Inoculations have proven the patho- genicity of this isolate to A. cyanophylla; providing the first confirmation of anthracnose of acacia in Florida. Trials indi- cate control may be achieved with a number of fungicides. Chlorothalonil appears most effective. The nearly pantropical genus, Acacia Mill. (Legumino- sae, subfamily Mimosoidae), is comprised of ca. 800 species of shrubs and small trees (8). Acacia spp. are used for timber, tannin, soil reclamation, windbreaks, fuel, conservation, and sometimes even cattle fodder where grazing is scarce (3, 8). Many species are used as ornamentals also, due in part to their often showy flowers. In the United States, acacias are grown as ornamentals in several warmer areas including the west coast, Hawaii, and southern Florida. Few diseases significantly affect the use of acacias as ornamentals. However, losses of up to 90% of nursery seedling crops of A. dealbata Link. to anthracnose infections [diseases "having characteristic limited lesions, necrosis, and hypoplasia, generally caused by one of the Melanconiales", sensu 1-Iawksworth et al. (6)] have been reported in Japan (7, 14). Indeed, anthracnose of acacia has been included in a listing of internationally dangerous forest tree diseases (14). Ito and Shibukawa (7) originally described the anthracnose pathogen as Physalospora acaciae Ito & Shibukawa (ana- morph = Colletotrichum acaciae Ito & Shibukawa). The organism was later determined by Terashita (13) to be synonymous with Glomerella cingulata (Stonem.) Spaulding & Schrenk (anamorph = C. gloeosporioides (Penz.) Sacc.). Apparently, G. cingulata is responsible for damage to Acacia spp. in Spain, New Guinea, and India (l, S) as 'wen. -Mena (9), however, described a serious foliage disease of A. Longi- Proc. Fla. State Hort. Soc. 97: 1984. 244