Department of Horticulture University of Hawaii. In This Issue: FLOWER AND NURSERY INFORMATION No. 57, November Method #3 Side Back

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1 HORTICULTURE DIGEST Department of Horticulture University of Hawaii Cooperative Extension Service U.s. Department of Agriculture Cooperating In This Issue: FLOWER AND NURSERY INFORMATION No. 57, November 1980 TABLE OF CONTENTS Page Rapid Clonal Propagation of the Rainbow Shower Ag College Staff Changes Growth Continues in Hawaii's Ornamental Industry Events...,... 5 New Plantlntroductions Available Publications... 6 Directory of Ornamental Commodity Groups... 6 RAPID CLONAL PROPAGATION OF THE RMNBOWSHOWER The Rainbow Shower (thought to be a hybrid between Cassia fistula and Cassia javanica) is the official City Tree of Honolulu. It sets few seed pods as the F 1 progenies are apparently sterile. Since the introduction of the Rainbow Shower over 50 years ago a number of named clones (e.g. Wilhemina Tenney) have been selected and collections (such as the Cameron collection on Maui) reveal a great assortment of plant growth habits, flower color, and season of flowering. Vegetative methods of propagation have been restricted largely to grafting and air layering as cuttings fail to root (2). Some grafted trees were produced by a Mr. Holt of Makiki Nurseries but the technique has never caught on. In the West Indies chip budding and veneer grafting of the Hawaiian Rainbow Shower onto seedling C. javanica was unsuccessful (I). In fall 1976 a comparison of C. javanica and C. fistula as rootstocks was attempted using 4-year old seedling trees at the Waimanalo Experimental Farm for grafting and I ~ year old containerized seedlings for budding. Three methods of bark grafting were used and three budding techniques (T-bud, inverted-t-bud, and chip-bud) (Figs 1,2) II. Method #1 Method #2 Method #3 Side Back Front Scion used was the same for all three methods. Figure 1. Methods of bark grafting 1

2 J I ~/ lj ql ~ I 'a ~ J I 'I d ~ front view side view T-bud Inverted T Chip bud ll~11 I J Figure 2. Methods of budding Experimental The budding and grafting operations were done in 1976 from mid-october to mid-november. On October 14 and 28, the bark of C. fistula was readily slipping but by November 18 it was no longer slipping. On October 28, the bark of C. javanica was not slipping. The diameters of the field-grown rootstocks ranged from 7 to 12 cm for C. fistula and 7.6 to 9 cm for C. javanica with bark thicknesses up to 2 cm. The rootstocks were cut back to 26 to 130 cm for the bark grafts. Two Rainbow Shower scion pieces, each with three plump buds were grafted onto each C. fistula or C. javanica rootstock. There were 8 attempts of each of the three bark grafting methods made. The scions were placed on the side of the tree from which the prevailing winds came. This was done for added support. After insertion, the scion was nailed in place and tied to the rootstock with nurseryman's tape to ensure secure contact. The scion and entire grafted area and top of the stump were covered with paraffin or Tree Seal wrapped with plastic bags to prevent drying or excess wetting. Rainbow Shower budwood was collected for budding onto C. fistula rootstocks. T-bud, inverted-t-bud, and chip-bud methods were used. Before insertion of the bud, the wood of the bud was removed to facilitate better cambial contact between the bud and the rootstock. The budded area was wrapped in one of three ways: 1) with the bud left uncovered and held in place with nurseryman's tape, 2) with bud completely. covered with tape, or 3) with bud and edges of tape covered with Tree Seal. Results and Disc~ssion Bark grafting successes were on the C. fistula rootstock, but this represented only 20% take. 2 Method 2 gave more successes than Method 1 while there were no takes with Method 3. Successes were possible as late as November 18, even though bark was no longer slipping. The lack of general success may be attributed to I) technique, 2) disease, especially on rootstocks cut close to the ground-yet there were 3 successes on these, 3) lack of bark slippage for C. javanica, and 4) physiological problems related to condensation in the plastic bag coverings. Observation of the bark grafts 4 years later showed that some scions had made good unions while others had taken but later had broken off. The large diameter of the rootstock seemed a little out of proportion to the scion. It is recommended that 3 or 4 scions be placed around a large diameter trunk. If more than one takes, the most vigorous is allowed to dominate and the others are gradually cut back while aiding the healing of the original wound. T -budding of Rainbow Shower on C. fistula.

3 There were no takes for any of the budding methods on C. fistula. The explanations include: 1) technique, 2) condition of the rootstockthick bark, and a non-vigorous state of growth, 3) too tight binding of the bud, and 4) handling of the bud. When the wood is removed from the bud, it should be slipped sideways so as to minimize damage to the vascu,lar bundles to the bud, but in these attempts it was pulled out and may have injured the bud. While T -budding has been used successfully by one of us (R.C.), it was em younger, thinner stock. Chip-budding has been used successfully for a sterile Cassia on C. javanica seedlings in the West Indies (1). It would seem desirable to repeat this work using seedling rootstock in a vigorous stage of growth with a stem diameter of about 1 to 1.5 cm and thin bark. The potential growth of this plant material after planting in the field should equal an air-layered branch or surpass it due to the more vigorous root system. (1) Anon University of the West Indies Department of Crop Science Annual. Report Departmental Paper No.4. Research Summaries, page 3. (2) Ching, P Unpublished master's studies. Janis Eyre, graduate student Richard A. Criley, Professor AG COLLEGE STAFF CHANGES A number of staff changes have occurred in the past several months within the College of Tropical Agriculture and Human Resources (CT AHR) of the University of Hawaii at Manoa which directly or indirectly affect the ornamentals industry. Some of the more significant developments are summarized below. Ruth Y. Iwata Ruth U. Iwata recently joined the college as Assistant Specialist in Ornamental Horticulture, stationed in Hilo. She will provide much needed support for the nursery extension program on the Big Island as well as develop a research program in nursery crop production. Dr. Iwata obtained her Ph.D. from the University of Hawaii with a dissertation on the genetics of flower color of anthuriums and the chemical chara'fterization of anthurium flavonoids. Born in Kona, Dr. Iwata attended Hilo High School. She served in the Navy as a nurse, 3 earning her M.A. at St. John's University in New York. Dr. Iwata worked as a research assistant in the Department of Horticulture for four years before joining the Hilo Agricultural Complex. She is married and has three children. Chien Leng Chia Chien Leng Chia recently joined the College as an Associate Specialist in Horticulture located in the Horticulture Department on the Manoa Campus. Dr. Chia fills the position vacated by the retirement of Warren Yeeand will provide leadership for the extension programs for the State's fruit crops industry. Before joining the University faculty, Dr. Chia worked as a plant breeder and scientist in charge of the research program at the Windsor Shade Tobacco Co., Hartford, Conn., with activities in Massachusetts and Puerto Rico. Dr. Chia earned his Ph.D. in pomology at Cornell University. He also holds an M.S. in Horticulture and a B.S. in Agricultural Technology from the University of Hawaii. Roy K. Nishimoto Roy K. Nishimoto, Professor of Horticulture was recently appointed Chairman of the Horticulture Department at the University of Hawaii at Manoa. Dr. Nishimoto is recognized worldwide for his weed control program on tropical horticultural crops. Dr. Nishimoto is a native of Kauai and holds a Ph.D. degree in Physiology and Herbicides from Purdue University, a M.S. degree in Weed Control and B.S. degree in Farm Crops from Oregon State University. Tadashi Higaki Tadashi Higaki will, assume the overall leadership for the agriculture research and extension programs on the island of Hawaii. Dr. Higaki was recently appointed County Extension Chairman and Branch Station Superintendent. Dr. Higaki is well recognized for his outstanding extension and research contributions to the anthurium industry. He has served as county extension agent, county extension chairman and researcher at the Hawaii Agricultural Experiment Station in Hilo. Noel P. Kefford With the resignation of Furtick, Dr. Noel (Ned) P. Dean William R. Kefford has been

4 named Interim Dean until a pennanent Dean can be selected for the College of Tropical Agriculture and Human Resources. Dr. Kefford will continue to serve in his position as Director of the Hawaii Institute for Tropical Agriculture and Human Resources (HIT AHR). Dr. Kefford is an internationally recognized botanist, who came to Hawaii in 1965 from Australia where he served as principal research scientist in the Commonwealth Scientific and Industrial Research Organization. He served as chainnan of the Department of Botany from when he was named Acting Director ofhitahr. Three Horticulturists Promoted Three members of the Horticulture Depart: ment received promotions at the June Board of Regents meeting in recognition of their contributions to the College. Drs. Richard Cri1ey and Tadashi Higaki were promoted from Associate Professor to Professor and Dr. Fred D. Rauch from Associate Specialist to Horticulture Specialist. Fred W. Fujimoto Fred W. Fujimoto, University of Hawaii Cooperative Service Agent, received the 1980 Distinguished Service A ward from the Hawaii Association of County Agricultural Agents. Mr. Fujimoto was chosen for outstanding achievement as an Extension Agent and for his innovative programs in cooperative marketing and fann business management. He has taught classes on Oahu in crop management, and has assisted in planning and conducting State Commodity Conferences. He is a graduate of the University of Hawaii with a B.S. in poultry and a M.S. in agricultural economics. Mr. Fujimoto has been an Extension Agent for 15 years and served four years as Oahu Extension County Chainnan. GROWTH CONTINUES IN HAWAII'S ORNAMENTAL INDUSTRY Results of the most recent survey of flower and nursery production in Hawaii conducted by the Hawaii Agricultural Reporting Service showed that the wholesale value of these products in 1979 climbed to a record high of $20.8 million. This was a 19 percent increase over the 1978 value and continued the upward trend of recent years (Table 1). The wholesale value of ornamental crops is up \ 431 percent over 1969, which represents an average annual growth rate of 43.1 percent for the 10-year period, Table 1. Wholesale value of flowers. ornamentals and nursery crops produced in Hawaii durinu the 10-year period, ~ Year Wholesale value $ Total Annual ,910, ,225, ,484, ,244, ,674, ,211, ,767, ,828, ,003, ,458, ,778, A breakdown of some major commodities grown in Hawaii also reveal some interesting trends (Table 2-5). Anthurium production continues to lead Hawaii's growing ornamentals industry with a 11.0 percent increase over 1978, climbing to a record $5.6 million wholesale value. This represents an average annual growth rate of 55.7 percent for the 10-year period of Table 2. Wholesale value of anthuriums produced in Hawaii during the to-year period, Year Wholesale value $ Total Annual , , ,032, ,150, ,500, ,720, ,988, ,500, ,372, ,017, ,568, Orchid production during the 1 O-year period, , continued at a modest average annual growth rate of 13.8 percent, reaching a new high of $2.5 million wholesale value. Production of cut dendrobium orchids and potted orchid plants made substantial gains, up 41.2 and 66.1 percent respectively over 1978 in wholesale value. Production of other orchids continues to decline in the State.

5 Table 3. Wholesale value of orchids produced in Hawaii during the 10-year period, Year Wholesale value $ Total Annual ,075, ,107, ,073, , ,178, ,204,000' ,340, l ,438, ,786, ,999, l ,534, Production of other cut flowers and foliages in Hawaii continues to show a steady increase with an average annual growth rate of 23.5 percent. The infantprotea industry continues to show growth, up 27.1 percent over Significant increases were also noted in the production of ginger, pompom chrysanthemums and cut ti leaf, up 50.7, 38.2 and 15.4 percent respectively over Declines were recorded in birdof-paradise, down 25.0 percent, and pikaki, down 12.0 percent ,318, ,467, l ,552, ,854, ,091, ,510, ,685, ,298, ,401, ,958, ,411, l.4 The most rapidly expanding segment of the ornamentals industry in Hawaii, , was the production of nursery plants for landscaping and potted foliage plants for homes and offices with an ~verage annual increase of percent. This represents a wholesale value of $8.3 million for The production of land- 5 scape plants for the local market shows a healthy increase of 26.6 percent after the decline the previous year. This is in addition to the continued increase in production of potted foliage for the export market with a 58.7 percent increase over Table S. Wholesale value of nursery and potted foliage plants produced in Hawaii during the 10-year period, Year Wholesale value $ , , , ,245, ,905, ,730, ,754, ,592, ,444, ,484, ,265,000 Total Annual Fred D. Rauch Horticulture Specialist EVENTS Table 4. Wholesale value of other cut flower PROPAGATION WORKSHOP and foliages produced in Hawaii during the A propagation workshop will be held on 10-year period, November 7, 1980 at the Pacific Beach Hotel in conjunction with the Hawaii Farm Bureau Con- vention. The program, sponsored by HAN and Year Wholesale value S Total Annual local members of the International Plant Propagators Society will start at I :30 p.m. and conclude after a break for dinner. ORNAMENTAL SHORT COURSE The 4th Annual Ornamental Short Course will be held at the Maui Community College, Kahului, Maui on January 15, The program will include concurrent session in the afternoon on nursery crops and protea. Featured speakers will include Dr. Martin F. Stoner, Plant Pathologist from California State Polytechnic University Pomona and Dr. James K. Rathmell, Jr., Floriculture and Nursery Agent, The Pennsylvania State University. Field tours are planned for Friday, January 16. NEW PLANT INTRODUCTIONS Two plants, new to Hawaii, were recently made available to commercial growers of the state by the Horticulture Department of the

6 University of Hawaii through the plant distribu- mation on a series of herbicide trials conducted tion committee of the Hawaii Association of on chrysanthemums and carnations in Hawaii. Nurserymen. The first release was to those Suggestions are provided for trial use of several making requests from the display of potential herbicides on these crops. new plants at the HAN Annual Conference and Trade Show. Additional plants will be propagated and made available upon request. The two new introductions to the nursery trade are: Lonicera japonica ~ tropurpurea' Texas Honeysuckle A vigorous ground cover for full sun; fairly drought resistant when established. This cultivar is similar to the species except that its leaves are tinged with purple underneath and it has purplish-red flowers when they first open. Very popular ground cover plant in Southern California. Ficus stricta Cuttings of this interesting Ficus species, originally from Java, were obtained from a grower in Queensland, Australia who imported it from Europe. It is useful as an indoor foliage plant, responding to growth regulators to give a more compact, bushy growth habit. It may also be cultivated as an outdoor landscape specimen useful as a street tree or shade tree in parks and campuses. It has shown very rapid growth and seems well adapted to Hawaii conditions. AVAILABLE PUBLICATIONS State Laws Affecting Farmers A digest of the acts affecting farmers that were enacted by the Legislature of the State of Hawaii during the 1980 Regular Session is presented in Miscellaneous Publication 179, 1980 State Laws Affecting Farmers in Hawaii. This summary was prepared by Dr. Stephen M. Doue, Extension Economist in Agricultural and Resource Economics. Citrus Rootstocks Reprints are available of an article published in The Plant Propagator by Dr. Robert M. Warner on Rootstocks for Hawaiian Citrus. It discusses the rootstock problems of growing citrus in Hawaii, the production of seedling rootstocks and a discussion of the various rootstocks tested in Hawaii along with comments on those recommended for use with various citrus varieties. Ronstar Trials in Container-Grown Ornamentals Research Report 199 by Nishimoto, Hirano, Rauch and Hibbard on Herbicide Evaluation Studies with Special Emphasis on Oxadiazon 2G in Container-Grown Ornamentals in Hawaii presents the results of a series of experiments conducted on a variety of container-grown ornamental plants to determine the effectiveness and safety of Ronstar and other preemergence herbicides. Of the materials tested, Oxadiazon 2G (Ron star) was most promising for Hawaii Nurseries because of its safety to a wide range of container-grown ornamental plants and its control of the most common weeds now present in nurseries. DIRECTORY OF ORNAMENTAL COMMODITY GROUPS With the large number of changes in the leadership of the various ornamental commodity groups in the State, it is necessary to update the directory periodically. This is being done to provide you with the most current information available. Aloha Arborist Association President: Stephen Nimz 3620 Waialae Avenue Honolulu, HI Anthurium Association of Hawaii, Inc. President: Tracy Lauder P. O. Box 333 Mountainview, HI Anthurium Council of Hawaii President: Mr. Mitsuo Murashige 75 Aupuni Street Big Island Anthurium Growers Association President: Mr. Daniel Hata Kurtistown, HI Mum and Carnation Weed Control Research Report 187 by Nishimoto,. Rauch, Hori and Parvin on Weed Control in Chrysanthemums and Carnations in Hawaii provided infor- 6 Big Island Chapter of HAN President: Mr. Patrick McGrath 44 Anela Street

7 Big Island Dendrobium Growers Association President: Yoshio Watanabe 875 Komohana Street Florist Association of Hawaii President: Ms. Shirley Thompson 2083 Kuhio Avenue Honolulu, HI Garden Island Orchid Society President: Mr. Roland Nitta P. O. Box 194 Kekaha, HI Hawaii Association of Nurserymen President: Mr. Patrick Takahashi P. O. Box 293 Honolulu, HI Hawaii Chapter of the American Society of Landscape Architects President: Mr. Tom Fake 1136 Union Mall #902 Honolulu, HI Hawaii Dendrobium Orchid Growers Association President: Mrs. Helen Wong Mahailua Street Waimanalo, HI Hawaii Landscape Contractors Association President: Mr. Greg Boyer Kamakoi Road Kaneohe, HI Hawaii Protea Cooperative President: Mr. Ed Holroyde P. O. Box 68 Kula, HI Hawaii Turfgrass Association President: Mr. Mark Holley 1690 Ala Puumalu Honolulu, HI Hawaii Yanda Association President: Mr. Haruo Taira Pahoa, HI Hilo Florist & Shipper's Association President: Mr. Richard Iwasaki P. O. Box 5406 Hilo Orchid Society President: Mr. Yoshiharu Tsubaki 255 Aipuni Street Kauai Anthurium Association President: Mr. Gilbert Carvalho P. O. Box 122 Lawai, HI Kauai Association of Nurserymen President: Mr. Lelan Nishek P. O. Box 3013 Lihue, HI Kona Coast Growers Association President: Dr. Melvin Wong P. O. Box 208 Kealakekua,HI Maui Association of Nurserymen President: Mr. Christopher Curtis RRI-Box 675 Haiku, HI Maui Flower Growers Association President: Mr. Craig Rasmussen 357 Ihe Street Kula, HI Oahu Nursery Growers Association President: Mr. Kenneth Y. Ibara P. O. Box 293 Honolulu, HI FOOD FOR THOUGHT "I must do something" will always solve more problems than "something must be done!" The man who can smile when things go wrong has thought of someone that he can blame it on! NOTE: The use of trade names is for the convenience of readers only and does not constitute an endorsement of these products by the University of Hswlll, the CoDege of Tropical Agriculture and Human R.esources, the Hawaii Cooperative Extension Service, and their employees. Extension Specialist in Horticulture 7