March 2002

Tilt Ramblings:

March has roared in like a lion. I hope your plants were jammed, crammed and covered (sounds like a Waffle House hash brown order).

A disappointing note to start into spring is that the Agricultural Commissioner, Charles Bishop, after soliciting the Alabama Nurserymen’s Association’s suggestions for potential use of the Specialty Crops Promotion Funding, ignored the largest and one of the smallest segments of specialty crops in Alabama. The Green Industry farmers and the Christmas Tree producers received no assistance and all the money went to the Fruit and Vegetable Industry. Most of our surrounding states with strong nursery industries received assistance. Of course we are happy for the fruit and vegetable farmers and know they can use the help too.

Eight hundred thousand dollars was involved. We had requested $50,000 to $70,000 to get an economic survey of our industry so we could better market ourselves and our products. We had asked for assistance in starting an Evaluation and Distribution of New Crops Program similar to the Gold Medallion program in Mississippi or the Texas Superstar plant promotion program. Other surrounding states have similar successful marketing programs. We requested $50,000 as seed money for this project.

Of the $800,000 given to Alabama for the program, $100,000 was allocated to Tuskegee University, $25,000 was invested in international trade opportunities, $50,000 to help promote sweet corn producers in Baldwin County, $50,000 to help producers incorporate plasticulture into their production program, $50,000 for a Grading/Packaging/Labeling system for Satsuma oranges, and the remainder of funds will be used to promote Alabama produce.

You should be receiving your Declaration of Beneficial Use forms from the Alabama Water Reporting Program. There was a recent educational commodity meeting sponsored by ALFA where information was presented on the regulations and reporting procedures. I called Leslie Durham, an engineer in the Water Resources office to get information that could be easily accessed by you at your nursery. She said it was not posted yet but would be within the next 2 weeks. Reporting is a requirement for anyone pumping or having the potential to pump over 100,000 gallons of water per day. It is important for you to keep records even if you are not pumping this amount. If (more appropriate is when) a drought comes and water is rationed, you will need to be able to offer support for your water needs. You can get more information when this office has it available. Contact information is as follows:

Office of Water Resources
Leslie Durham
Enviromental Engineer
Montgomery AL
334-242-5506
www.adeca.state.al.us
Email - leslied@adeca.state.al.us


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:

ANSWERS FOR IMPORTERS

ALABAMA PESTICIDE INFORMATION

2003 PERENNIAL PLANT OF THE YEAR

ANOTHER GREAT AUBURN WEB SITE: HIGHLIGHTS

HYDRANGEAS - BEGINNING TO END

INCORPORATING CONTROLLED-RELEASE FERTILIZER INTO ROOTING SUBSTRATE

APHIDS AND ANTHROPODS

GROWTH AND MORTALITY OF DOGWOOD CULTIVARS IN ALABAMA

THIDIAZURON INCREASES SHOOT FORMATION IN NANDINA

SPURGE CONTROL

PLANT PATHOLOGY REPORT

UPCOMING EVENTS


ANSWERS FOR IMPORTERS

In recent years, the amounts of nursery stock, plants, and other propagative plant material, like bulbs and seeds, imported into the United States has grown dramatically. The expanded trade in these commodities has placed a grater demand on the U.S. Department of Agriculture's (USDA) inspection services. It has also presented new challenges in better understanding the pests and potential pest risks associated with the importation of these commodities from a wider variety of sources. Consequently, the need for verifiable information provided in a phytosanitary certificate, or similar documents deemed acceptable by USDA, has become vital with respect to each shipment of nursery stock, plants, and other propagative plant material.

USDA will therefore begin consistently and routinely enforcing an existing requirement that a phytosanitary certificate of inspection, or similar documentation approved by USDA, accompany these restricted articles, other than certain greenhouse-grown and stickered plants or specially certified seeds from Canada, that are offered for importation into the United States under our foreign quarantine regulations for nursery stock, plants, roots, bulbs, seeds, and other plant products (7 CFR 319.37).

This action, which began on January 22, 2002, is necessary to more effectively mitigate the risk of introducing foreign plant pests that could damage agricultural production and natural resources of the United States. The policy will become effective for seeds arriving from Canada through the mail on July 22, 2002.

Importers should check with their broker, vendor, or greenhouse to determine if the facility is part of the greenhouse or seed certification program in Canada that produces exempted greenhouse-grown plants or certified seeds. Information about the certification program in Canada can also be found at the following web site: www.inspection.gc.ca/english/plaveg/protect/dir/d-96-12e.html. Seed shipments arriving from Canada may be accompanied by either a phytosanitary certificate issued by the Canadian Food Inspection Agency (CFIA), or a seed analysis certificate (SAC) issued by an authorized laboratory.

All other nursery stock, plants, roots, bulbs, seeds, and other plant products must be accompanied by a phytosanitary cerificate issued by the plant health officials where the product originated in order to be considered for entry into the United States.

WHAT ARE PHYTOSANITARY CERTIFICATES?
A phytosanitary certificate documents the origin of the shipment and confirms inspection in the country of origin by a member of that country's national plant protection organization. This helps ensure that the shipment of commodities is free of injurious plant pests and diseases. The certifying country usually charges a fee for providing these certificates.

Phytosanitary certificates are governed under the International Plant Protection Convention, a multilateral treaty acknowledged by the World Trade Organization as the source for international standards for phytosanitary measures affecting trade. Phytosanitary certificates are recognized as an internationally accepted form of pest risk mitigation.

Summary
This action does not entail new regulatory requirements. Rather, its goal is to enforce an existing phytosanitrary certificate requirement on a mandatory, consistent basis. Importers and members of the general public will not be allowed to import restricted nursery stock, plants, or other propagative plant material into the United States without an accompanying phytosanitary certificate - unless the items are certain greenhouse-grown and stickered plants or specially certified seeds from Canada. Phytosanitary certificates must be obtained from an official agency of the country where the goods originate.

For questions on this regulation contact the USDA state plant health director nearest you. A list of USDA offices can be found in the phone book or on the Internet at www.aphis.usda.gov. Click on "plant health", and then on "directories and general information."

(from the United States Department of Agriculture Animal and Plant Health Inspection Service factsheet).

ALABAMA PESTICIDE INFORMATION

from Wheeler Foshee, Pesticide Education Specialist, Auburn University

PRIVATE APPLICATOR TRAINING MEETINGS
There is a federal mandate to teach farmers the correct and safe methods of pesticide application. If you are a county agent conducting these PAT meetings please use the slides and videos provided by the Alabama Cooperative Extension System. Administer and grade the tests (70% is a passing grade) and send results and a check for the $15 fee to the Department of Agriculture and Industries (ADAI) in Montgomery. Contact Wheeler Foshee at 334-844-5509 with questions.

FQPA NEWS
Home and residential use of organophosphates (OPs) are being cancelled with many agricultural uses remaining in some cases.

PHOSMET
EPA issued its final decision on phosmet (Imidan) on November 28, 2001. Highlights of that decision are:

  • 5-year time limited registration on peaches, apples, apricots, blueberries (highbush), crabapples, grapes, nectarines, pears and plums/prunes. The effects will be re-evaluated during the 5 years and could be canceled if suitable replacement chemistries are developed. An EPA release stated that:
    "EPA believes that the worker risks for these nine uses would outweigh the benefits appreciably, and that the current benefits are likely to diminish over time as new, safer alternatives become available and are adopted by growers."
  • During the next 5 years the registrant agreed to perform biomonitoring study of workers' blood cholinesterase levels and provide updated usage and benefits information and investigate the feasibility of developing additional protective equipment, specifically gloves for reentry workers.

GUTHION (azinphos-methyl)
In 1999 EPA found that the human risk associated with the use of azinphos-methyl (AZM) were mitigated by the lowering of residue tolerance for apples, pears, quinces, and crabapples. For peaches, the amount of active ingredient (AI) used was decreased.

The occupational risk assessment was completed and has the EPA worried. The "risk to field workers who re-enter AZM-treated sites to harvest, thin, prune and perform other post-application activities remains of particular concern," the IRED says.

In addition, EPA has concerns for some ecological risks associated with AZM use: particular freshwater and marine fish and invertebrates. EPA also found or claims that AZM is not essential for many crops and in only a small group of crops is it beneficial from an economic standpoint. Also, EPA says there are alternative controls available.

EPA has an agreement with the registrant to phase out the use of the product with many fruits and vegetables. There is a time-limited registration: the following will be allowed to be used for the next 4 years and could be extended if mitigation of worker risks are completed - apples, blueberries, nursery stock, southern pine seed orchards.

BENLATE
Benlate (benomyl) has been canceled by EPA in agreement with DuPont. On January 15, 2002, EPA published two Federal Register notices that outlines the final cancellation order which was effective on that date. Existing stocks can be sold until December 2002. You can view the FR notice at
http://www.epa.gov/fedrgstr/EPAFR-CONTENTS/2002/January/Day-15/contents.htm.

CYGON
The use of Cygon (dimethoate) for home owners appears to be on the way out. EPA received requests from the companies requesting that all residential uses be cancelled. This again is a result of reassessment through FQPA. This would include home gardens, buildings, recreational facilities or playgrounds. Agricultural uses proposed for cancellation are housefly treatments on farm buidings and structures, farm animal quaraters, and manure piles.

Dimethoate is a systemic organophosphate insecticide primarily used on a variety of field and orchard crops and ornamentals. EPA anticipates that it will grant the cancellation request and will allow a 1-year period for existing stocks to be sold.

ORTHENE
EPA received a request from Valent in November 2001 that uses for Orthene (acephate) that were indentified as risk concerns for residents, including children, be deleted. The uses that will be cancelled are: residential indoor and turfgrass sites (except golf courses, sod farms, and spot or mound treatment for fire ant control). Homeowners will not be able to use it on their turf for many pests. The final date of cancellation will be announced sometime this year.

GRASS CLIPPINGS TREATED WITH CLOPYRALID A CONCERN
If you compost your grass clippings you may want to avoid the use of clopyralid (Confront) on your lawn. It is used to control dandelions, clover, and other broadleaf weeds. Unfortunately it can persist at damaging levels for many broadleaf plants in compost.

Most herbicides break down during the composting process, but herbicides with the pyridine carboxylic group break down very slowly. These herbicides are not a serious health threat to animals, but tomatoes and some other broadleaves in a garden could be affected. If you or your lawn-care company uses clopyralid and you compost, use a separate pile that could be spread back on the lawn.

RECERTIFICATION MEETINGS
Pre-approval is required for commercial pesticide applicator meetings promoting recertification points. A letter of request should include the title of the meeting, the sponsor, the location, and the date(s), as well as a detailed agenda outlining the meeting session(s), speaker qualifications/information, date and time. The letter of request should be sent in at least one month prior to the scheduled meeting date. Each meeting must include at least a four-hour pesticide/herbicide presentation (can include industry updates, legal issues, safety and equipment calibration, etc.). Ten recertification points are awarded for attendance at such meetings or conferences and a certified sign-in sheet is sent out to the agency requesting approval. After the meeting the certified sign-in sheet of all attendees requesting Alabama recertification points must be returned to the Alabama Department of Agriculture and Industries. If you have questions call Dr. Pat Morgan with ADAI (334-240-7239) or Wheeler Foshee (334-844-4940).


2003 PERENNIAL PLANT OF THE YEAR

Leucanthemum superbum 'Becky' is Perennial Plant Association's 2003 Perennial Plant of the Year. This shasta daisy was introduced by Jim and Becky Stewart of Decatur, Georgia. It reaches up to 4 feet tall and doesn't need staking. The 2002 winner is Phlox paniculata 'David.' For more information go to http://www.perennialplant.org/.
(from Todd Davis, editor of Weekly NMPRO email, March 5, 2002).


ANOTHER GREAT AUBURN WEB SITE - HIGHLIGHTS

Highlights is the magazine of research from the Alabama Agricultural Experiment Station at Auburn University. It would be a great site to bookmark as you will find information on a wide range of topics. Two articles in the current issue are of special interest to our readers. The first is on the control of imported fire ants in Alabama. Phorid flies are being used in the battle against this very difficult pest. The other article deals with the control of annual bluegrass, a very hardy plant that threatens turfgrass.

The URL is as follows:
http://www.ag.auburn.edu/resinfo/highlightsonline/index.html Click on Current Issue


HYDRANGEAS - BEGINNING TO END

‘Hydrangeas - Beginning to End’ will be held on May 31-June 1, 2002. The meeting, sponsored by the Center for Applied Nursery Research (CANR), is being held at the Augusta Technical College, Thomson McDuffie Campus, 388 Tech Drive, NW, Thomson, GA. Also included is a site visit to the CANR research facility in Dearing, GA. The meeting is scheduled from 1:00 to 7:00 PM on Friday, May 31 and from 8:30 AM - 4:30 PM on Saturday, June 1, 2002.

The CANR provides funding and a protected site for horticultural research under commercial growing conditions. Part of its mission is to disseminate information of interest to the horticulture industry. Presentations by nationally and internationally known experts will present a wide array of information on hydrangeas, from breeding and growing to landscape design and floral arrangements. Anyone with an interest in hydrangeas - growers, florists, designers, landscape contractors, garden center managers or avid gardeners - will enjoy and learn from the guest speakers’ presentations during the two day meeting.

Over the past few years CANR has funded several projects related to the production of hydrangeas for the retail market. Currently, they have about 4500 hydrangeas in breeding projects, pruning studies, and bloom-color manipulation studies at CANR that should be in bloom at the time of the meeting. In the breeding program, Dr. Michael Dirr, University of Georgia, is searching for new and superior Hydrangea macrophylla and H. paniculata cultivars with good disease resistance, compact growth habit and reblooming characteristics. Dr. Jim Midcap, University of Georgia, has been working with manipulation of Hydrangea macrophylla blossom color. Tabor Conwell and Dr. Ken Tilt, Auburn University, are currently studying the effect of pruning times on spring bloom of 4 varieties of Hydrangea macrophylla. Sessions are as follows:

The Genus Hydrangea - Current Status and Breeding Opportunities
Dr. Sandra Reed, Research Geneticist, U.S. National Arboretum

Hydrangea Propagation: Duh! Look, I Can Do It!
Lisa Bartlett, ItSaul Plants, Atlanta, GA

Hydrangea macrophylla Flower Development and Cold Hardiness
Jeff Adkins, North Carolina State University, Raleigh, NC

Success with Hydrangeas: Greenhouse Forcing
Dr. Doug Bailey, University of Georgia, Athens, GA

The Natives are Restless, Hydrangea quercifolia and H. arborescens for the Garden and Landscape
Elizabeth Dean, Wilkerson Mill Gardens, Palmetto, GA

The ‘Cutting’ Edge of Hydrangeas
Donna Mills, Floral & Hardy Specialty Cut Flower Farm, Lexington, SC

A Celebration of Eccentricities - The Plants and Their People
Tony Avent, Plants Delights Nursery, Raleigh, NC

Hydrangea Cold Hardiness in the Landscape
Richard Bir, Extension Specialist, North Carolina State University, Fletcher, NC

Wydrangeas? Abuses and Excuses for Cultivating and Designing with Hydrangeas and their Kin
Rick Crown and Richard Simpson, Madison Gardens, Madison, GA

Exciting Hydrangeas for the Deep South
Ted Stephens, Nurseries Caroliniana, North Augusta, SC

Hydrangeas: Drying, Dyeing and Decorating
Judith King, Hydrangea Enthusiast, North Augusta, SC

Floral Arrangements: Hydrangea Blooms - Fresh Cut and Dried Hydrangea Blooms
Elizabeth Richards, Owner, Richards’ Flower & Gift Shop, Instructor, Augusta Technical College, Thomson, GA

PLANT INTRODUCTIONS, RESEARCH PROJECTS AND AUCTION:

Dr. Michael Dirr, University of Georgia, Athens, GA
Dr. Dirr is a University of Georgia horticulture professor and author of Manual of Woody Landscape Plants, the most widely used horticulture teaching and reference text in the country. His lifelong passion for horticulture has positively influenced a generation of students, gardeners, nursery professionals, and plants people. His teaching, research and writing endeavors have advanced the art and science of horticulture and gardening. His Georgia Plant Introduction Program has introduced 64 cultivars to the nursery trade.

‘Coach’ Vince Dooley, University of Georgia, Athens, GA
In addition to football, horticulture is of great interest to ‘Coach’ Dooley and he will be here to discuss Hydrangea macrophylla ‘Dooley’, a new hydrangea named for him.

Penny McHenry, American Hydrangea Society, Atlanta, GA
Penny founded the American Hydrangea Society in 1994. Her garden, which is full of hydrangeas, has been featured on Home & Garden TV twice and in many newspapers and magazines. She grows all the species she can obtain and includes lots of vines with her collection.

Dr. James T. Midcap, University of Georgia, Athens, GA
An Extension Specialist with the University of Georgia since 1987, Jim does applied container nursery production research and is faculty liaison with the Center for Applied Nursery Research. As an extension specialist he provides grower support through problem solving and up-to-date information. He, also, provides Extension Agent training on plant identification and nursery production.

Dr. Ken Tilt, Auburn University, Auburn, Alabama
Dr. Ken Tilt has been an Extension Horticulturist at Auburn University for 13 years and has the primary responsibility of serving the Nursery Industry in Alabama. He also supports the Christmas Tree Industry, Master Gardener program and the Urban Forestry Industry. His research supports his extension work and looks at nursery production systems as well as plant selection, evaluation and introduction

The pre-registration deadline is April 30, 2002. For further information including a conference schedule, speaker profiles, hotel and directions to the meeting site contact the Center for Applied Nursery Research at 4904 Luckey’s Bridge Rd. SE, Dearing, GA 30808, phone: 706-597-8309 or email: canr@thomson.net


NOTE: The following five articles are summaries of research presented in the March 2002 issue of the Journal of Environmental Horticulture. If you would like further information on the articles see the citation at the base of the article or email us to help you get a copy of the entire article.

INCORPORATING CONTROLLED-RELEASE FERTILIZER INTO ROOTING SUBSTRATE

The objectives of this study were to:

1. Compare adventitious rooting and subsequent growth of rooted liners of three herbaceous taxa (Artemisia ludoviciana 'Valerie Finnis', Gaura lindheimeri 'Whirling Butterflies', and Nepeta x faassenii 'Six Hills Giant') in response to two formulations of Controlled Release Fertilizers (CRF) incorporated into the propagation substrate. The two fertilizers were Nutricote 13-13-13 Type 180 and Nutricote 18-6-8 Type 180.

2. Determine optimal levels of incorporated CRF to accelerate plant growth.

Upon completion of the study, it was found that incorporating controlled-release fertilizer into the rooting substrate had no impact on adventitious rooting percentage and little influence on root number or root dry weight. It did improve visual appearance of the plants as well as their shoot dry weights. However, the greater response for shoot growth relative to root growth suggests that Nutricote promotes shoot growth more than root growth, which can potentially influence the quality of the liner.

(from "Effect of Incorporating Controlled-release Fertilizer on Adventitious Rooting and Growth of Artemisia, Gaura, and Nepeta by D. Bradley Rowe and Bert M. Cregg from the Department of Horticulture, Michigan State University, East Lansing, MI, published in the Journal of Environmental Horticulture, March 2002).

APHIDS AND ANTHROPODS

Ascelpias species are used in perennial gardens because of their aesthetic attributes and as nectar sources and larval food plants for Monarch butterfly larvae. In this study Ascelpias species and cultivars were evaluated for differences in susceptibility to oleander aphids and large milkweed bugs. Insecticides were evaluated for their degree of aphid suppression and for non-target effects on natural enemies of the oleander aphid.

The only species that did not become infested with milkweed bugs in this 2-year study were A. syriaca and A. sullivantii. Plants with the lowest number of aphids, the highest plant quality ratings and the highest number of Monarch larvae were gooseplants, A. physocarpa. A. tuberosa cultivars also ranked high among all species tested. All evaluated products: Endeavor (pymetrozine), Orthene (acephate), Merit (imidacloprid), Tempo (cyfluthrin) and Mpede (insecticidal soap) effected short-term reductions in aphids in field plots. Reinfestation occurred within two to three weeks. Parasitoids and predators were also suppressed to varying degrees by materials applied.

(from "Effects of Cultivar and Insecticide Choice on Oleander Aphid Management and Arthropod Dynamics on Asclepias Species" by S. Kris Braman and Joyce G. Latimer, Department of Entomology, University of Georgia, Georgia Experiment Station, Griffin, GA, published in the Journal of Environmental Horticulture, March 2002).

GROWTH AND MORTALITY OF DOGWOOD CULTIVARS IN ALABAMA

An open-field evaluation of 38 dogwood (Cornus) cultivars was conducted in central Alabama from May 1996 to March 1998. Based on plant mortality, the study demonstrated that flowering dogwood cultivars are better performers in the full sun than giant dogwood, kousa dogwood, or kousa x flowering dogwood hybrids. Of the flowering dogwood cultivars with white bracts and green foliage, 'Barton', 'Cloud 9', 'Fragrant Cloud', 'Ozark Spring', and 'Welch Bay Beauty' showed the fastest growth rates, while 'Autumn Gold' and Wonderberry showed the slowest growth rates. 'Cherokee Brave', 'Cherokee Chief', 'Pink Beauty', and f. rubra grew the fastest among those cultivars with red or pink bracts and green foliage. Among the cultivars with variegated foliage, 'First Lady' showed better growth and survival than Cherokee Sunset or 'Rainbow'.

Below are photographs of three fast growing cultivars from the study:

Cornus florida Welch Bay Beauty Cornus florida Cherokee Chief Cornus florida Barton

(from "Growth and Mortality of Dogwood Cultivars in Alabama" by B.R. Hardin, D.J. Eakes, C.H. Gilliam, G.J. Keever, and J.D. Williams, Department of Horticulture, Auburn University, published in the Journal of Environmental Horticulture, March 2002).

THIDIAZURON INCREASES SHOOT FORMATION IN NANDINA

A study conducted from 1997 to 2000 determined the effects of thidiazuron (TDZ) on shoot formation, whole plant size, and phytotoxicity in Nandina domestica 'Harbour Dwarf' and 'Compacta'. Although exceptionally popular landscape plants in the South, nandina cultivars form new shoots slowly during container production, often limiting the availability of cuttings and increasing production time, even when plants are pruned. Single foliar sprays of Dropp (TDZ), a cotton defoliant with cytokinin properties, applied at up to 4000 ppm promote shoot formation and fuller appearing plants of 'Harbour Dwarf' and 'Compacta' nandinas within 30 days of application with minimal phytotoxicity or effects on plant size. Substrate drenches, while effective in stimulating branching, resulted in foliar distortion, necrosis, and in many cases plant death, are therefore not recommended.

(From "Thidiazuron Increases Shoot Formation in Nandina" by G.J. Keever and D.A. Findley, Department of Horticulture, Auburn University, published in the Journal of Environmental Horticulture, March 2002).

SPURGE CONTROL

Four experiments were conducted to evaluate herbicides for postemergence prostrate spurge (Chamaesyce prostrata (syn. Euphorbia prostrata)) control and tolerance of container-grown liriope (Liriope muscari).

Growers are often reluctant to apply preemergence herbicides immediately after potting up divisions of liriope (Liriope muscari) due to potential root inhibition. However, not using a preemergence herbicide often results in heavy weed infestations, including prostrate spurge. This research demonstrated that a single application of either Finale (glufosinate) at 1.2 kg ai/ha (1 lb ai/A) or Roundup (glyphosate) at 1.8 kg ai/ha (1.6 ai/A) provided excellent postemergence control of mature spurge. Finale caused slight initial injury, however plants grew past the injury in the normal production cycle. Roundup did not cause any injury, though some slight sporadic injury was observed when smaller plants were treated. Neither herbicide reduced liriope growth or bib numbers the spring following application. These data indicate that Finale and Roundup can be used as a cleanup treatment for postemergence spurge control in container-grown liriope when growers have delayed their preemergence herbicide applications until plants are rooted, or when failures in the preemergence weed management program occur.

Growers should use caution in applying Roundup or Finale to nursery crops and should conduct trials prior to treating their entire stock. The most effective weed control is provided by using sound sanitary and cultural practices and a proven preemergence herbicide program to prevent weed populations from becoming established in container stock. Nonetheless, the results of this research provide growers with another option when they have delayed preemergence herbicide applications until liriope are rooted or when failures in their preemergence weed management program occur.

(from "Postemergence Prostrate Spurge (Chamaesyce prostata) Control in Container-Grown Liriope" by J.E. Altland, C.H. Gilliam, and J.W. Olive, Horticulture Department, Auburn University, published in the Journal of Environmental Horticulture, March 2002.)


PLANT PATHOLOGY REPORT

JANUARY PLANT DISEASES FROM THE
AUBURN AND BIRMINGHAM PLANT DIAGNOSTIC LABS

AUBURN PLANT DISEASE REPORT- JANUARY
Jackie Mullen
Extension Plant Pathology Specialist

January started out seasonably cold, but warmed up to spring like conditions by the end of the month. Some azaleas and Japanese magnolias in Auburn had begun to show flowers opening! Our thirty plant samples in January came from landscapes and greenhouses.

Phytophthora cinnamomi root rot is a fairly well-known root disease of azaleas, rhododendrons, and related plants. Roots become brown, soft, and have a wet decay. The fungus is active at soil temperatures that range usually from 16°C-32°C. It usually causes problems during the warmer months of June, July, and August, but it will form resistant spores that will survive temperatures lower and higher than the 16-32°C range of normal growth and activity. It is not common for this disease to be active in January. The plant was sent from a Mobile area landscape, and it is possible that root disease may have been actively developing in January, but it is more likely that this disease had been most active last summer and fall. Obvious foliage symptoms may not have developed until roots were seriously damaged in late fall-early January. Foliage showed the lower leaf yellowing and browning along with dieback that is typical of root damage in woody ornamentals. Control of Phytophthora cinnamomi in landscapes involves removal of damaged plants; improved soil drainage and/or reduced irrigation, if appropriate.

There are several azalea cultivars that show some resistance to Phytophthora. See ANR-571 for a listing of these cultivars. If planting a Phytophthora-susceptible cultivar is planned, some soil replacement in the area may be helpful. Protective fungicide drench treatments are not usually recommended in landscape areas. These protective products are recommended in nurseries and sometimes in large landscape azalea plantings. See ANR-571 for more comments on control of this disease in nursery settings.

Downy mildew is a commonly seen problem in the early spring on a variety of vegetables. Crucifers in greenhouses and gardens are often bothered by this disease when conditions are cool and wet. Leaf infections usually begin as pale yellow or pale white irregular spots of varying size and shape. A thin gray mold may be seen on the lower surfaces of leaf spots when conditions are humid and wet. Use of a hand lens in the ‘field’ will greatly enhance the ability to see this mold. As spots age, they typically become dark gray or black. The downy mildew leaf spots we saw were dark gray-black. Moist chamber incubations produced the diagnostic gray mold with spores of Peronospora parasitica. Plants we examined also showed some irregular bleached areas or blotches on leaves and stems. These spots were not typical of disease, and we suspect that some type of spray burn may have occurred. Downy mildew problems in a greenhouse or garden can usually be controlled well by a regular spray schedule with a protective fungicide. See the Alabama Pest Management Handbook for a listing of these products.

Pansy diseases this past month included landscape problems with Colletotrichum leaf spot and Pythium crown rot. Also, cold damage was noted on some plantings in Montgomery. Colletotrichum leaf spot is usually seen in spring and fall, but some periods of January were spring-like. Leaf spots are typically white, round, and about 2-4mm diameter. Sometimes the tiny black fruiting bodies of the fungus can be seen scattered over the leaf spot surface. This disease is usually controlled by sanitation and sometimes protective fungicide applications are recommended. See the AL Pest Management Handbook or ANR-1214. Pythium root rot is a common problem at wet locations. The lower stem becomes light brown in color; tissue is soft and rotted and pulls apart easily, leaving the plant foliage neatly separated from the root ball! This disease is very similar to Phytophthora crown rot. Root rots may also develop. See ANR-1214 or the AL Pest Management Handbook for protective fungicide drench treatments which are typically used only in greenhouse situations or very large landscape plantings. Damaged plants should be removed and water in the area should be reduced if appropriate. If pansies are to be replanted and the area will continue to be wet from time to time, soil replacement or fungicide treatment may be needed. The cold damage appeared as large bleached areas at stem tips, leaf edges, and on large areas of leaves and stems. Newest growth appeared to be normal.

Primula bacterial soft rot appeared as a brown, wet rot at the lowest stem areas of the plants. The symptoms could be confused with Pythium or Phytophthora crown rot. Microscopic study showed the presence of abundant quantities of bacteria, and culture work showed that fungal agents were not active. Usually soft rot bacterial decay follows after a wounding or other injury or weakness of the plant tissue. We are not sure what might have brought about this problem. There is no pesticide treatment typically recommended for control of bacterial soft rot. Complete removal of damaged plants was recommended. As insects may cause injuries, plants should be watched for indication of insect presence.

Brown patch (caused by Rhizoctonia solani) and take-all patch (caused by Gaeuammnomyces graminis var. graminis) disease spread and development on St. Augustine grass are not typical occurrences in January, but warm weather of this past January in locations of mid or southern state sections could have provided conditions favorable for fungal activity. See ANR-493 and ANR-823 for details and control of these diseases.

January 2002 Plant Diseases Seen In The Plant Diagnostic Lab at Auburn

PLANTDISEASECOUNTY
AzaleaPhytophthora cinnamomi Root RotMobile
Indian HawthornColletotrichum Leaf SpotMontgomery
Pansy Colletotrichum Leaf Spot Montgomery
Pansy Pythium Crown Rot Madison
PrimulaBacterial Soft Rot *
St. AugustineBrown Patch (Rhizoctonia)Coffee
St. AugustineTake-All Patch (Gaeumannomyces graminis graminis)Coffee, Montgomery
*Counties are not reported for greenhouse and samples.

BIRMINGHAM PLANT DISEASE REPORT - JANUARY
Jim Jacobi
Extension Plant Pathology Specialist

We received 50 samples for the month. Most of the samples were received in the last 10 days of the month as above normal temperatures prevailed. Botrytis blight was seen on several greenhouse-grown plants. Botrytis can attack all above ground parts of a plant at all stages of growth, but damage is most common on the more succulent tissues during cool, moist conditions. Symptoms on diseased tissues range from small, distinct, light-colored, water-soaked spots to extensive blighting and decay of blooms, leaves, and shoots of a wide range of plants (annuals, perennials, and woody ornamentals). This disease is an especially common problem in greenhouses. Botrytis produces masses of gray spores clusters on diseased plant tissue and can often be seen with the aid of a hand lens. Management of Botrytis in the greenhouse depends upon good sanitation and reduction of relative humidity. Routine fungicide sprays used against Botrytis have fostered the development of fungicide-resistant Botrytis strains, so check with your county extension agent for the latest recommendations when selecting a fungicide. Extension publication, ANR-753, (www.aces.edu/department/extcomm/publications/anr/anr-753/anr-753.html), provides additional information on the identification and control of Botrytis blight. Conditions were also favorable for Pythium blight on ryegrass. This disease is often seen during periods of favorable weather (extended periods of moist conditions with temperatures 55-65°F) from fall through spring. Symptoms include small, distinct, circular to irregular, grayish-green, watersoaked spots, usually several inches in diameter. These spots often appear greasy or slimy, and may enlarge to 1-foot in diameter on higher-cut turfgrass. ANR-594 (www.aces.edu/department/extcomm/publications/anr/anr-594/anr-594.html) provides information on how to make an accurate diagnosis and manage this disease problem.

2002 January Diseases Seen In The Birmingham Plant Diagnostic Lab

PLANTDISEASECOUNTY
AzaleaCercospora Leaf SpotShelby
AzaleaPoor DrainageJefferson
Basil Botrytis Cutting Rot *
Basil Rhizoctonia Stem Rot *
BoxwoodPhytophthora Root RotJefferson
BoxwoodPoor DrainageJefferson
CamelliaTea Scale, Undetermined VirusJefferson
Cherrylaurel, CarolinaCercospora Leaf Spot Jefferson(2)
ColeusBotrytis Blight *
ColeusPythium Root Rot *
Cryptomeria, JapanesePhyllosticta Needle Blight Jefferson
Forget-Me-NotFlea Beetle*
Geranium, ZonalHigh EC, Pythium Root Rot *
Geranium, ZonalLow pH *
Holly x ‘Emily BrunerTea ScaleJefferson
Holly, Japanese ‘Helleri’Black Root Rot (Thielaviopsis)Jefferson
JuniperPoor Drainage, MitesJefferson
LavenderBotrytis Blight *
Pansy Pythium Root and Crown Rot Etowah
Ryegrass, perennial Pythium Blight Jefferson, Shelby
*Counties are not reported for samples from commercial greenhouse and nursery operations.

UPCOMING EVENTS

April to October, 2002:
Floriade 2002.
See the AmeriGarden (5,400 square feet), part of the world horticulture exhibition in the Netherlands.
For more information call 808-961-6660 or visit
http://www.floriade.nl/ or http://www.amerigarden2002.com/

May 31 - June 1, 2002:
A Center for Applied Nursery Research Topical Meeting
Hydrangeas - Beginning to End
Augusta Technical College and the Center for Applied Nursery Research
Thomson and Dearing, GA
Call 706-597-8309; Internet: www.canr.org

July 12 - 15, 2002:
ANLA Convention & Executive Learning Retreat.
San Diego, CA. Contact ANLA at 202-789-2900; Fax, 202-789-1893
http://www.anla.org

August 1-4, 2002:
SNA 2002 - Southern Nursery Association Researcher’s Conference and Trade Show
Georgia World Congress Center, Atlanta, GA.
Contact SNA at 770-953-3311; Fax 770-953-4411; SNA Infoline, 770-953-4636; e mail: mail@mail.sna.org
URL: http://www.sna.org

August 11-17, 2002:
American Society for Horticultural Science and XXVI International Horticultural Congress & Exhibition.
Metro Toronto Convention Centre, Toronto, Ontario, Canada.
Contact ASHS at 703-836-4606, Fax: 703-836-2024, E-mail: ashs@ashs.org
URL: http://www.ashs.org
http://www.ihc2002.org

September 26, 2002:
Fletcher Field Day.
Ornamentals field day at the Mountain Horticultural Crops Research Station in Fletcher, North Carolina.
Contact Dick Bir (rbir@fletcher.ces.state.nc.us) for more information.

September 29-October 2, 2002:
Eastern Region International Plant Propagators' Society NA and IPPS Southern Region NA Annual Meeting.
Hunt Valley (Baltimore), MD.
Contact Margot Bridgen at 26 Woodland Road, Storrs, CT 06268; 860-429-6818, E-mail: mbippser@neca.com or Dr. David L. Morgan, 332 Warbler Drive, Bedford, TX 76021; ph. 817-577-9272; e-mail, dleemorgan@msn.com

October 4-5, 2002:
Middle Tennessee Nursery Association Horticultural Trade Show.
McMinnville Civic Center, McMinnville, TN
phone: 931-668-7322; fax: 931-668-9601; e-mail: mtna@blomand.net,
http://www.mtna.com/ or http://www.southeasternnursery.com/mtna/

January 15-17, 2003:
Mid-AM Trade Show.
Navy Pier, Chicago, IL. Contact: Rand Baldwin at 847-526-2010, Fax 847-526-3993, e-mail mail@midam.org
URL: http://www.midam.org

January 30 - February 02, 2003:
ANLA Management Clinic.
Louisville, KY.
Contact ANLA at 202-789-2900; Fax, 202-789-1893
URL: http://www.anla.org

February 23-26, 2002:
Plasticulture 2002.
30th American Agricultural Plastics Congress
Contact ASP at 717-238-9762, Fax 717-239-9985, e-mail pheuser@calabreseheuser.org
URL: http://www.plasticulture.org

July 15 - 20, 2003:
ANLA Convention & Executive Learning Retreat.
Location TBA. Contact: ANLA, 202-789-2900; Fax, 202-789-1893.
URL: http://www.anla.org

July 30-August 2, 2003:
SNA 2003- Southern Nursery Association Researcher’s Conference and Trade Show.
Georgia World Congress Center, Atlanta, GA.
Contact SNA at 770-953-3311; Fax 770-953-4411; SNA Infoline, 770-953-4636.
URL:http://www.sna.org

September 30 - October 4, 2003:
American Society for Horticultural Science Annual Meeting and 100th Anniversary.
Providence, RI.
Contact ASHS at 703-836-4606, Fax: 703-836-2024, E-mail: ashs@ashs.org
URL: http://www.ashs.org

October 3-4, 2003:
Middle Tennessee Nursery Association Horticultural Trade Show.
McMinnville Civic Center, McMinnville, TN
phone: 931-668-7322; fax: 931-668-9601; e-mail: mtna@blomand.net,
http://www.mtna.com/ or http://www.southeasternnursery.com/mtna/

October 5-8, 2003:
IPPS Southern Region NA.
San Antonio, TX.
Contact: Dr. David L. Morgan, 332 Warbler Drive, Bedford, TX 76021; phone 817-577-9272; e-mail, dleemorgan@msn.com

July 29 - 31, 2004:
SNA 2004 - Southern Nursery Association Researcher’s Conference and Trade Show.
Georgia World Congress Center, Atlanta, GA.
Contact: SNA 770-953-3311; Fax 770-953-4411; SNA Infoline, 770-953-4636
URL: http://www.sna.org

October 1-2, 2004:
Middle Tennessee Nursery Association Horticultural Trade Show.
McMinnville Civic Center, McMinnville, TN
phone: 931-668-7322; fax: 931-668-9601; e-mail: mtna@blomand.net,
http://www.mtna.com/ or http://www.southeasternnursery.com/mtna/

October 3-6, 2004:
IPPS Southern Region NA
Greenville/Spartanburg, S.C.
Contact: Dr. David L. Morgan, 332 Warbler Drive, Bedford, TX 76021; phone 817-577-9272; e-mail, dleemorgan@msn.com

Send horticultural questions and comments to ktilt@acesag.auburn.edu.

Send questions and comments to bfischma@acesag.auburn.edu.

Letters to Bernice Fischman - 101 Funchess Hall - Auburn University, AL 36849.