This is a December, January newsletter because I have a great job and we are not going to be here long enough to do one for each month. We will resume monthly editions in February.
I worked in a nursery in my younger years and I have great memories. Everytime I go to visit a nursery, all I remember are the nice days at the nursery when it was sunny, I was working outdoors and had very little paper shuffling. Ahh!, the good life! The pasture looks very green over there. Today, I got hit with a good dose of reality with an email from one of my nursery friends in Tennessee. This is what he said, "Ken I have a saying, no matter what you do for a living, eventually you will wish that you were doing something different. I'll tell you what we did on the "other side of the fence" today. I loaded a tractor trailer, 24' gooseneck trailer and a ton truck. The high was 24 degrees with a 8 degree wind chill factor. I was outside for most of the day with the cold job of driving the loader. I didn't plan it this way, it is just the way it happened. I try to look on the positive side. Tomorrow we are supposed to get sleet and freezing rain, but I won't be loading trucks tomorrow." He concluded with "Happy Holidays". I feel much better about my warm office now and the fact that I am taking off 2 weeks for Christmas. I have the same benefits as grandparents. I can visit nurseries and enjoy some of the good stuff but I can walk away when the temperature drops to -10 degrees on Christmas eve. (Knock on wood - if it happens, I had nothing to do with it). I appreciate what you do and I am happy to be a part of the industry from the academic side.
Speaking of academic vs. nursery, I was at McCorkle Nursery in Dearing, Georgia two weeks ago visiting their Center for Applied Research. This is a great industry supported research facility that invites regional participation. I tell everyone that I love to play in other peoples' back yard and do team research. We were setting up some hydrangea research at the Center. To do this, we submit a research proposal and it is reviewed by a nursery/academic board. If approved, we supply the expertise and the Center helps get the plants and monitor the research until we can come and evaluate the results. We later analyze the results and write it up for the industry as well as present it during an industry field day. It is a great arrangement between industry and the universities. It also gave me a chance to sneak into Mike Dirr's plant collection and run for the Alabama border with cuttings in hand. Actually, Mike, like J.C. Raulston, says help yourself but leave a little for others. It is cooperation as it should be in the nursery industry.
While I was there I picked up a research report from last year that I had not seen and thought you would like to see some of the results from the Center. Below are some short summaries of a few of the research papers written for the Center. If you see something you need more information on, please send us an email and we will send you a full copy of the report. If you are close to Augusta, stop by and see the Center. Kay Bowman is the research manager and enjoys visitors. Her nusery is always clean. (706-597-8022 ext. 135)
By the way, have you ever seen a more colorful fall/winter in Alabama? Many people I talk to around central Alabama continue to ooooh and ahh over the last sparkle of a brilliant colorful extravaganza. We were not very hopeful for fall color with the severe drought we had this year but the last minute bright cool days with a little rain was apparently the perfect recipe for screaming red maples, bright sunshine yellow ginkos and even the oaks had some great maroon contrast colors. If I had had a plant stand on the highway with Japanese maples, I could have made a fortune. (There I go again looking over the fence. I will just go home and enjoy my own maples and let you make the money you deserve for your efforts.)
Please take advantage of the Gulf States Trade Show and Seminars in January. (listed below) If you go once, it becomes a tradition and gets better each time. Stop by and see us at our Auburn University Horticulture booth. Thank you for your support of Auburn University throughout the year. We enjoy serving your educational needs and welcome your suggestions anytime. We wish you a special Holiday season.
EDITORIAL NOTE: Due to a very busy November and the two week Auburn University vacation in late December, we have decided to publish just one newsletter for both months, essentially arriving late for December and early for January. We will resume our monthly schedule in February.
DISCLAIMER: Please remember that all information presented is a summary of research and not an endorsement of any product or a recommendation of chemicals. The official labels from the manufacturing companies offer the legal and proper use and handling information for all products.
The following articles are featured in this month's Something to Grow On:
IT ALL CAME TOGETHER AT THE NORTH ALABAMA NURSERY MEETING
EXPERIENCE THE GULF STATES HORTICULTURAL EXPO
WATCH FOR THE PLANT IDENTIFICATION RESOURCE
POWDERY MILDEW CONTROL WITH PREVENTIVE AND CURATIVE FUNGICIDE APPLICATIONS ON Hydrangea macrophylla CV. 'HOBELLA'
SCHEDULING BUTTERFLY-BUSH (Buddleia davidii FRANCH.) FOR SPRING FLOWERING
PROPHYLACTIC USE OF MICROBIAL CONTROL AGENTS TO PREVENT COLONIZATION OF NURSERY PLANT CONTAINERS BY RED IMPORTED FIRE ANTS, Solenopsis invicta
PRELIMINARY INFORMATION ON THE COLD HARDINESS OF Loropetalum
HYDRANGEA pH AND FLOWER COLOR INFLUENCED BY LIME SOURCES
THE BENEFITS/COSTS OF GRADING LINERS BEFORE PRODUCTION
POINSETTIA PREFERENCES: NEW CULTIVAR EVALUATIONS INDICATE PUBLIC'S FAVORITES
THE SEARCH FOR SALT-TOLERANT TREES
PLANT PATHOLOGY REPORT
IT ALL CAME TOGETHER AT
THE NORTH ALABAMA NURSERY MEETING
Dr. Ken Tilt
Associations succeed when everyone works hard individually and together. What does that have to do with the North Alabama Nursery Meeting? We had a very successful meeting at S&S Nursery and the Huntsville Botanical Garden because all the ingredients of an active association came together to make a particularly memorable event.
Through years of trial and error, we have learned many of the keys to success for developing a good educational program. Working together is the major underlying theme to success. This is appropriate timing for this article: during this Holiday season when we are getting ready to share with family and friends and make resolutions for the next "Bigger and Better" year.
For many years, the Alabama Nurserymen's Association and the Alabama Cooperative Extension System have worked together to provide educational opportunities for the members of ANA. We often included some of the factors that guarantee a successful program but rarely put all of these factors together at one time. We have had good programs but not always great programs.
To run a successful program, you need:
The most important ingredient for any program and any association's success is the last item on the list. Some additional ingredients for success are affordable registration prices, take-home reference material, the incentive of pesticide applicators' points for attending, and great food, drink and promise of a crowd to see old friends and make new contacts. Weather is an obviously uncontrollable factor. A pretty day during a busy time of the year can be disastrous for an educational program. The old saying "make hay while the sun is shining" applies here.
- good, timely material
- knowledgeable, interesting speakers (combination of industry and academic) to present the material
- good timing for the event
- a good location
- industry and leadership support
- members' input and organizational efforts
- members' involvement and ownership in the event
The International Plant Propagators Society (IPPS) has for many years been an association that has "Worked". One of the reasons for success of their meetings, aside from members' involvement, has been having part of the meeting at other peoples' nurseries or greenhouses. These nurseries were willing to share their successes and failures. We had a good meeting last year at MidWestern Nursery in Centre, Alabama. It is always nice to see, touch, feel, smell or hear an aphid, phytophthora root rot, a tree digger, sprayer, mist system, a new camellia or other nursery production applications in a hands-on environment rather than through slides or lectures.
David Bradford, your current ANA president, made a priority and a commitment to energize committees to purposeful action during his tenure as president. Members of the educational committee came from all over the state to meet at the Association office in Auburn to plan this year's educational programs. Vickie Nelson, another board member, and Dr. Raymond Kessler, Extension Horticulturist, had already had good success at regional on-farm, industry sponsored meetings at greenhouse businesses across the state the previous year.
An important avenue for developing successful programs is to adopt and adapt, steal, copy (whatever it takes) others' successes. Nick Strain, an educational committee member, volunteered to host a regional meeting at his family nursery, S&S Nursery, in Athens and Tom, his brother, volunteered to offer his noted culinary talents as the Master Barbecue Chef. Hugh Strain, who is gradually giving up management responsibility of the three generation nursery to the up-and-comers, gave his blessings to the event and gave the order to begin cleaning house in preparation for company. Harvey Cotton, director of the Huntsville Botanical Gardens and board member of ANA, offered the Gardens as a place for the morning educational seminars. A beautiful location, a chance to see what the Strains were hiding in their closets and entertainment by Tom Strain orchestrating the cooking of prime meats in two huge, billowing grills was enticement enough for a successful meeting.
The educational committee decided what topics needed to be addressed and Linda VanDyke and Auburn University and the Alabama Cooperative Extension System located the appropriate speakers. Topics included, weed control and sprayer set up and calibration for effective use of chemicals, fertility management, and an overview of effective nursery systems. The program was approved for certification points by the Alabama Department of Agriculture, Division of Plant Industries. Time was planned to do a quick tour of the Botanical Gardens to demonstrate the partnership and commitment they have with our industry.
The Strains and Doug Chapman, county agent in Limestone County, used their relationships with allied industries to bring in vendors to demonstrate their equipment at the nursery. Vendors love events like this because it gathers many of their customers (or potential customers) in one place thereby maximizing their time and efforts. They came willingly with offers to support any of the events and offer door prizes to the attendees. They rolled their sleeves up and helped set-up and organize. ANA Board members came from across the state to support and help with the program. ALFA volunteered money to help with any of the expenses. A very affordable registration fee was set at $5, thanks to the support from our vendors, ALFA and S&S Nursery. The time was not too busy for the participants and benefits of attending made the program very attractive.
We had about 125 people who enjoyed the 1 day event. Participants were offered educational opportunities and tours through a nursery that has been successful for over 3 generations. We were able to talk to and ask questions of all the employees to see what worked and what needed improving. Vendors were able to demonstrate their equipment in a nursery setting. All the factors came together to make "Painless Education". We enjoyed the food, atmosphere and people so much that we did not realize how much we had learned until we got home and began thinking about the ideas we picked up during the day.
The main focus of this article was the factors that came together to make a great nursery program in North Alabama. More importantly, though, it reveals the secrets of a successful organization. This recent program, the Alabama Nurserymen's Association, and most other things in life work best when we think beyond the entrance to our nurseries and give of ourselves to help others and become involved in our association and industry. These "secrets" to success are not new and have not been hidden. It is just hard to get all the variables assembled and working together. When that happens, it is something special like the recent North Alabama Nursery Meeting.
Let's make it a resolution to make it happen more often next year. Ask how you can be involved in ANA or better yet, go to the meetings, visit the office in Auburn and see for yourself what opportunities are available and dive in. One of the greatest things that can happen to an officer in an organization is to have the membership so active that they have to get out of the way to avoid hindering progress.
EXPERIENCE THE GULF STATES HORTICULTURAL EXPO
For registration information email: email@example.com or for voicemail: 333-502-7777. Pre-registration must be received by January 10).
Make plans now to attend the
3rd Annual Gulf States Horticultural Expo on January 25-27, 2001 at the Arthur R. Outlaw Convention Center in Mobile, Alabama
Educational Opportunities will be held on January 25th ...
... followed by a 600 Booth Trade Show on January 26th and 27th.
"The premier Winter Trade Show of the South"
Wednesday, January 24, 2001 6:00 AM - 4:00 PM Exhibitor Move-In & Set-Up 9:00 AM - 4:00 PM Registration Open Thursday, January 25, 2001 6:00 AM - 5:00 PM Exhibitor Move-In & Set-Up 6:30 AM - 5:00 PM Registration Open 7:30 AM - 3:00 PM 12th Annual ANA Golf Classic - Timber Creek Golf Club 7:30 AM - 12:00 noon Educational Keynote Speakers SEE BELOW 10:00 AM - 4:30 PM Sporting Clays Tournament - Mobile Shooting Center 1:00 PM - 5:00 PM Concurrent Educational Seminars SEE BELOW 6:30 PM - 8:30 PM
Welcome Reception, Gulf Coast Exploreum
Sponsored by: Flowerwood Nursery, Inc., Martin's Nursery, Inc., Tom Dodd Nurseries, Twin Oaks Nursery and Supplies, Inc., Lerio a division of NSI. Friday, January 26, 2001
7:30 AM - 8:45 AM Room 203B Alabama Nurserymen's Association Annual Meeting & Awards Ceremony
7:30 AM - 8:45 AM Room 203A Louisiana Nursery & Landscape Association Annual Membership Meeting
7:30 AM - 8:45 AM Room 204B Mississippi Nursery & Landscape Association Annual Membership Meeting 7:00 AM - 4:30 PM Registration Open 9:00 AM - 5:00 PM Trade Show Open 9:00 AM - 4:00 PM Ladies Program - "Day Along the Bay" (Ticket is Required)
10:00 AM - 12:00 noon Room 204A Alabama Certified Nursery Professional Exam 5:00 PM Trade Show Closes
5:30 PM - 7:00 PM Room 204A Mississippi Nursery & Landscape Association Reception & Awards Presentation 5:30 PM - 7:00 PM ANA Past Presidents Reception/Henry Orr Fund for Horticultural Excellence Campaign Kick-off (Light hors d'oeuvres and cash bar) Saturday, January 27, 2001 7:30 AM - 2:30 PM Registration Open
8:00 AM - 9:00 AM Room 204B ANLA Town Meeting 9:00 AM - 3:00 PM Trade Show Open 10:00 AM - 2:00 PM Outdoor Equipment Demonstration (Weather Permitting) 3:00 PM Trade Show Closes
The educational sessions on Thursday cover the entire gamut of the horticulture industry. Below are workshop and session information. You will surely find subjects that will interest you and potentially help with the bottom line if you are a business owner.
The Role of Plants in a Changing World of Landscape Design
Neil Odenwald, Louisiana
As landscape design has changed over the years, so has the use and selection of plant material. What role do plants play today in landscape design? How does it vary from what we have been accustomed to?
Thinking Outside the Box
Dr. Lawrence Helms, Oregon
This seminar is 100% practical and relates directly to one's professional and personal life. It examines the five major mental locks that need to be opened for more creative problem solving and decision-making. Each lock is examined carefully and procedures are shown that can be used to eliminate that lock as a stumbling block.
The Tropical Revolution
Greg Grant, Texas
S'Merchandising (Smart Merchandising!)
RETAIL/PLANT MATERIAL WORKSHOP
Dr. Lawrence Helms, Oregon
Merchandising is more than clean floors, wide aisles and a pleasant decor. This seminar presents hundreds of totally practical and immediately useable tips in concise easy-to-understand and ready to use form.
The Cottage Garden Concept
Greg Grant, Texas
sMARKETing in the Green Industry
Dr. Lawrence Helms, Oregon
100 different practical and successful ways to market a Green Industry Business.
Exciting Plants for the Gulf States
Norman Winter, Mississippi
No time since the great plant explorations of the late 1700's have we had so many great new herbaceous plants. Plants are pouring in from South America and other regions and they love our climate.
Extending the Shelf Life of Bedding Plants
GREENHOUSE GROWER WORKSHOP
David Tatum, Mississippi
This talk will address the research and new tools to keep bedding plants looking "great" at the retail store.
Useful Performance and Financial Indicators
Dr. Forrest Stegelin, Georgia
Yes, you can grow quality plants, but how are you really doing? How does your business compare with similar firms in size and activities? Is employee performance costing you money? How much money do other nursery and greenhouse operations make on every dollar of sales? Tools and techniques for analyzing the financial performance and other measuring sticks of performance will be discussed so grower/managers can make side-by-side comparisons of their business to other industry participants.
The Nuts and Bolts of Greenhouse Equipment
This presentation will cover how to make the right greenhouse equipment selection.
Greenhouse Sanitation and Pest Exclusion
Dr. Raymond Kessler, Alabama
Greenhouse management practices for excluding insect and disease pests and sanitation procedures to eliminate and prevent pest problems.
LANDSCAPE IRRIGATION WORKSHOP
Landscape Irrigation: Design Concepts and Troubleshooting
Dr. Jim Baier, Alabama
LANDSCAPE NIGHTLIGHTING WORKSHOP
Landscape Lighting for Beginners
Bret Korcykoski, Ohio
A basic overview of landscape lighting techniques, design and layout. Also some basic technical information about light bulbs, transformers and voltage drop.
WOODY ORNAMENTAL GROWER WORKSHOP
BMP's for Irrigation and Fertilization Management - A Research Overview
Dr. Ed Bush, Louisiana
A research overview of irrigation and fertilizer practices in a nursery setting.
Pot-in-Pot Production Robert Trawick, Louisiana
Production recommendations on set up, initial cost and benefits of pot-in-pot production. Dealing with problems associated with pot-in-pot production and what research is leading us to do about these problems.
Ornamental Trails at Mississippi State University
Dr. Patricia Knight, Mississippi
An overview of both woody and herbaceous trials at South Mississippi Branch Experiment Station (USDA hardiness 8).
Woody Ornamental Plants to Produce and Production Recommendations
Dr. Allen Owings, Louisiana
Production recommendations for some of the commonly grown woody ornamental trees and shrubs. New cultivars and species recommended for production will also be discussed.
PEST MANAGEMENT WORKSHOP
Pesticide Update and New Insecticides for the Greenhouse
Dr. Wheeler Foshee, Alabama
Laws, regulations and pesticide safety along with new insecticide products for greenhouse managers.
IPM on Ornamentals
Dr. Dale K. Pollet, Louisiana
Pest infesting woody ornamentals in nursery, urban and commercial settings.
Bedding Plant Disease and Performance Observations
Dr. Allen Owings, Louisiana
An overview of disease observations in 1999-2000 bedding plants landscape trials at the LSU Ag Center. Will include landscape performance of newer cultivars.
Insect Identification and Control - How to Save $$$$$
Brian T. McCaffrey, Florida
A review of the major greenhouse and nursery pests, identify them and show the importance of proper rotation and IPM.
($85 fee for this class)
IRRIGATION ASSOCIATION WORKSHOP
This course covers the fundamentals of pumps. You will learn types of pumps available, which to use for different applications, understanding the relationship between impeller and motor size, reading pump curves and sizing pumps for peak efficiency. You will become familiar with pump controls and their application. In addition, the class will cover wells and pumping systems used with wells. This class is suitable for both landscape and agricultural application.
January is the target date for uploading the Plant Identification Resource, the end product of the funding for an Extension project that will aid Auburn University students in their plant identification classes. The resource will also be of interest to nursery workers and the public at large as you will be able to click on a common name or a botanical name to find photos of leaves, bark, flowers and other identifying traits. Since the delivery of information is on the web we will be able to continually add photos so that eventually it will be an encyclopedic source of plant information for our growing zone. As soon as we have uploaded the site we will publish the URL so you can take a look.
Fungicide treatments used in the study were:
- Phyton 27
- Triact 70
None of the fungicides tested adequately controlled powdery mildew on hydrangea when applied curatively after disease severity was high. The best powdery mildew control was achieved when the fungicides Heritage, Systhane, or Phyton 27 were applied preventively prior to powdery mildew disease development. A benefit of Heritage and to some extent Systhane application was that the spray interval was approximately 14 days for these fungicides, whereas Phyton 27 was applied every 7 days. It was disappointing to find that the biorational, disinfectant, and biological control product of Triact 70 (neem), Timsen, and AQ-10, respectively, were ineffective in controlling powdery mildew even when applied preventively. The best control of Cercospora leaf spot on hydrangea was achieved using the fungicide Systhane, with less than 10% of the leaf area affected by the disease.
Cultivars of Buddleia davidii Franch. and B. weyeriana are popular summer flowering woody ornamentals prized for their ease of cultivation, attractiveness to butterflies and season-long flowering. However, spring sales are inhibited since flowering does not occur until summer. This study was initiated to determine if photoperiod or stage of development influences floral initiation. If so, these factors may be manipulated to force spring flowering of butterfly-bush.
Based on this study, day length appears to have little influence on flower development. Temperature manipulation will probably be necessary to produce flowering plants for the early spring market. Further studies could illuminate minimum growing temperatures necessary to meet these requirements as well as the possibility of using growth regulating hormones to control flowering in butterfly-bush.
Fire ants, Solenopsis spp., colonize soil and potting media in plant containers in nurseries. This creates safety concerns for nursery personnel and provides a means of disseminating fire ants to areas outside of the quarantine program. The objectives of this study were to determine the feasibility of using biological agents to prevent colonization of containerized plants by fire ants and to compare their effectiveness with a standard insecticide used by the nursery industry.
Mixing Talstar with potting media effectively eliminated invading fire ant colonies from containerized plants. The commercially-formulated biological control agents were not effective in eliminating and preventing these infestations. We did observe dead workers and queens on the soil surfaces of containers treated with the biological agents; however, the impact was not sufficient to efficaciously eliminate or prevent infestations.
Five taxa of Loropetalum chinense, including the species, 'Sizzling Pink', 'Ruby' and 'Zuzhovia', were evaluated for cold hardiness monthly from December 1998 through April 1999.
In general, the species hardened earlier than the other cultivars. 'Zuzhovia' was the slowest to reach its maximum cold hardiness level (February) and along with 'Ruby' lost the most cold hardiness between February and March. Plants that gain cold hardiness early in the winter may avoid damage to early frosts and conversely those that lose cold hardiness early in the spring may be susceptible to late spring frost damage. Please note this information is preliminary and that differences may occur in hardiness levels of plants depending on the year, location, or cultural practices used for production.
Dolomitic lime sources and application methods were examined on Hydrangea macrophylla 'Charm Red'. The flower color changes and potting mix pH were recorded to determine the changes. The pink to red flowering hydrangeas require an elevated pH (above 5.5) to produce their red color.
One gallon Charm Red Hydrangeas were potted into three gallons in fall and the pine bark/sand potting mix was amended with 10# and 14#/yd3 of dolomitic lime. Plants overwintered in an unheated poly house were moved to a shade house in spring. The irrigation water has low levels of calcium and the pH is 6.5. Additional lime treatments were applied on March 26 to the pots amended with 10#/yd3 lime. The treatments were (1) 80 grams pelletized dolomitic lime top dressed, (2) 80 grams flowable dolomitic lime drench, and (3) 160 grams flowable dolomitic lime drench. The plants were just beginning to show visible flower buds.
The pH's of the 10#/yd3 and the 80 grams pelletized lime treatments were not statistically different. The flower colors were purple and grape, respectively. The 14#/yd3 fall incorporated treatment had a higher pH (5.7) and pinkish red flowers. The two flowable lime treatments produced even higher pH's (6.2 for the 80 grams and 6.4 for the 160 grams) and strong pinkish red flowers.
The 10#/yd3 dolomitic lime did not maintain an acceptable high pH from fall until spring to produce the desired red hydrangea flowers. The 14#/yd3 treatment, the 80 grams and 160 grams flowable treatments elevated the pH and produced red blooms. The flowable lime treatments worked very quickly to raise the pH and could be used as a spring drench on red flowering cultivars to insure pink to red flowers. These flowable lime rates require a very heavy drench application. It might be more efficient to apply multiple applications at lower rates.
As liners, seedlings, or transplants are potted (or repotted) by a nursery for container production, the plants are often of a mixed "quality" or grade upon arrival. Employees typically pot the liners into gallon containers, for instance, regardless of condition - including the "dead on arrival" - on a piece-rate pay basis for the larger container nurseries. Because of the block potting, no differentiation of plants occurs until marketing, at which time an average price for the container plants is used. This disregards any quality differentials that either may have developed during the growing and finishing time frames or were recognizable upon arrival at the potting shed which would have encouraged differential pricing strategies. Is there any revenue (and/or profit) enhancement from grading liners prior to production and subsequent marketing?
Juniper liners from six flats were sorted by size and condition into four categories: large, medium, small, and dead/empty cells. Of those liners potted, 30.0% were classified as large, 51.4% as medium, and 18.6% as small. Upon potting in March 1999, the containers were set in pot-to-pot formation for growing, maintaining the large-medium-small identity established by the initial grading.
The liners were re-evaluated in December 1999. Size measurements (height and breadth) were obtained for a sample of 20 plants from each of the three size categories (large, medium, and small). For the 20 plants in each size category, the average growth score and the average g.a.p. score was tabulated. The medium-size and the small-size plants had become less differentiated while the large-size plants had discernibly higher average growth scores.
Regardless of the wholesale nursery capacity, initial screening or grading of liners, seedling or transplants to eliminate the possibility of coddling or maintaining non-productive and unmarketable plants reaps monetary rewards in cost savings for labor, equipment, materials, space and time.
Poinsettias are more than traditional floral decorations for the holiday season. They are big business in the floricultural industry nationwide and also in Alabama. In the fall of 1999, 59 poinsettia cultivars were grown at the OHRS to determine their suitability for production in Gulf Coast greenhouses. Rooted cuttings of these 59 cultivars were donated to the OHRS in the summer of 1999 by Paul Ecke Ranch and Fischer USA, Inc.
On November 30, 1999, the Mobile Botanical Garden sponsored a public exhibition displaying representative plants of 53 of the 59 tested cultivars. The public was asked to select their favorite cultivars. The three most selected cultivars were Winter Rose, Carousel, and Holly Point. The most selected red cultivars were Galaxy, Sonora Dark Red, and Supjibi.
Results of this study indicate that the development of new cultivars is expanding the choices of both consumers and growers alike. Many of these cultivars appear to be well suited for production in Gulf Coast growing conditions, and new, unique poinsettias are attracting the attention of consumers looking for new options in their floral holiday decorating.
Salt spray blowing in from the the ocean deforms or kills landscape trees planted at sea side resorts. Salt can damage trees in two ways. Salt within the soil can adversely affect soil structure and damage a tree's roots, causing the crown to thin; however, aerial deposition of salt on the above-ground parts of a plant causes the most damage. Ocean spray is the primary culprit. It is essential that species selected for landscape planting in areas exposed to the gulf or ocean be able to survive and remain attractive in such environments.
The city of Virginia Beach, Virginia, along the Atlantic coast, has struggled with this problem for years. Trees are part of their overall landscape plan but they spend thousands of dollars a year replacing trees that have been damaged by salt. The results of a study by Bonnie Appleton and Susan C. French of Virginia Tech, and Roger R. Huff of the City of Virginia Beach was published in the Journal of Arboriculture, Volume 25, Number 4, July 1999. The name of the article is "Evaluating Trees for Saltwater Spray Tolerance for Oceanfront Sites."
In an effort to identify tree species that could withstand salt deposition without being deformed, a group of allegedly salt-resistant trees was tested in the tree pits along the main thoroughfare of Virginia Beach. Following are the tree species used in the study: loquat (Eriobotrya japonica), goldenraintree (Koelreuteria paniculata), fruitless sweetgum (Liquidambar styraciflua 'Rotundiloba'), lacebark elm (Ulmus parvifolia 'King's Choice'), dwarf southern magnolia (Magnolia grandiflora 'Little Gem'), thornless honeylocust (Gleditsia triacanthos var. inermis 'Shademaster'), and sweetbay magnolia (Magnolia virginiana). None of the species tested in this study is sufficiently resistant to salt-spray damage to be recommended for planting in the harsh environment. Cultural treatments to prevent or reduce salt deposition on trees have proved to be ineffective. Washing off salt deposits after storms was tried and deemed to be impractical, and frequent replanting is economically prohibitive. The authors recommended that tree planting where wind exposure is moderate to high be adbandoned in favor of shrubs, ground cover, and annuals that have proven to be salt tolerant.
Extension Plant Pathology Specialist-Birmingham
Auburn Plant Disease Report-November (J. Mullen)
We were glad to see the rain in November, but do wish it had come just a little earlier. Considering the time of year and the drought problems of last spring-summer-fall, I'm surprised to report 38 samples arriving in the clinic last month. As you might expect, many of the problems were due to environment stresses. Some of the samples were referred on to Entomology. Some were disease.
The landscape azalea with Phytophthora root rot probably had active disease earlier in the season. Roots were decayed as they may become after a variety of problems. ELISA and culture work indicated Phytophthora presence. The fact sheet ANR-571, Phytophthora Root Rot on Woody Ornamentals, describes Phytophthora root disease in a nursery. Control measures differ in a landscape setting. Sanitation of dying plants is still recommended, but application of protective fungicide drenches is usually not economically practical unless a large number of plants need protective treatments. See the Alabama Pest Management Handbook for current fungicide recommendations. When fungicides are not practical, care should be taken that the area has good water drainage and that irrigation is appropriate for the situation. When removing diseased plants, removing root-associated soil is a good idea. Phytophthora root disease development is dependent upon wet soil conditions for a prolonged period of time.
Brown patch was a problem on centipede, St. Augustine, and zoysia. The moderate temperatures and moisture levels of November were conducive for development of this disease. See ANR-492 for details of this disease and control recommendations. See the Alabama Pest Management Handbook (ANR-500B) for current fungicide recommendations. Fungicides should be applied in the fall until grass dormancy occurs.
Pythium crown and root rot and Phytophthora crown rot were seen on pansy samples from landscape and nursery settings. These diseases are frequent problems of pansy. See ANR-500B for current protective fungicide recommendations. Damaged plants should be removed from the area. In landscapes, it is usually more practical to remove soil associated with damaged plant roots and control water problems than to apply protective fungicide drenches.
The Rhizoctonia crown rot on pansy was not visually distinct from the Pythium/Phytophthora problems. Diagnosis of Rhizoctonia was made on the basis of microscopic evidence. Again, in a landscape situation, it is most practical to remove damaged plants and soil associated with these roots.
The palm nursery sample showed a decay of the bud tissues, and ELISA results indicated a Phytophthora and Pythium bud rot. This is not a common problem in Alabama, and I am not aware of fungicides labelled for protective control of this disease on palm. Sanitation of infected buds and near-by tissues would be an important aspect of disease control. Also, overhead watering should be avoided, if possible.
Annual periwinkle was received from a greenhouse situation. Most of the leaves were covered with tiny black spots with spotting concentrated around leaf margins. Some of the spots appeared to be slightly raised. Microscopy and culture work did not produce any disease agents. Considering the widespread incidence and uniform development of this damage on the crop, I suspect an environmental problem may exist. Possibly this damage is a form of edema.
The Phomopsis canker on tulip poplar (Liriodendron tulipifera) appeared as branch cankers. Lesions were sunken and slightly elongated. Tissues under the sunken bark were brown. Culture work produced Phomopsis. This fungus has not been previously reported on tulip tree according to our lab references, but I have not done a library search for more recent reports. Phomopsis is a fairly common canker pathogen on several woody plants. It is often associated with stress situations. As with most cankers, the best control is removal of lesions making sure to disinfest the shears between cuts and making cuts 3-5 inches beyond the edge of symptomatic decay.
Rose samples were submitted with the common rose diseases of black spot, crown gall, and virus mosaic. See ANR-401, Rose Diseases and Insect Control, for details of these diseases and recommended control measures. John Olive, Superintendent at the Mobile Ornamental Horticulture Substation, reported seeing Botrytis on various greenhouse-grown plants including poinsettias. He noted that cooler temperatures are conducive for development of this disease. Another problem observed was very small bracts (less than a quarter of normal size) on poinsettia due to a late application of a plant growth regulator (PGR). This application may have been a slightly high rate as well as being applied late in the growing cycle.
|Azalea||Phytophthora Root Rot||DeKalb|
|Centipede||Brown Patch (Rhizoctonia)||Montgomery, Walker|
|Palm||Phytophthora/Pythium Bud Rot||*|
|Pansy||Phytophthora Crown Rot||Etowah *|
|Pansy||Pythium Crown Rot||*|
|Pansy||Pythium Root Rot||Lee|
|Pansy||Rhizoctonia Crown Rot||Lee|
|Periwinkle, Annual||Edema Suspect||*|
|Rose||Black Spot (Diplocarpon)||Montgomery|
|Rose||Crown Gall-Suspect (Agrobacterium tumefaciens)||Escambia|
|Snapdragons||Pythium Root Rot||*|
|Tulip Poplar||Phomopsis Canker||Colbert|
|Zoysia||Brown Patch (Rhizoctonia)||Baldwin|
The number of samples received in November decreased significantly due to the normal seasonal slow down. Abundant rainfall (8.14 inches at the Birmingham Airport) occurred during November, ending the outdoor watering ban in parts of Jefferson County. This was a welcome relief for homeowners as well as greenhouse growers, nursery owners and other members of the green industry. However, the damage from the drought has been both to the long-term health of many landscape plants and financial health of some members of the green industry.
Brown patch became quite active with the rainfall and overcast conditions last month. The disease was confirmed on samples of centipedegrass and St. Augustinegrass from area lawns. Brown patch is most common during the spring and fall on warm season turfgrass (centipedegrass, St. Augustinegrass, zoysiagrass). Where this disease is a yearly problem on high-quality turf, preventative fungicide applications in fall are superior to curative applications in fall and/or spring. Refer to fact sheet ANR-492 for a complete discussion of the disease. Several pansy samples were submitted to the lab from both greenhouses and landscapes. Black root rot was seen on one sample, and the other samples were related to nutritional problems. Black root rot is difficult to control/cure and severely infected plants should be removed and replaced. See Plant Disease Note - ANR-1052 for a description of the disease and control measures. As a reminder, it's important to use high nitrate fertilizers (>50-75%) rather than high ammonia/urea-based products in pansy beds during fertilization during late fall and winter. Pansies are susceptible to ammoniacal-nitrogen toxicity during cool-wet weather resulting in poor growth. Other disease and insect pests submitted in November are listed in the following table.
|Cherry Laurel 'Otto luken'||Botryosphaeria Canker||Jefferson|
|Cypress, Leyland||Botryosphaeria Canker||Jefferson|
|Pansy||Black Root Rot||Jefferson|
|St. Augustinegrass||Brown Patch||Jefferson(2)|
December is usually our month of least plant samples and most paper work catch-up as well as lab inventories and re-organization. Greenhouse plant diseases develops every month of the year!
The list below includes some common disease problems received in the lab during December of the past few years. Comments on control practices are brief. Refer to the Alabama Pest Management Handbook for details. Also, remember that sanitation is important in most control situations.
|Azalea||Cercospora Leaf Spot (Stress Related)||Brown, circular-irregular spots (¼-½ inch, 0.6-1.2 cm diam.) on yellowed or otherwise weakened/ stressed plants.||Remove stress factors; sanitation.|
|Azalea||Powdery Mildew (Microsphaera) (Greenhouse location)||White, buff-colored dusty coating on leaves.||Apply a protective fungicide (See the Ala. Pest Management Handbook.); Sanitation.|
|Bedding Plants||Bacterial Leaf Spot (Greenhouse location)||Wet, water-soaked/ black spots become dried and cracked in the centers with water-soaked margins.||Sanitation; reduce humidity; increase spacing between plants; See AL. Pest Management Handbook.|
|Bedding Plants||Pythium Root Rot (Greenhouse location)||Roots become brown and water-soaked.||Sanitation; See handbook; reduce irrigation schedule.|
|Bentgrass||Brown Patch||Brown blotches on foliage; blight.||See AL. Pest Management Handbook.|
|Bentgrass||Pythium Blight/Root Rot||Plants yellow and die from root rot phase of the disease.||See AL. Pest Management Handbook.|
|Boxwood||Macrophoma Blight||Foliage turns reddish, yellow or brown with small black dots (about 1 mm diam.) scattered across leaf surfaces.||Remove stress situation; sanitation.|
|Dianthus||Anthracnose (Colletotrichum)||Reddish brown irregular spots on foliage.||Sanitation. Cleary's 3336 may help.|
|Dianthus||Rhizoctonia Shoot Blight||Brown elongated lesions.||Sanitation. See AL. Pest Management Handbook.|
|Dianthus||Oedema||Small, corky, slightly raised spots on lower leaf surfaces some-times accompanied by yellowish spots on corresponding upper leaf surfaces.||Reduce watering on cloudy days.|
|Fern, Boston||Rhizoctonia Aerial Blight||Blight areas on fronds.||See AL. Pest Management Handbook.|
|Geranium||Botrytis Blight||Spots and blight may develop on leaves, flowers, stems. When humidity is high, a gray mold will develop.||Sanitation; increase temperatures; increase air circulation to decrease humidity; protective fungicides.|
|Geranium||Phytophthora Stem Rot||Lower stem areas become black and water-soaked.||Sanitation; See AL Pest Management Handbook.|
|Holly||Phytophthora Root Rot||Roots, especially feeder roots, show a wet, water-soaked, rotted condition where the outer layer easily slips off the central cylinder.||Sanitation; See the AL. Pest Management Handbook.|
|Juniper||Phytophthora Root Rot||Roots, especially feeder roots, show a wet, water-soaked, rotted condition where the outer layer slips off the central cylinder.||Sanitation; See the AL. Pest Management Handbook.|
|Leyland Cypress||Seiridium Canker||Slightly sunken, elongated lesions develop on branches and/or trunk. Resin often oozes out onto bark at points along lesion edge. Tissues beneath bark are brown.||Cankered areas should be pruned out, making cuts 3-5 inches beyond the lesion edge. Disinfest shears.|
|Ligustrum||Cercospora Leaf Spot||Large, brown circular, oval or sometimes angular leaf spots. Sometimes spots have dark brown borders.||Sanitation; protective sprays of Cleary's 3336 or Domain.|
|Mondograss||Anthracnose (Colletotrichum)||Brown blotches on leaf blades; blotches may begin at leaf tips or they may be centrally located on the leaf blade.||Cleary's 3336 or Domain; Protective sprays; Sanitation.|
|Oak||Botryosphaeria Canker||Sunken, elongated lesions develop on branches and/or trunks. The lesion edges may be cracked at lesions margins. Lesion tissues are brown beneath the branch/trunk bark.||Cankered areas should be pruned out, making cuts 3-5 inches beyond the lesion edge. Disinfect shears between cutst.|
|Pansy||Botrytis Bud Rot||Buds become brown, sometimes with gray over-tones.||Sanitation. See 1998 recommendations.|
|Pansy||Myrothecium Crown Rot||Plants wilt and yellow and dieback. Crowns become brown and limp; sometimes tiny white & black cushions are visible on crowns.||Sanitation. Daconil treatments may give some protective control.|
|Pansy||Pythium Crown Root Rot||Dark brown, water-soaked decay at crown area.||Sanitation. See handbook.|
|Pansy||Thielaviopsis Root Rot||Black lesions on stunted roots. Plants stunted.||Sanitation. See handbook.|
|Pine, Loblolly||Sooty Mold||Black, sooty layer develops on needles. Black layer may be powdery or as thin dry sheets on needle surfaces.||Physically remove superficial coatings. Identify and control insects (may be aphids, scales, or other sucking-mouth parts insects).|
|Poinsettia||Botrytis Blight (Greenhouse location)||Gray-brown blotches on foliage; during humid conditions a delicate fungal wet may be present over blotch areas.||Increase temperatures; decrease humidity; sanitation; see Ala. Pest Management Handbook.|
|Poinsettia||Pythium Root Rot (Greenhouse location)||Roots are brown and water-soaked; outer root tissues slide easily away from inner root core.||Sanitation; See AL. Pest Management Handbook.|
|Pothos||Bacterial Leaf Spot (Erwinia)||Angular, dark, water-soaked spots on foliage.||Sanitation; Do not irrigate over-head.|
|Rose||Crown Gall (Agrobacterium)||Hard, rough-surfaced galls on the lower cane near the soil-line and on the roots.||Remove infected plants. Keep area free of susceptible plants for 2-3 years. Avoid wounds.|
|Snapdragon||Rhizoctonia Stem Canker||Brown Sunken Cankers on lower stems.||Sanitation; Cleary's 3336 or Domain.|
|St. Augustine||Brown Patch (Rhizoctonia)||See Centipede.||See Centipede.|
|Tulip||Penicillium Bulb Rot||Brown blotches on bulb, sometimes with green/gray spore masses.||See AL. Pest Management Handbook for dip recommendations.|
|Vinca||Phytophthora Root Rot||Roots are brown, water-soaked and the surface tissues will slip easily off the central root cylinder with a small amount of pressure.||Sanitation. See AL. Pest Management Handbook.|
|Vinca||Pythium Root Rot||Roots are brown, water-soaked and the surface tissues will slip easily off the central root cylinder with a small amount of pressure.||Sanitation. See AL Pest Management Handbook.|
|Vinca||Thielaviopsis Root Rot||Roots show black lesions and blotches. Tops grow poorly.||Keep potting mix or soil pH on the low side of normal, about 5.5-6.0. Cleary's or Domain drenches may help.|
WE 'EXTENSION PLANT PATHOLOGY FOLKS' WISH YOU ALL A HAPPY AND RESTFUL HOLIDAY SEASON!
January 25-27, 2001:
3rd Annual Gulf States Horticultural Expo.
Convention Center, Mobile, Alabama
For more information contact the GSHE office by phone at 334-502-7777; fax at 334-502-7711 or by e-mail firstname.lastname@example.org
January 27-31, 2001:
Southern Region American Society for Horticultural Science Annual Convention.
Fort Worth, TX. Contact Paul Smeal at 1107 Kentwood Drive, Blacksburg, VA 24060-5656, 540-552-4085; fax 540-953-0805, e-mail email@example.com
August 2-5, 2001:
SNA 2001 - Southern Nurserymen's Association Researcher's Conference and Trade Show.
Georgia World Congress Center, Atlanta, GA. Contact SNA at 770-973-9026; SNA Infoline at 770-973-4636; http://www.sna.org
January 27 - January 31, 2001:
Southern Region American Society for Horticultural Science Annual Convention.
Fort Worth, TX. Contact Paul Smeal, 1107 Kentwood Drive, Blacksburg, VA 24065-5656; phone 540-552-4085; fax 540-953-0805; e-mail: firstname.lastname@example.org
March 20 - March 30, 2001:
The Magnolia Society Conference and Tour of Ireland.
For more information write to Jim Gardiner, RHS Garden Wisley, Woking, Surrey GU23 6QB
August 2-5, 2001:
Southern Nursery Association Resarcher's Conference and Trade Show.
Georgia World Congress Center, Atlanta, GA. Contact SNA at 770-973-9026; SNA Infoline: 770-973-9026; SNA Infoline: 770-973-4636; http://www.sna.org
September 30 - October 3, 2001:
Eastern Region International Plant Propagators' Society Annual Meeting.
Lexington, KY. Contact Margot Bridgen, 26 Woodland Road, Storrs, CT 06268; phone 860-429-6818; e-mail email@example.com
October 12-13, 2001:
Middle Tennessee Nursery Association Horticultural Trade Show.
McMinnville Civic Center, McMinnville, Tennessee
931-668-7322; fax 931-668-9601; e-mail firstname.lastname@example.org; www.mtna.com or www.tnnursery.com/mtna
October 18-21, 2001:
Southern Region International Plant Propagators' Society.
Houston, TX. Contact David Morgan at 817-882-4148; fax: 817-882-4121; SR IPPS, P.O. Box 1868, Ft. Worth, TX 76101; e-mail: email@example.com
Send horticultural questions and comments to firstname.lastname@example.org.
Send questions and comments to email@example.com.
Letters to Bernice Fischman - 101 Funchess Hall - Auburn University, AL 36849.