August2014Newsletter - Coalition for Orchid Species
Transcription
August2014Newsletter - Coalition for Orchid Species
August 2014 Meets every third Monday of the month The COALITION for ORCHID SPECIES at Fairchild Tropical Botanic Gardens 10901 Old Cutler Road Coral Gables, Florida www.cosspecies.com PRESIDENT’S MESSAGE Dear Members, The dog days of August are here, but soon it will be time for all the orchid action to start. October will see the East Everglades’ show at R.F. Orchids, the South Florida Orchid Society’s show at U of M, and the West Coast Orchid Society’s show in St. Petersburg. But most importantly in October will be our annual Auction. Please be ready to share a division or extra plant so our auction can be a great success. If you want you can bring it into any of the upcoming meetings and we will give it TLC until the auction. November we have a field trip to Henington farms where there is free parking, free refreshments, but the orchids will cost you. John and Karen will be featuring spotted cattleya species and their hybrids Lou August program will be on Tolumnia species (formerly called Equitant Oncidiums). This is a program from the AOS Coalit ion for Orchid Species August Page 2 The 2014 Symposium is now behind us and it is time to acknowledge our volunteers who helped make it a success. Big thanks to the committee in charge of the food service; Lori Sell, Vivian Waddell and Cynthia White. Before she left for California, Melana Davison provided menu suggestions and some practical advice. Lori and Cynthia went shopping and Vivian acted as coordinator. There would not have been any breakfast or lunch without the volunteers who chopped, sliced, arranged and put everything on the table. Thank you very much, Yvonne Bernard, Ovetta Chalmers, Lorraine Lee, Gloria Messler, Mary Foster Munn, Haydee Navas, Guillermo Salazar, Jim & Linda Wheeler and Cynthia White. Sincerely, Vivian Waddell Coalit ion for Orchid Species August Page 3 The Orchid Snail as a Pest of Orchids in Hawaii Robert G. Hollingsworth and Kelvin T. Sewake 1U.S. Pacific Basin Agricultural Research Center, Agricultural Research Service, USDA Department of Plant and Environmental Protection Sciences, CTAHR 1 2 2 ith a little practice and knowledge of pest management, orchids can be grown generally free of serious pests. But in recent years there has been an upsurge in problems caused by a root-feeding pest called the orchid snail or bush snail, Zonitoides arboreus (Say). Description Adult orchid snails are yellow-brown and about an eighth of an inch in diameter. The body of the snail is dark grayish-blue. They damage plants by feeding on the thick, corky roots that grow from the base of the plant (Fig. 1). Ordinarily these roots grow down into the media, holding the plant firmly within the pot. However, plants infested with snails become unstable. They cannot be sold until the pests have been controlled and the roots have re-grown. It only takes two or three adult snails in the medium of a 4-inch pot to cause serious root damage. Pest status In a 1999 survey of commercial orchid growers in Hawaii, 44% of the 64 respondents reported this snail species as a pest in their greenhouses, costing them an average of $503 per year in control costs and $5,708 in lost sales during the previous 12 months (unpublished survey data). Growers reported damage on nine different types of orchids, particularly in the genera Oncidium, Dendrobium, Cattleya, Phalaenopsis, and Vanda. Orchids in the Oncidium alliance were mentioned most frequently as being susceptible to attack (42% of the instances reported). The disparity between the amount of money these growers spent to control the pest and the value of lost sales indicates the insidious nature of the damage. In many cases, by the time the grower discovers the problem, serious damage has already occurred. It is not clear why problems with orchid snails are increasing, because this snail species is not new to Hawaii. According to Dr. Robert Cowie of the Bishop Museum, the orchid snail has been present in Hawaii since at least 1928. In its native range (North America and Central America), this snail is commonly found under the loose, moist bark of decaying trees, or in decaying wood or vegetable matter. Pest interception records kept by quarantine inspectors indicate that potted orchids are the most common commercial host for this snail. Orchid snails have also been reported as a pest of sugarcane roots in Louisiana. The recent increase in snail damage in Hawaii may be related to the rapid growth of the commercial potted orchid industry since 1990. Most potted orchid growers use bark or coir media, which provide a moist environment conducive to snail growth. Previously in Hawaii most orchid growers were cut-flower producers and used cinder or basaltic rock as the growing medium. Some growers have suspected that purchased bark or coir media may be the source of their snail problem. However, we were unable to recover any snails from several types of bark and coir media that we purchased and tested for the presence of snails. Further, we discovered that fresh snail eggs allowed to dry for a week will not hatch, even when rewetted. In addition to the damage they cause, snails are a concern because shipments of potted orchids may be rejected if snails are found by plant quarantine inspectors. Although the orchid snail is widely distributed on the mainland United States and in other parts of the world, this would not necessarily prevent quarantine inspectors on the mainland from taking quarantine action if snails were found. Biology In laboratory and greenhouse studies, we have discovered that orchid snails develop slowly, despite their small size. A snail completes its life cycle in about three months. Adults lay small white eggs (about ⁄25 inch in diameter) in clutches within the pots of orchid plants (Fig. 2). These hatch in about two weeks. No one has measured how long these snails live outdoors or under greenhouse conditions. In the laboratory, orchid snails have lived more than 16 months. Their shells contain calcium, and laboratory-reared snails fed lettuce or cabbage grow faster when given supplemental calcium in the form of crushed oyster shell. 1 Control In general, this snail species is difficult to control with chemicals, and the best method of control is prevention— sanitation and exclusion. Snails usually come into the greenhouse with infested plant material and then spread to other plants. Growers should keep snail-infested plants on separate benches from plants known to be clean (such as those from flasks). The supports of greenhouse benches should be treated to prevent the spread of snails by attaching copper bands or applying molluscicides. Re-potting plants into clean media after bare-rooting them is a timeconsuming but effective method of reducing the pest problem in extreme cases. Commercial pesticides registered for slug and snail control in Hawaii include formulations containing metaldehyde, iron phosphate (Sluggo ), and methiocarb (Mesurol ). Although some growers have recommended dust appli® ® cations of diatomaceous earth, these proved ineffective in our tests. We did not do any greenhouse tests using iron phosphate pellets, but in the laboratory they did not attract or have an effect on snails. Orchid snails are susceptible to products containing metalde- hyde and methiocarb. Regardless of the product used, a single application is unlikely to kill all of the snails. The key is to use repeated applications at regular intervals (every three to four weeks) until all the snails have been killed. Products containing metaldehyde may be more effective if watering is withheld for a while after treatment. This is because metaldehyde products cause slugs and snails to secrete excess mucus, causing their dehydration and death. Growers must decide for themselves what period of time water can safely be withheld without risking injury to the plants. The effectiveness of pesticide applicationscan be determined by removing and searching the planting medium from a number of orchid plants that were known to be infested previously. Place the collected shells in a clean jar with a few drops of water or with a piece of moist paper towel. Living snails will readily emerge from the shell and begin moving about. In our studies, the three products that were most effective against orchid snails were Slug-fest , a liquid concentrate containing 25% metaldehyde, Durham 7.5% metaldehyde granules, and Mesurol , a wettable powder containing 75% methiocarb. Surprisingly, none of the metaldehyde-containing baits we tested actually attracted snails. Those that had some effect did so because snails accidentally contacted the baits. Growers are cautioned that baits containing metaldehyde products are very attractive and highly toxic to dogs, and Mesurol is a potent nerve poison and thus is classified as a restricted-use pesticide. ® ® ® Disclaimer: Mention of a trade or product name does not imply approval or recommendation of the product to the exclusion of others that may also be suitable. The description of a pesticide use is not intended as a substitute for restrictions, precautions, and directions given on the product label. Users of pesticides are responsible for making sure that the intended use is included on the product label and that all label directions are followed. Neither the University of Hawaii, the United States Department of Agriculture, nor the authors shall be liable for any damages resulting from the use of or reliance on the information contained here, or from any omissions to this publication. Coalit ion for Orchid Species August Page 5 August Climate Data Average high: 90.6 Average low: 76.5 Average mean: 83.6 Average rainfall: 8.63" July and August are the two most similar months in South Florida. Most of the advice on watering, disease and pest control in last month's calendar still apply but subtle changes are taking place. Although it may not seem so, as temperatures climb into the low nineties most afternoons, summer is in retreat: each day a little shorter, each night a little longer. With shorter days the importance of watering as early in the morning as possible comes to the fore. With less hours of sunlight to dry the plants, extra care should be taken in choosing when to water. Back to the basics of the classic saying : If a Vanda looks like it needs water, water it; If a Cattleya or Oncidium looks like it needs water, water it tomorrow. If a Paph or a Phal looks like it needs water- you should have watered it yesterday. If plants retain water even from an early morning watering, allowing them to dry a bit harder before the next watering is always a good idea. An extra day of drying rarely does harm. August should provide numerous opportunities to dry each orchid to its desired level of dryness. Take the opportunity to dry your orchids "hard" at least once but preferably twice in August. This will give your orchids a leg up on their mortal enemies, the fungus, before the drizzle of September switches the advantage to our adversaries. August is definitely not the month to over indulge in water. September, the soggiest of months, is next up. The corollary to this calculated drying is the concept that when watering in August above all water thoroughly. If watering is necessary be sure that the roots and medium are totally saturated with the application. The drizzling rains of September are so detrimental precisely because they keep the foliage of the plants wet unduly long. We want our plants which are still growing to receive plenty of water but also plenty of drying time. Good air circulation and proper watering are the keys to disease prevention. Remember that your plants will have increased considerably in size by this point in the growing season. They have added extra growths and extra leaves across the summer. August is a good time to evaluate the spacing of our plants. Remember the old Florida saw that one needs a cat to grow good orchids because when properly spaced a cat should be able to navigate the benches between plants without knocking them over. While we can not recommend specific chemicals, the county agent recommends Banrot, a convenient combination of Thiophanate-methyl and Truban which controls a number of leaf-spotting diseases and soft rots, for home owner use. A combination of Thiophanate- methyl and mancozeb has also been recommended. This can be found pre-packaged as Duosan. If one can over come the aversion to chemicals and can learn the safe application of them, they are valuable tools to better orchid growing. An ounce of prevention is worth a pound of cure especially before the soft, slow drizzle of September sets in. Lengthening nights in August mean cooler nighttime temperatures. Many sympodial orchids are reaching the end of their growing cycle and require less nitrogen. Cattleyas and oncidiums have maturing bulbs. Genera that become deciduous in winter like nobile dendrobiums, calanthes and catasetums should be given much less nitrogen in August to prevent them producing an unwanted off season growth and perhaps forgetting to flower. Substitute an additional application of potassium nitrate and Epsom salt (1TBS each per gal) instead of the balanced 20-20-20. Vandas will respond well to this also, as several of the parental species of our hybrids produce blooms on shortening day lengths and lower levels of nitrogen in their fertilizer seems to egg them on. As explicated in the last chapter, modern research indicates that orchids require less phosphorous than previously thought. This concept should lead us to more judicious use of phosphorus. Fertilizer high in phosphorus may still be of some value at the end of the growing season, perhaps not so much as stimulus as shock. One or two heavy applications in succession, a week or so apart will certainly provide all the phosphorus and all the stimulus(or wake up shock) our plants require to bloom. Snails can be somewhat of a problem in August too, but left to multiply they will be in their full glory when those slow unrelenting rains of September set in. Control them with baits in pellet or liquid/paste form. Remember, these are baits, the pests are drawn to Coalit ion for Orchid Species August Page 6 them. Therefore apply lightly, but frequently. Because they wash away in the heavy rains, baits should be reapplied every two weeks. One pellet every two to three feet will do the job, but one application will not. Given a choice, the smallest pellets baits are best. They keep us from over applying and also pose much less threat to neighborhood pets. A small bait in a Vanda crown is a nuisance , a large bait can be a disaster. If you have been waiting to make cuttings of the terete vandas or reed stem epidendrums, you can wait no longer. The potting season is drawing absolutely to a close. Pot up those overgrown phals before they even think of spiking. Re-set those strap leaf vandas early in August whilst they still have just enough time to re-establish themselves in the September humidity and before the cool weather arrives and their root growth slows or stops. As in all seasons be sure that the plants are firmly set in their containers. There is no "wiggle room" this late in the growing season to restart tender roots that have been chafed off a loosely set plant. As the cooler weather approaches try to give plants that have been repotted late more protection from the first cold snaps. Coalit ion for Orchid Species August Page 7 Coalit ion for Orchid Species August Page 8 Q. Coconut Chips I am having good luck growing my orchids in coconut chips. Should I be using a balanced (with a 1-1-1 ratio) fertilizer or a high-nitrogen fertilizer (3-1-1 ratio) as for fir bark? — J. Jameson A. Coconut products are being used, both as chips and as a ground material that has a consistency like peat moss, as potting media for man genera. In discussions with several growers, notably Terry Root of The Orchid Zone, it seems that coconut-husk products are composed mainly, if not entirely, of lignin, rather than cellulose. Lignin requires many more steps to break down than cellulose, the main constituent of wood and bark products, and so would not appear to be subject to the same wood-rot bacterial action that is the reason higher-nitrogen formulas are required for bark culture. In other words, a balanced formula will be best. Coconut products have the added benefits of being a renewable resource as well as being the last remaining unused portion of the coconut. — Ned Nash Coconut husk chips are usually soaked in several changes of clean water before use. Thank you AOS http://www.aos.org Coalit ion for Orchid Species August Page 9 Coalit ion for Orchid Species August Alan Koch, Bruce Rogers, Ron Kaufman, and Manolo Arias, Page 10 Coalit ion for Orchid Species August Manolo Arias, Bruce Rogers, and Ron Kaufman Page 11 Coalit ion for Orchid Species August Page 12 1.Finish cutting teretes and reed stem epidendrums early in month 2. Reset strap leaf vandas early or not at all 3. Dry hard once or twice 4. Continue anti fungal spray program 5. Apply snail bait lightly twice ten days apart 6. Be sure trees are properly pruned to withstand storms Coalit ion for Orchid Species August Page 13 Remember we are a SPECIES society and we ask you only bring orchid species for our silent auction. If you want to bid on an orchid, please decide how much you are willing to pay, bid that amount and then walk away from the table. We kindly ask that you not hover around the table so others may see the what we are offering. Coalit ion for Orchid Species August Page 14 Coalit ion for Orchid Species August Page 15 Coalition for Orchid Species August Page 16 Get your raffle tickets for a chance to win fabulous orchids from outstanding orchid venders. GOT SPECIES? Get your 2011 COS Newsletters on the web at www.cosspecies.com Special Thanks to Webmasterdesigner Mike Haynes of ISatisfy.com, and Home Page photos by Greg Allikas, www.orchidworks.com! The Florida-Caribbean Regional Judging Center of the American Orchid Society invites you to bring your orchids in flower to be judged by our teams of experienced American Orchid Society Judges, or just come to learn more about orchids and the process of judging orchids. We meet the THIRD Saturday of each month at beautiful Fairchild Tropical Botanic Garden, Corbin Bldg., 10901 Old Cutler Rd., Coral Gables, FL Judging begins promptly at 1:00 p.m. Coalit ion for Orchid Species August Page 17 The first field guide to the orchids of Costa Rica and Panama, this book is lavishly illustrated with 240 stunning color photographs and 229 line drawings. It contains keys to all the orchid genera in the region and most of the orchid species. To enable nonbotanists to identify at least the genus of orchids, Robert L. Dressler emphasizes features that can be readily seen with the naked eye or a hand lens.Written in a friendly and accessible style, this guide begins with succinct descriptions of the geography, climate, and vegetation of Costa Rica and Panama, and includes appropriate comments on the peoples and cultures of the area. A discussion of orchid structure and ecology follows. The identification keys are preceded by instructions for use, and a general key directs the user to the appropriate chapter, where condensed descriptions and additional keys narrow the choices for the plants identity. Dressler avoids complex terminology and supplies a glossary of technical terms that will he helpful to those unfamiliar with botanical vocabulary. A short appendix describes how to prepare orchids for study, and summarizes laws that affect plant collectors, and another lists the authors of species names used in the guide.Reflecting the autor's deep and broad knowledge of the orchids of tropical Latin America, this field guide is certain to prove valuable to botanists, field biologists, orchid hobbyists, and tourists interested in natural history.Robert L. Dressler, a highly respected orchid specialist, is Adjunct Curator of Vascular Plants as the Florida Found on Amazon starting at $76.72 Need to reach over 180 people every month to move your products? See Lori Sell for information about placing an advertisement in the “When two friends understand each other totally, the words are soft and strong like an orchid's perfume” Coalit ion for Orchid Species August Page 18 Please patronize our loyal advertisers! Www.csorchids.com Where Quality is as Traditional as the Orchid Itself 28100 SW 182 Ave. , Homestead, FL 33030 305-245-4570 * rforchids@aol.com *www.rforchids.com For Sale Benches from $65.00 and up (4 to 5 step) For info: call Eddy or Gloria Rodriguez (786) 683-4616 or (786) 7972054 Susana and Victor Ortiz Coalit ion for Orchid Species August Page 19 Remember it is important for you to make sure you check in in order to get credit for attending the meeting. The number of meetings you attend determine when you get to pick your holiday orchid. Coalit ion for Orchid Species August Page 20 Coalition for Orchid Species The 2012-2013 Board: President Lou Lodyga Past President, Mirta Russis Heineman Vice Pres., Michele DiBianchi Treasurer: Odalis Navarro Secretary: Lori Sell Trustees: Carlos Segrera, Erna Maxwell, Katria Whitfield, Cynthia White, Vivian Waddell, Bill Capps, Ketty Bergouignan, Carmen Segrera, Rolando Armenteros, Melana Davison Committees: Vivian Waddel: Membership Guillermo Salazar: Conservation Newsletter Editor : Bill Capps Advertising/Reporter : Lori Sell Raffle: Carmen Segrera Photography: open AOS Rep: Lynn Corson Roster: Melana Davison Webpage Liaison: Rolando Armenterso Cynthia White: Silent Auction Refreshments: Sunshine: Mirta R. Heineman Bert Pressman Scholarship: Dr. Rene Izquierdo Remember we are dedicated to the culture and conservation of species. Please bring only species plants for our silent auction. Coalit ion for Orchid Species William Capps Newsletter Editor August Page 21