NOVEMBER - 2000

Welcome to Thanksgiving Month!

I am sorry to say the month began with the tragic news and shock of the death of Lee Howell of Rocky Creek Nurseries in Lucedale, MS. Lee was one of the nicest people I have been fortunate to know in the nursery business. I did not see him but 2 to 3 times each year but I was always greeted with a genuine, friendly handshake, a big smile and a warm thank you for our faculty’s work to support the industry. He gave so much of himself to help others and gave tireless support and leadership to IPPS and the other nursery associations. He is a tremendous loss to our industry but selfishly I will miss my warm greeting and our short talks each year. We offer our sympathy and support to his family.

I am nervous with excitement after returning from a lifelong dream trip to China with Dr. Jeff Sibley and two of our graduate students. It was a great learning experience for 2 weeks in Beijing, Xieng, Shanghai and Wuhan as well as enjoying a couple of 12 to 16 hour train trips cross country. Our trip had the purpose of looking for plant material for Zones 7, 8 and 9. Most plant expeditions target hardy plants. Ours was to look for heat tolerant plants with ornamental appeal for our landscapes. We also were able to take in the tourist attractions along the way.

We were elbow to elbow (often jammed) with happy, prosperous Chinese people for miles and miles in cities of 6 to 12 million people. The cities were bigger than life, modern and clean with everyone walking with cell phones pressed to their ears. Cranes dotted the skyline as evidence of continued building. Prices were very reasonable. We stayed in 4 star hotels for about 30 to 40 dollars a night. We saw the Great Wall, the Clay Soldiers and other tourist sites, ate their odd dishes of snake, cow stomach, live shrimp, lotus root, (no monkey brains or beetles) and other not so exotic foods. Most dishes were surprisingly good or at least exceeded my expectations. There were 21 McDonalds in Shanghai, Pizza Huts, KY Fried Chicken was very big, and Dairy Queens were spotted in a few places. So, when we got tired of killing and eating our food at the table, we visited familiar home grounds with burgers and fries that tasted exactly like home.

Once you got to the country, it was 100s of miles of farmland. You could tell that when change was ordered it was widespread. Someone apparently decided that buffer strips and windbreaks were good farm practices. So, for a few hundred miles, there were 6 rows of poplar trees planted 20 feet apart at the edge of fields. The same was true in the city. Street trees (3 to 4 inch caliper) were determined by someone to be desirable so trees were planted every 20 to 25 feet (I never saw the end) with 10 ft concrete stakes beside each one. China is big on the map and I guess, like the US, it is bigger in person. They set up traditional areas for the tourists to buy pandas, Buddha's, silk and everything else thought of as traditional Chinese. But, the natives shopped for western attire just like us. There was obviously some poverty and the standard of living was lower than in the US but again the western footprint was everywhere and exceeded my expectations.

It was a great plant collection adventure. While other pure botanists have scrounged across distant rivers and mountains crawling and fighting through the elements for rare plants, we were honored to be hosted by one of our former graduate students who is now Director of the Wuhan Botanical Gardens and 3 other botanical gardens. The gardens have already collected, labeled and planted 5000 of the more than 6000 available species. Unfortunately we were not there long enough to take full advantage of our opportunity but it was nice to walk (run) through the "grocery store" and pick out our jewels of choice. We brought back just 30 new species but hopefully we will return in April to visit the treasure room again. Fifteen of the species were seeds and 15 were cuttings. Some of the cuttings will be a long shot but it was worth a try. Our time was so limited that by the time we reached the gardens we literally ran through the collections like bees darting from flower to flower. Our collection will remain in quarantine at Auburn for 2 years before we can put them out for evaluation. This is a long-term project but one I think will be very fruitful and one we are committed to pursuing. As soon as we can get our slides processed, I will share some of the pictures of our plant treasures. I will leave off the tourist shots.

It is unfortunate that with the wealth of plant material available, the Chinese use of all these treasures was very limited in the city. You barely needed two hands to count the tree species. England is known for taking our native plants, improving on them and then selling them back to us. We could do the same for China. As someone said, if you could get around the bureaucracy, anything you marketed in China would be a success because of the huge number of people. It was a great trip and it revitalized the Plant Nut in me.

I hope everyone can make it to our North Alabama Field Day. The Alabama Nursery Association and Alabama Cooperative Extension Service are trying to do more daylong on-farm programs rather than the more expensive seminars. It is working out well with the Greenhouse programs. Come join us. I think you will enjoy it.

Ken


The following articles are featured in this month's Something to Grow On:

HAPPY BIRTHDAY, NELLIE!

CERCOSPORA NEEDLE BLIGHT ON LEYLAND CYPRESS

AUBURN UNIVERSITY CAPTURES RESEARCH MONIES

NEW DRAFT OF INVASIVE SPECIES MANAGEMENT PLAN

10-YEAR WOODY PLANT TRIALS

RELEASE OF NEW PECAN VARIETY

AUBURN WELL REPRESENTED AT AG EXPO

PLAN TO BE AT THE 3RD ANNUAL GULF STATES HORTICULTURAL EXPO

REMINDER: NURSERY FIELD DAY

NEW CERCIS CHINENSIS RELEASE

HELP FOR CITRUS GROWERS

MONTHLY PLANT PATHOLOGY REPORT

UPCOMING EVENTS

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.


HAPPY BIRTHDAY, NELLIE!

Many nursery producers should be celebrating the birthday of Ilex x ‘Nellie R. Stevens' (I. Cornuta x I. aquifolium) because she has been great for the industry. The Holly Society celebrated the birthday of this holly at its birth place of Oxford, Maryland. The plant originated from seed sown by Miss Nellie R. Stevens (1866-1942) from the Washington Botanic Garden in Washington, D.C. The other two seedlings remaining from the cross are two males, ‘Edward J. Stevens' and ‘Maplehurst'. Edward J. Stephens was Miss Stevens daughter and their house was named Maplehurst. Nellie was not officially introduced until 1954 when it was registered by Mr. Van Lennep through the American Association of Nurserymen (plant registration number 339). The Holly Society of America erected a plaque to celebrate the significance of this holly about 40 feet from the original Nellie which now stands about 35 feet tall.

(Adapted from an article by Charles Anderson from Holly Society Journal vol 18(3) 2000)

CERCOSPORA NEEDLE BLIGHT ON LEYLAND CYPRESS

by Austin Hagan
Extension Plant Pathologist and Professor, Auburn University

Cercospora needle blight is a common and occasionally damaging disease on Rocky Mountain juniper and Eastern red cedar, as well as on bald and Arizona cypress. Recently, nurseries and Christmas tree plantations in Alabama have reported damaging outbreaks of Cercospora needle blight on Leyland cypress. In field plantings, this disease tends to be more damaging to stressed trees or trees in otherwise poor condition.

Symptoms
Browning or blighting of the scales or needles, which typically starts on the inner portions of the lower branches near the base of the tree, progresses upward and outward toward the shoot tips. At advanced stages of this disease, all scales except the current years growth dies. Selected, highly susceptible trees may succumb to this disease. Typically, symptoms usually appear during the summer months.

Disease Cycle
Eastern red cedar and other native tree hosts are most likely the source of the causal fungus Cercospora sequoia. The fungus may be introduced into landscape plantings on disease B & B or container-grown nursery stock. The fungus overwinters in the needles and other host tissues. Spores of the causal fungus, produced during periods of wet weather in the spring and fall, are spread by air currents and wind-driven rain to healthy trees. Free water is needed for spore germination and successful infection of host foliage.

Control
In nurseries, protective fungicide sprays should provide good protection from Cercospora needle blight. For best results, begin sprays in mid- to late spring before fresh symptoms appear. Referring to the intervals listed on the table, repeat preventative sprays on Leyland cypress throughout the summer until the cooler, drier weather in October. Thorough coverage of the foliage is critical to the control of Cercospora needle blight. When spraying, be sure to use enough pressure to force the fungicide through the canopy to thoroughly wet the innermost shoots, especially those near the base of the plant. Fungicides cleared for the control of Cercospora leaf spot are listed in the table below. Note: the information concerning efficacy of fungicides for the control of Cercospora needle blight date back to the late 50's and 60's. No recent efficacy trials have been conducted with any registered fungicides.

Fungicide
Application Rate

Per GallonPer 100 Gallon
Comments
azoxystrobin
Heritage 50W
1-4 oz. Apply at first sign of disease and repeat every 14 to 28 days.
propiconazole
Banner Maxx
8-12 fluid ounce Apply every 30 days when conditions favor disease.
thiophanate-methyl
3336 50W
1 1/2 - 2t. 12-16 ounces Spray at 7- to 10-day intervals during humid, wet summer weather. Apply to drip. Use surfactant to improve coverage with wettable powdery formulations. Note: other formulations of the thiophanate-methyl are available and are also labeled for the control of this disease.
thiophanate-methyl
3336 4.5
1 T.10-20 fluid ounces
thiophanate-methyl
Zyban 79W
5 t. 3 lb.
t = teaspoon, T = tablespoon.


AUBURN UNIVERSITY CAPTURES RESEARCH MONIES

Specific funding items from Alabama from the FY 2001 Agriculture Appropriations bill included $475,000 for Satsuma Citrus Research and $285,000 for Nursery, Turfgrass and Sod Research. It was filed on Friday Oct. 6 and passed by the House and Senate on Wednesday, October 11. Congratulations to us!!!


NEW DRAFT OF INVASIVE SPECIES MANAGEMENT PLAN

The second draft of the Invasive Species National Management Plan was posted last week. Comments will be accepted for 45 days. “At first glance, it represents a huge improvement over the summer’s draft,” said Craig Regelbrugge, Senior Director of Government Relations at ANLA. “It looks like most of the really bad parts targeted at the horticultural industries have been removed or softened. Still, it will demand very careful review.” See http://www.invasivespecies.gov

(from Weekly NMPRO e-mail).

10-YEAR WOODY PLANT TRIALS

The United States Agriculture Research Service launched a new Web site that includes information from woody plant trials in the North Central United States. Ten-year performance evaluations are available for many trees, shrubs, vines and groundcovers, including maples, hydrangeas, rhododendrons, spireas, viburnums and weigelas. Go to:
http://www.ars- grin.gov/ars/MidWest/Ames/trialhmpge.html
(from Weekly NMPRO e-mail).

RELEASE OF NEW PECAN VARIETY

Nocano, a new pecan variety, was recently released by the United States Agriculture Research Service. Nocano is a cross between Cheyenne and Sioux and has good scab resistance and high-quality nuts. Scab is the most damaging disease to pecans east of Central Texas. The fungus attacks both pecan foliage and nuts. Nocano has been under evaluation in College Station, Texas, since 1986. For more information call: (979) 272-1402.

(from Weekly NMPRO e-mail).

AUBURN WELL REPRESENTED AT AG EXPO

Auburn University's ties to state horticulture were well represented at the 2000 Sunbelt Ag Expo in Moultrie, Georgia held on October 17th - 19th. Alabama was the Spotlight State this year and a large tent was erected which housed representatives of the state's best agricultural products and organizations. The Horticulture display featured photos from the Alabama Nurserymen's Association, The Alabama Christmas Tree Association, The Alabama Fruit and Vegetable Growers Association, Alabama Master Gardeners, and the Teaching, Research and Extension accomplishments at Auburn University.


PLAN TO BE AT THE 3RD ANNUAL
GULF STATES HORTICULTURAL EXPO

Final preparations are being made for the 3rd Annual Gulf States Horticultural Expo to be held at the Mobile Convention Center in Mobile, Alabama on January 25-27. Educational seminars will be held and the convention center floor will be crowded with 600 booths covering all areas of the horticultural spectrum, from plant suppliers to equipment dealers to southeastern university representatives. You won't be disappointed when you experience the range of the Expo, which is the combined effort of Alabama, Louisiana and Mississippi.


REMINDER: NURSERY FIELD DAY

On November 9, 2000, a variety of nursery professionals will come together to share information, tour the Huntsville Botanical Gardens, eat great barbecue at the S & S Nursery and tour their fields. The day will be sponsored by the Alabama Nurserymen's Association, the Huntsville and Madison County Botanical Gardens, S and S Nurseries, Inc., ALFA, the Alabama Cooperative Extension System and various equipment dealers. We will cover basic information in a beautiful setting. The schedule for the day follows:

8:00-8:30
Registration and Coffee Talk

8:30-9:00
Weed Control in the Field
Dr. Charles Gilliam
Auburn University

9:00-9:30
Making Your Herbicides Live Up to Their Name and Banding With Rigged Sprayers Designed for Nurseries
Mark Halcomb
Extension Nursery Specialist – University of Tennessee

9:30 – 9:45 Break

9:45 – 10:15
Monitoring Fertility: We Know We Need to Do It: Here's How.
Dr. Raymond Kessler
Auburn University

10:15 – 11:15
The Nursery Production System: Putting It All Together
Dr. Ken Tilt
Auburn University

11:15 – 11:45
North Alabama Horticulture Treasure: Quick Highlight Tour of the Gardens
Harvey Cotton
Director of Huntsville Botanical Gardens and Secretary-Treasurer of the Alabama Nurserymen's Association

11:45
Follow the Sweet Smell of Barbecue Smoke to S & S Nursery for Lunch and Field Demonstrations – Athens, Alabama

12:15 – 1:00
An Alabama "Be Still My Heart, Drooling, All You Can Eat, Pile It On, 20 Napkin Lunch"
Smoked to Perfection by Chef Strain

1:00 – 4:00
New Sprayer Demonstration, Irrigation, Mixers, Big and Little Tree Spades. See the equipment as it was meant to be shown, "doing their thing" in the field.

Growers and managers are encouraged to bring employees. This is an opportunity to share information and experiences with speakers, allied industry representatives, and other growers.

Please call or email:
Linda Van Dyke
Executive Director,
Alabama Nurserymen's Association
P.O. Box 9
Auburn, AL 36831-0009
Phone: 334-821-5148
alna@prodigy.net

Ken Tilt
Department of Horticulture
101 Funchess Hall
Auburn University, AL 36849
Phone: 334-844-5484
Fax: 334-844-3131
Ktilt@acesag.auburn.edu

to let us know if you are coming so that we can make sure you are seated and fed in Alabama style.
Registration fees are $5.00 per person or $25 per company (5 or more)

Good Information, Good People, Great Day: How could it be any different when nursery people get together? Join us for this special event. You will be glad you did!

DIRECTIONS to the Huntsville Botanical Gardens:

Traveling north or south on I-65, take I-565 East to Exit 15. Follow signs to Bob Wallace Avenue. The Botanical Gardens will be 1/2 mile on your right (next to the Space and Rocket Center).

DIRECTIONS to S&S Nurseries, Inc.
20830 Huntsville Brownsferry Road
Athens, AL

Take I-565 West to Highway 31 North; go to the 4th red light, turn right. The Nursery is 1/4 mile on the right.


NEW CERCIS CHINENSIS RELEASE

Last week, United States National Arboretum announced the release of ‘Don Egolf,’ a new Cercis chinensis cultivar. The redbud originated from seed collected in Kunming, China, is compact and profusely produces rose-purple flowers. It is easily propagated by cuttings, resistant to canker and hardy to USDA Hardiness Zone 4. (202) 245-4568.

(from T. Davis, Weekly NMPRO e-mail - 10/31)


HELP FOR CITRUS GROWERS

USDA has made money available to Florida citrus growers to replace fruit trees destroyed because of citrus canker infestation. Commercial grove owners can receive $26 per tree lost with a $2,704-$4,004 per- acre cap, depending on tree type. More than 700,000 commercial citrus trees have been destroyed in Florida to combat the disease. (202) 690- 2817.

(from T. Davis, Weekly NMPRO e-mail - 10/31)


PLANT PATHOLOGY REPORT

SEPTEMBER PLANT PROBLEM REPORT FROM THE AUBURN AND BIRMINGHAM PLANT DIAGNOSTIC LABS

Auburn Plant Disease Report-September (J. Mullen)

As with previous months, drought has caused and continues to cause damage to landscape areas. Some of the damage is directly drought related. Some damage was caused by over-watering, as homeowners tried to over-compensate for the dry conditions. Most of our samples were from landscapes.

An unusual sooty mold was identified on birch. The growth began as a thick yellow feathery mat covering the surface of the leaves. The feathery mat was about ¼-½ inch thick with the thickness composed of the feathery projections. As the mat aged, it became black. The mat did not penetrate the leaf tissues and it could be pealed off of the leaf surface. This fungus was tentatively identified (sexual spores were not present) as Microxyphium fagi (William Baker, Mycology). As with other sooty molds, control involves control of the insects which produced the 'honeydew' on the leaves.

A Phytophthora species (possibly two) was identified on blighted blossoms of greenhouse chrysanthemum. Tests are under way to confirm pathogenicity. Blossoms were partially and totally blighted.

A bacterial leaf spot was observed on several cultivars of Indian hawthorn. The diagnosis was made on the basis of the bacterial streaming observed microscopically. The exact identity of the bacteria has not, as yet, been determined. Bacterial leaf spot, in any situation, requires strict sanitation (removal of plants). Ground-level irrigation will help considerably.

Anthracnose leaf spots were noted on maple and Bradford pear. This foliage disease and other leaf spot diseases are often numerous in the early fall as senescing leaves seem to be more susceptible to fungal leaf spots. Usually, leaf spot diseases are not of great significance and sanitation of fallen leaves in the fall is the only recommendation given.

A number of the disease reports of September were root/crown rot problems. Phytophthora root rot was diagnosed in both woody and herbaceous samples of gardenia, English ivy, Shore juniper, and leyland cypress. Root decay caused by this fungus can cause death of the affected plant. Infected areas of lower stems (crowns) and roots decay as a soft rot in the presence of wet soil conditions. Phytophthora is a 'water mold' and, as such, it develops and causes disease spread and development only in wet locations. As infections age and plants begin to die, the rotted areas dry out. Disease may develop after plant roots have been stressed or injured by drought or excessive application of fertilizer. Then, when wet conditions occur, the environment is conducive for Phytophthora development with the weakened plants being more susceptible to disease.

The droughty conditions earlier in July-September may have stressed plants so that they were more susceptible to root disease when wet conditions finally occurred. Poorly draining soils are also conducive for Phytophthora root disease. Control in a nursery involves sanitation and water control and sometimes protective fungicide drenches. In homeowner situations, where situations involve a small number of plants, protective fungicide drenches are usually not a practical and economic recommendation. Crop rotation is sometimes helpful in the landscape situation. Pythium is another 'water mold' that usually causes root disease of herbaceous plants and foliage blights of certain turf grasses. Pythium may cause root disease of woody seedlings or severely stressed woody plants. In September, Pythium root decay was identified on gardenia, Shore juniper, long leaf pine, and St. John's wort. Disease symptoms are similar to the water-soaked description for Phytophthora. Usually culture or ELISA work is needed to distinguish between Pythium and Phytophthora. Control recommendations for Pythium root decay are similar to Phytophthora disease control. See the Alabama Pest Management Handbook for specific fungicide recommendations.

Hypoxylon canker on red oak was identified by the hard black stroma sections attached to bark pieces that were sent to the lab. The black, often thick, stroma (or body) of this fungus may be very destructive. Once trees are infected and stroma is produced between the wood and bark or in bark cracks, it is too late to apply remedy treatments. Infected trees should be removed to help prevent disease spread.

2000 September Plant Diseases Seen In The Plant Diagnostic Lab at Auburn
PLANT DISEASECOUNTY
BirchSooty Mold (Microxyphium fagi) Randolph
ChrysanthemumPhytophthora Blossom Blight *
GardeniaPhytophthora & Pythium Root Rot Lee
Indian HawthornBacterial Leaf Spot Escambia
Ivy, EnglishPhytophthora Stem & Root Rot Tuscaloosa
JuniperCercosporella Blight Russell
Juniper, Blue RugPestalotia Needle Blight Cleburne
Juniper, ShorePhytophthora and Pythium Root Rot Winston
Leyland CypressPhytophthora Crown Rot *
Leyland CypressPythium Feeder Root Rot *
MapleAnthracnoseHenry
OakOak Leaf Blister (Taphrina) Franklin
Oak, RedHypoxylon Canker Franklin
Pear, BradfordAlternaria Leaf Spot Russell
Pear, Bradford Anthracnose Russell
Periwinkle, AnnualPhytophthora Blight Lee
Pine, LongleafPythium Feeder Root Decay *
ZoysiaRust (Puccinia) Houston

*Locations are not reported for nursery and greenhouse samples.

Birmingham Plant Disease Report-September (J. Jacobi)

The ongoing drought continues to be the biggest contributor to plant problems received in the clinic. As turfgrass and ornamental trees and shrubs prepare for winter several areas in Jefferson and Shelby counties are under water restrictions. Unfortunately, the drought will have long-term effects, as plants under severe water stress are more susceptible to invasion by opportunistic fungi (Botrysphaeria and other canker diseases), to attack by borers, and to damage by severe winter weather.

During the last month, the leaves of many landscape plants are showing marginal scorch, and early fall coloration consistent with drought stress. Although we have not seen any samples in the lab this summer, bacterial leaf scorch can cause similar symptoms in sycamore, various oaks, and American elm. See ANR-1050 for more details on bacterial leaf scorch of shade trees. Leaf scorch caused by drought is generally uniform around the leaf margins, occurs over large areas of the tree canopy (one side or more), and may occur on more than one species of plant in the landscape. In contrast, bacterial leaf scorch is not uniform around the leaf margins, starts on selected branches, and is host specific. Definitive diagnosis of bacterial leaf scorch requires laboratory testing.

We have also received several samples of turfgrass (especially zoysiagrass) from patches of dead and dying grass with no sign of disease or insect damage. These spots may start rather small and enlarge in a circular pattern, and can resemble damage caused by diseases (such as dollar spot) or insects (such as grubs). In most cases, the soil below these patches is powder dry. These localized dry spots are often associated with shallow and/or heavy clay soil, thick thatch, south-facing slopes and other problems. As some have found out, these dry spots will not respond to fungicides or insecticides.

2000 September Diseases Seen In the Birmingham Plant Diagnostic Lab
PLANT DISEASE COUNTY
ArborvitaeMite Damage Jefferson
Azalea Phomopsis Dieback Jefferson (3)
BentgrassPythium Root Rot (2).
BoxwoodPhytophthora Root Rot Jefferson
BoxwoodMacrophoma Blight Jefferson
Cherry LaurelPhytophthora Root Rot/Overwatering Jefferson
Cypress, LeylandSeridium Canker Shelby
DogwoodLeaf ScorchJefferson
Holly, Dwarf YauponClylindrocladium Leaf Spot. Jefferson
Hosta Anthracnose Jefferson
Hydrangea, BigleafCercospora Leaf Spot Jefferson
Hydrangea, OakleafArmillaria Root Rot Shelby
Ivy, EnglishSunburn/Phyllosticta Leaf Spot Jefferson
Ivy, EnglishPythium Root Rot Jefferson
Mondograss
(Ophiopogon spp.)
Anthracnose Jefferson
NandinaMosaic (CMV) Jefferson
Oak, RedLeaf Scorch Jefferson
RhododendronPhytophthora Root Rot Shelby
Zoysiagrass Dollar Spot Jefferson

Disease Possibilities For October

Disease problems usually decline in October as temperatures drop and the summer field and garden crop season is largely over and the fall-winter plantings of small grains have not yet begun or are just beginning. But, we still commonly see forage problems, landscape ornamental problems, greenhouse/nursery crop problems. Drought damage effects will probably continue to be seen this fall through next spring.

At this time of year we often see pansy diseases. Watch for leaf spots, crown rots and root rots.

The list below includes some common disease problems received in the lab during October of the past few years. Comments on control practices are brief. Refer to the Alabama Pest Management Handbook or individual spray guides or fact sheets for details.

DISEASE DESCRIPTIONS AND BRIEF CONTROL COMMMENTS ON
SOME COMMON DISEASES OFTEN SEEN IN OCTOBER

.
PLANT DISEASEDESCRIPTION CONTROL
Aucuba Botryosphaeria Blight Black elongated lesions on stems cause a dieback. Also, black irregular lesions may develop on leaves. Sanitation; Cleary's, Domain or a benomyl labelled on ornamentals may help.
Azalea Cercospora Leaf Spot Brown circular or angular leaf spots of variable size. See the Alabama Pest Management Handbook under Rhizoctonia web blight.
Azalea Colletotrichum Leaf Spot Brown circular-irregular spots (2-3 mm) diameter. Sanitation; usually this is a stress related problem which develops in the fall.
Azalea Phomopsis Canker Brown, sunken, elongated stem lesions. Pruning 3 inches beyond the canker margins. Cleary's protective sprays after pruning may help.
Azalea Phytophthora Root Rot Brown, water-soaked root decay. Sanitation; protective fungicide treatments. See ANR-571.
Azalea Liners
and Containers
Rhizoctonia Root Rot Brown, dried dying roots. Sanitation. See Alabama Pest Management Handbook.
Azalea Liners
and Containers
Phytophthora Root Rot Brown, water-soaked dying roots. Sanitation. See Alabama Pest Management Handbook.
Boxwood Volutella Blight Brown stem cankers and leaf blight; orange wet spore masses. Sanitation; Cleary's 3336; remove stress.
Cactus, Christmas Fusarium Crown Rot Lower trunk becomes decayed with brown dried tissues.Sanitation. Do not save soil.
Calendula Rust (Coleosporium) Yellow-orange brown spots (0.3-0.8 cm diam.) with a yellow halo of 1-2 mm wide. Removal of calendula from close proximity to black pine and Scots pine (alternate hosts) may help.
Cedar Armillaria Root Rot Rapid or slow dieback; thin white mycelial mat under bark at soil line; thin black threads may be present under bark. Sanitation.
Chrysanthemum Alternaria Blight Dark Brown, irregular spots on foliage. Sanitation; see Alabama Pest Management Handbook.
Chrysanthemum Fusarium Crown Rot Lower stem becomes reddish brown, dried and dead; lesion may be one-sided on stem or may extend around entire stem. Sanitation; see Alabama Pest Management Handbook under Fusarium wilt.
Chrysanthemum Stem Blight,
Pseudomonos syringae
and Erwinia
carotavora.
Black, wet rotting of stem. -
Coleus Anthracnose
(Colletotrichum)
Circular-irregular brown lesions on foliage. Sanitation. Cleary's 3336.
Crape Myrtle Cercospora Leaf Spot Brown angular leaf spots of variable size. Sanitation and protective sprays of Cleary's 3336.
Cypress, Leyland Cercospora
(Asperisporium or Cercosporidium sequoiae) Lower Limb/Needle Blight
Lower limbs browned in spots with abundant (microscopic) sporulation of C. sequoiae. Sanitation.
Cypress Seridium Canker Sunken lesion on stem/branches. Sanitation.
Dianthus Pythium Crown Rot Lower stem becomes dark, and water-soaked. See the Alabama Pest Management Handbook.
Dianthus Rhizoctonia Crown Rot Lower stem becomes brown and dry rotted. Sanitation. See the Alabama Pest Management Handbook.
Dogwood Cercospora Leaf Spot Small (3-5 mm) brown, irregular spots scatttered over leaf surfaces. Sanitation.
Elm Powdery Mildew (Phyllactinia orUncinula) White, powdery dusting on leaves. Sanitation of leaves in the fall.
Euonymus Crown Gall (Agrobacterium tumefaciens) Woody irregular gall that encircles lower stem area. Sanitation; crop rotation.
Fatsia Phytophthora and Pythium Root Rot Roots become brown and water-soaked; the outer cortex will slip easily off the root central cylinder. Sanitation; remove wet conditions.
Fern, Boston Pythium Root Rot Outer root cortex easily slips from inner core; plants yellow and dieback. Sanitation; See the Alabama Pest Management Handbook.
Holly Botryosphaeria Canker Sunken, cracked lesions with brown decay under bark. Sanitation.
Holly Oedema Small (1-2 mm), raised, corky, light-medium brown spots on lower leaf surfaces. Reduce watering during cloudy weather; improve soil drainage.
Holly Phyllosticta Leaf Spot Small (2-4 mm diam.) irregular or circular brown leaf spot. Sanitation; see the Alabama Pest Management Handbook.
Hollyhock Pythium Root Rot See comments for Dianthus. Sanitation. Improve soil drainage.
Hollyhock Rhizoctonia Root Rot See comments for Dianthus. Sanitation. Cleary's 3336 protective drenches.
Hosta Root-Knot Nematode (Meloidogyne) Plants grow poorly. Root galls evident. Solarization of the area before replanting.
Hydrangea Cercospora Leaf Spot Brown angular leaf spots of variable size. Sanitation. See the Alabama Pest Management Handbook.
Hydrangea Alternaria Leaf Spot Brown oval leaf spots. Sanitation.
Impatiens Pythium Crown Rot Lower trunk becomes brown and soft-decayed. Sanitation; correct wet soil problem; see Alabama Pest Management Handbook.
Ivy, English Anthracnose (Colletotrichum) Irregular brown leaf spots (3-10 mm diam.) and dark brown elliptical lesions on stems. Sanitation; see Alabama Pest Management Handbook.
Ivy, English Phytophthora Stem, Root, and Leaf Rot Brown, water-soaked dying stems, roots, leaf area. Sanitation; see Alabama Pest Management Handbook.
Juniper Pestalotia Blight Sections of foliage turn brown and dead; stress related. Sanitation; remove stress condition.
Juniper Phomopsis Tip Blight Tip ends of branches turn brown. Blight moves from twig tips into inner foliage. Lower foliage may be affected first; seen more in nurseries than landscapes.Sanitation; Cleary's 3336 protective sprays. See the Alabama Pest Management Handbook.
Juniper Phytophthora Root Rot Feeder roots become brown and wet rotted. They eventually dry out.Sanitation. Solarization before replant may help. Improve water drainage
Juniper Seridium Canker Sunken, brown lesion on branches.Pruning 3-4 inches beyond the edge of canker; after pruning, protective Cleary's sprays may help.
Loquat Anthracnose (Colletotrichum) Brown irregular spots on leaves and stems; some large blotch areas along veins. Removal of fallen leaves; pruning of disease stem area; Cleary's protective sprays.
Maple Anthracnose (Colletotrichum) Irregular, spreading, brown lesions on leaves and small twigs. Leaf lesions may occur and develop along veins. Correct and remove all fallen leaves. Protective fungicides used only when trees are small.
Maple Cristulariella Zonate Leaf Spot Brown-gray zonate circular-oval leaf spots. Sanitation in the fall.
Maple Phyllosticta Leaf Spot Circular brown spots with dark brown or purple margins. Sanitation in the fall.
Marigold Alternaria Leaf Spot Angular or round black spots. Sanitation.
Monkeygrass Anthracnose (Colletotrichum) Brown blotches on leaves; sometimes blotches begin at leaf tips; black fruiting bodies may be visible as tiny black dots in lesions. Sanitation; Cleary's 3336 or Domain protective sprays.
Oak, Pin Xylella Scorch Disease Dieback with leaf edge scorch. Sanitation.
Orchid, Oncidium sp. Colletotrichum Leaf Spot Brown irregular spots. Sanitation; Cleary's 3336.
Pansy Anthracnose (Colletotrichum) Brown stem lesions (cankers) on lower stems. Also brown circular-irregular leaf spots of variable size.Sanitation. See the Alabama Pest Management Handbook.
Pansy Cercospora Leaf Spot Leaf spots are black, circular areas of feathery patterned discoloration. Sanitation.
Pansy Myrothecium Crown Rot Crowns brown and decaying with tiny black capped white spore masses. Sanitation. See A. Hagan.
Pansy Pythium Crown Rot and Root Rot Light-medium brown, water-soaked crowns and roots. Sanitation. See Alabama Pest Management Handbook.
Pansy Phytophthora Root Rot Roots become brown and water-soaked. Sanitation. See the Alabama Pest Management Handbook.
Pansy Pythium Root Rot/Crown Rot See description for Pythium. See Pythium.
Pansy Thielaviopsis Root Rot Black spots (lesions) on roots. Sanitation; Cleary's 3336 protective treatment.
Periwinkle (Vinca) Stem Canker(Colletotrichum); May be secondary Sections of lower stems become brown and dead. Sanitation. Cleary's 3336.
Periwinkle Pythium Root Rot Roots become brown, soft & rotted. Sanitation
Periwinkle Phytophthora Aerial Blight Sections of foliage become blighted. Stems develop brown lesions. Sanitation
Periwinkle Phytophthora Root Rot Roots become brown, soft and rotted. Sanitation.
Pine, Virginia Lophodermium (Ploioderma) Needle Cast Older needles turn brown and drop; very small (1-2 mm or 1/32 inch) football shaped, black fruiting bodies develop on browning needles. Protective fungicides sprays in the fall and spring. See Alabama Pest Management Handbook.
Poinsettia Bacterial (Erwinia) Stem Rot Black, water-soaked spots or lesions on stems. Lesions may girdle stems. Sanitation. See the Alabama Pest Management Handbook.
Poinsettia Fusarium Root and Lower Stem Rot Roots and lower stems become reddish-brown, dried and dead. Sanitation; Banrot drenches.
Poinsettia Pythium Stem and Root Rot Lower stems and roots become medium brown, soft, and watersoaked and rotted. Sanitation. See the Alabama Pest Management Handbook.
Poinsettia Rhizoctonia Stem Rot and Root Rot Lower stems develop dry, medium-dark brown surface lesions; roots may become brown and dried. See the Alabama Pest Management Handbook. Use Cleary's 3336 or Topsin M
Poinsettia Rhizopus Stem Rot Stem sections become glassy and water-soaked; a delicate black mass of fungal threads and small black spherical structures may develop over the lesions. Sanitation.
Poplar Anthracnose Brown, circular-irregular leaf spots which may follow along leaf veins. Sanitation of fallen leaves in the fall.
Rhododendron Cercospora Leaf Spot Relatively large (5-15 mm diam.) irregular, brown spots. Sanitation; use Cleary's 3336 or Topsin M or a WP benomyl (not Benlate).
Rhododendron Phytophthora Crown Rot Dark brown, wet decay at lower stem area. Sanitation; see Alabama Pest Management Handbook.
Rhododendron Pythium Crown Rot Dark brown, wet decay at lower stem area. Sanitation; see Alabama Pest Management Handbook.
Rose Cercospora Leaf Spot Brown angular leaf spots of variable size. Sanitation; see the Alabama Pest Management Handbook under black spot.
Willow Cercospora Leaf Spot Small circular, brown spots. Sanitation of leaves in the fall. See the Alabama Pest Management Handbook.
Willow Rust (Melampsora)> Rust-colored powdery spots that later become brown-colored. Sanitation of leaves in the fall


UPCOMING EVENTS

November 9, 2000:
North Alabama Nursery Field Day
Huntsville and Madison County Botanical Gardens
For more information contact Linda Van Dyke, ANA by phone at 334-821-5148 or Ken Tilt at 334-844-5484; or e-mail to alna@prodigy.net

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 alna@prodigy.net

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 psmeal@vt.edu

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: psmeal@vt.edu

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 mbippser@neca.com

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: dmorgan@bsipublishing.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.