It is a very busy month for Ken. He has been traveling and is about to leave for the Southern Region International Plant Propagators Society meeting in Virginia. He'll be back here for a few days and then leaves for China. I suppose I am just getting you trusty readers ready for the fact that the next newsletter may be somewhat slim as he will be gone and I am busy working on a trio of grants. Thank you for checking us out every month - even a slim month can contain important information.
Enjoy the glorious fall days.
The following articles are featured in this month's Something to Grow On:
WHITE-TAILED DEER FEEDING PREFERENCE FOR SELECTED AZALEA CULTIVARS
NORTH ALABAMA NURSERY FIELD DAY
MAGNOLIA SOCIETY CONFERENCE AND TOUR OF IRELAND
HOST PLANTS OF JAPANESE BEETLES
MONTHLY PLANT PATHOLOGY REPORT
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.
WHITE-TAILED DEER FEEDING PREFERENCE FOR SELECTED AZALEA CULTIVARS
Student Research from recent SNA meeting in Atlanta, GA Christine Harris, Eric Simonne, Charles Gilliam, John Olive, Joseph Eakes, and Brian Bilich
Alabama is the largest azalea producer in the world. Not only are azaleas economically important for Alabama growers, but also to the entire nursery and landscape industry.
Azaleas have been shown to be palatable to white-tailed deer and feeding damage is responsible for crop losses and subsequent losses of profit as well. Strategies to control feeding damage include physical barriers, scare tactics, harvesting, and chemical control; however, no single strategy has been shown to provide complete protection. Several formulations have been developed and tested to reduce feeding damage to high value plants by decreasing their palatability. Putrescent egg solids are used in several products such as Big Game Repellent® and Deer Away.®
Although deer repellent and preference studies have been performed on woody species such as Japanese yew, apple, flowering dogwood, and Douglas fir, little information is available for ornamental crops such as azalea. The objectives of this study were to evaluate azalea cultivar preference and the efficacy of putrescent egg solids as a deer feeding control.
Azalea cultivars selected for this test were categorized as mid-season blooming and included Girard hybrids ' Hot Shot', 'Scarlet', and 'Christina Marie'; Krume hybrids 'Hino Crimson', 'Delaware Valley', and 'Massasiot'; and Southern Indica hybrids 'Red Formosa' and 'Mrs. G. G. Gerbing'.
Testing was conducted with 14 white-tailed deer confined in two one-acre enclosures. Ten replications of each cultivar were placed randomly within each pen. Five replications were treated with a putrescent egg-based deer repellent spray. The other plants were left untreated. Feeding damage was assessed daily on each plant.
Significant differences among feeding damage of azalea cultivars were found for both treated and untreated plants. In one deer pen only 'Massasiot' and 'Scarlet' were not completely eaten within the first four days of the test. By day 5, however, all control plants were completely destroyed. The use of putrescent egg-based spray was shown to reduce deer feeding on azalea. In another pen, 'Mrs. G. G. Gerbing' was not completely destroyed by day 8. In fact, all other cultivars were damaged to 100% by day 4. However, 'Mrs. G. G. Gerbing' did sustain 80% damage by day 4. Only day 8 demonstrated 100% destruction of all treated plants in one deer pen. Half of the cultivars sustained 80% or less foliar damage after one week of exposure.
Although performed under extremely high deer feeding pressure, significant deer feeding preferences were found among azalea cultivars. However, choosing an azalea cultivar based on deer palatability may not always satisfy the consumer's wishes. It is important to consider the use of deer repellent products such as putrescent egg spray in combination with careful cultivar selection in areas where deer pose a threat to nursery or landscape settings
NORTH ALABAMA 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:
Registration and Coffee Talk
Weed Control in the Field
Dr. Charles Gilliam
Making Your Herbicides Live Up to Their Name and Banding With Rigged Sprayers Designed for Nurseries
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
10:15 – 11:15
The Nursery Production System: Putting It All Together
Dr. Ken Tilt
11:15 – 11:45
North Alabama Horticulture Treasure: Quick Highlight Tour of the Gardens
Director of Huntsville Botanical Gardens and Secretary-Treasurer of the Alabama Nurserymen's Association
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
Alabama Nurserymen's Association
P.O. Box 9
Auburn, AL 36831-0009
Department of Horticulture
101 Funchess Hall
Auburn University, AL 36849
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
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.
If you are looking for a wonderful way to spend 10 days in the spring (March 20 - March 30, 2001) you may want to consider the Magnolia Society Conference and Tour of Ireland. The tour will link the scenic beauty of the country with the tremendous wealth of plants that can be grown under the influences of a termperate maritime climate. Tour participants will visit a fascinating variety of gardens and stay in historic first class hotels. For more information write to:
MAGNOLIA SOCIETY TOUR AND CONFERENCE
RHS Garden Wisley
HOST PLANTS OF JAPANESE BEETLES
by Kathy Flanders, Extension Entomologist, Auburn University
Now that we have some rain, I am starting to think about replacing the landscape plants that fell victim to the drought.
I am not the only one who should think about choosing landscape plants that are resistant to feeding by Japanese beetle adults. I don't have Japanese beetles in my backyard yet. But I know it is just a matter of time, as they occur in other parts of Auburn. They are well established in Tuscaloosa and Walker Counties, and the northeastern part of the state. Scattered infestations occur elsewhere in Alabama.
The grubs of Japanese beetles feed on grass roots, and are pests of turfgrass and certain pasture grasses. However, if you have Japanese beetles in your county, you know that the adults are the most annoying stage of this pest. They feed on many of our favorite landscape plants, including crape myrtle, Japanese maple, sycamore, roses, apples, apricots, cherries, plums and grapes. Looking on the bright side, Japanese beetle adults are very fond of poison ivy!
The following plants were cited in a 1972 USDA Technical Bulletin, Biology of the Japanese Beetle, as "having no record of beetle feeding on plant". (If you would like a copy of the entire list please send us an email and we'll be happy to mail it to you).
Acer rubrum - Red maple
Acer saccharinum - Silver maple
Celosia argentea cristata - Cockscomb
Vinca minor - Ground myrtle
Ilex aquifolium - English holly
Ilex cornuta - Chinese holly
Ilex crenata - Japanese holly
Ilex opaca - American holly
Impatiens balsamina - Garden balsam
Begonia rex-cultorum - Begonia
Myosotis sylvatica - Forget-me-not
Buxus sempervirens - Boxwood
Pachysandra terminalis - Japanese spurge
Calycanthus floridus - Carolina allspice
Lonicera fragrantissima - Winter honeysuckle
Symphoricarpos albus - Snowberry
Symphoricarpos orbiculatus - coralberry
Dianthus barbatus - Sweet william
Dianthus caryophyllus - Carnation
Gypsophila paniculata - Baby breath
Gypsophila repens - Creeping gyposophila
Stellaria media - Common chickweed
Celastrus scandens - American bittersweet
Eunonymus alatus - Winged euonymus
Euonymus fortunei - Climbing euonymus
Tradescantia fluminensis - Wandering-Jew
Ageratum conyzoides - Ageratum
Caladium bicolor - Caladium
Centaurea cineraria - Dusty miller
Centaurea cyanus - Cornflower
Centaurea montana - Mountain-bluet
Coreopsis lanceolata - Lance coreopsis
Rudbeckia hirta - Brown-eyed susan
Rudbeckia lacinata - Coneflower
Rudbeckia laciniata hortensis - Goldenglow
Cornus florida - Flowering dogwood
Sedum spectabile - Showy sedum
Chamaecyparis lawsoniana - Lawson white cedar
Chamaecyparis obtusa - Hinoki cypress
Chamaecyparis pisifera - Sawara cypress
Chamaecyparis thyoides - Atlantic white cedar
Kalmia latifolia - Mountain laurel
Rhododendron nudiflorum - Pinxterbloom azalea
Dicentra formosa - Pacific bleedingheart
Bambusa vulgaris - Common bamboo
Dactylis glomerata - Orchardgrass
Hedeoma pulegioides - American pennyroyal
Hyssops officinalis - Hyssop
Mentha spicata - Spearmint
Physostegia virginiana - False dragonhead
Albizzia julibrissin - Mimosa
Baptisia australis - Blue false-indigo
Cercis chinensis - Chinese redbud
Lathyrus odoratus - Sweetpea
Convallaria majalis - Lily of the valley
Erythronium albidum - Dogtooth violet
Lilium longiflorum - Easter lily
Lilium speciosum - Showy lily
Lilium tigrinum - Tiger lily
Yucca flamentosa - Adam's needle yucca
Liriodendron tulipifera - Tulip tree
Magnolia grandiflora - Southern magnolia
Magnolia soulangeana - Saucer magnolia
Magnolia virginiana - Laurel magnolia
Nymphaea odorata - American waterlily
Forsythia intermedia - Border forsythia
Forsythia suspensa - Weeping forsythia
Fraxinus americana - White ash
Fraxinus pennsylvanica - Red ash
Syringa persica - Persian lilac
Syringa vulgaris - Common lilac
Papaver nudicaule - Iceland poppy
Papaver orientale - Oriental poppy
Phytolacca americana - Common pokeberry
Abies concolor - Balsam fir
Picea abies - Norway spruce
Picea orientalis - Oriental spruce
Pinus sylvestris - Scotch pine
Pseudotsuga taxifolia - Douglas fir
Tsuga canadensis - Hemlock
Portulaca grandiflora - Common portulaca
Aquilegia canadensis - American columbine
Aquilegia vulgaris - European columbine
Clematis heracleaefolia - Tube clematis
Delphinium formosum - Hardy larkspur
Helleborus niger - Christmas rose
Ranunculus acris - Meadow buttercup
Ranunculus sceleratus - Bitter buttercup
Reseda odorata - Common mignonette
Populus alba - White poplar
Populus alba pyramidalis - Bolleana poplar
Heuchera sanguinea - coralbells
Hydrangea arborescens - Smooth hydrangea
Hydrangea paniculata - Panicle hydrangea
Philadelphus coronarius - Mock orange
Ribes grossularia - European gooseberry
Ribes oxyacanthoides - Northern gooseberry
Antirrhinum majus - Snapdragon
Chelone glabra - White turtlehead
Digitalis purpurea - Foxglove
Verbascum thapsus - Mullein
Vernonica officinalis - Speedwell
Staphylea trifolia - American bladdernut
Taxus baccata - English yew
Taxus canadensis - Canada yew
Taxus cuspidata - Japanese yew
Tropaeolum majus - Garden nasturtium
Callicarpa dichotoma - Beautyberry
Lantana camara - Lantana
Viola odorata - Sweet violet
Viola papilionacea - Butterfly violet
Viola tricolor - Pansy
PLANT PATHOLOGY REPORT
AUGUST PLANT PROBLEM REPORT FROM THE AUBURN AND BIRMINGHAM PLANT DIAGNOSTIC LABS WITH DISEASE POSSIBILITIES FOR SEPTEMBER
Auburn Plant Disease Report for August
Jackie Mullen, Extension Plant Pathologist and Diagnostician, Auburn University
As we all know, the summer-time drought extended through August for most areas of the state. Many of the samples received this past August were environmental stress problems. Of the diseases seen, most were from landscape and turf grass situations.
Pythium and Phytophthora root rots and stem blights were observed in those situations where irrigation was ample or above ample and/or where soil water drainage may be poor. Pythium is a serious disease agent with herbaceous plants. On chrysanthemum, Pythium will cause a serious stem and root rot. Pythium blights are often a common and serious problem on cool-season turf grasses. We also saw the problem on golf course bentgrass. Pythium is often a secondary decay agent of woody ornamental roots. It causes root decay after the roots had been injured, stressed, or damaged by a previous problem or disease. But, Pythium may cause a primary decay of feeder roots of woody plants in some wet situations. Phytophthora, a fungus closely related to Pythium, is known to be an aggressive pathogen of woody ornamentals and herbaceous plants. It is often found as a crown or root rotter, but sometimes it causes foliage diseases. The boxwood and pittosporum crown & root rot diseases were typical Phytophthora diseases. The Phytophthora stem blight of periwinkle is the most common and serious disease problem on periwinkle in Alabama and many other areas. Disease control for Pythium and Phytophthora diseases is usually similar. Damaged plants usually should be removed. The water situation in the area should be modified so that the area is less wet. Depending upon the situation, protective fungicide drenches may be needed. This is often the case in nursery/greenhouse areas.
Hypoxylon canker of oak has been noted in more than one situation this summer. The fungus will infect other trees as well, but it is most commonly seen on oaks, especially stressed oaks. Infections often begin by wind-blown spores landing upon wounds or breaks in the bark surface. The fungus develops below the bark and eventually a dark gray or black, hard fungal mat (or stroma) develops just below the bark. Infected trees will eventually show dieback symptoms. When the disease occurs on the main tree trunk, little can be done to remove the fungus from the tree. Tree removal is often recommended so as to prevent continued spread of the disease.
A bacterial leaf spot of Indian hawthorn has recently been diagnosed. The spots are dark red, small (usually 1-2 mm), and angular. With recent infections, the leaf spot edges appear water-soaked on lower leaf surfaces. The specific bacteria has not been identified as yet.
2000 August Plant Diseases Seen In the Plant Diagnostic Lab At Auburn.
Bermuda Take-all Patch (Gaeumannomyces) Elmore Boxwood Phytophthora & Pythium Root Rot Boxwood Volutella Blight Chrysanthemum Pythium Stem Rot, Root Rot Cypress, Leyland Cercospora Blight Dogwood Cercospora or Septoria Leaf Spot Cullman Dogwood Phyllosticta Leaf Spot Talladega Hydrangea Colletotrichum Blossom Blight Choctaw Indian Hawthorn Bacterial Leaf Spot Escambia Iris Anthracnose (Stem) (Colletotrichum) Russell Iris Fusarium Bulb Rot Russell Oak Hypoxylon Canker Lauderdale Pear, Bradford Fabraea Leaf Spot Russell Pear, Bradford Fireblight (Erwinia amylovora) Houston Periwinkle Phytophthora Stem Blight Tuscaloosa Pittosporium Phytophthora & Pythium Root Rot Coffee Locations are not reported for nursery and greenhouse samples.
Birmingham Plant Disease Report for August
Jim Jacobi, Extension Plant Pathology Specialist, Birmingham
The lack of rainfall this summer was one of the main causes and contributing factors in the plants received during August. Nearly 50% of the plants received last month had problems related to the drought conditions. The reported rainfall totals were from 2.21 inches at the Birmingham International Airport to 0.43 inches and lower at other local reporting stations. Most of the diseases were either soilborne or related to the dry weather. The hot dry weather also caused poor pollination and pod death in okra. This was also reported in other areas in Alabama this summer.
As we enter into September and October (historically two of our driest months), keep watering important trees and shrubs.
2000 August Disease Seen In The Birmingham Plant Diagnostic Lab
Azalea Phomopsis Dieback Jefferson (2) Boxwood Volutella Blight/Stress Jefferson(3) Cherry, Weeping Higan Shot Hole (Xanthomonas spp.) Jefferson Cypress, Leyland Seridium Canker Jefferson Dianthus Pythium Root Rot Jefferson Daphne, Winter Fungal Dieback Jefferson Dogwood Leaf Scorch Jefferson Holly, Dwarf Yaupon Pythium Root Rot Jefferson Hydrangea, Oak Leaf Armillaria Root Rot Shelby Ivy, English Scale Jefferson Juniper Phomopsis Tip Blight Jefferson Liatris (Blazing Star) Southern Blight Jefferson Pine, Loblolly Southern Pine Beetle Tallapoosa Poinsettia Pythium Root Rot . Rose Black Spot Jefferson Smoketree Powdery Mildew Jefferson
Disease Possibilities For SeptemberAugust continued to be dry in most areas, but rainy weather developed the first week of September. Evidence of bacterial scorch disease may occur in September. Scorch disease, caused by the bacteria Xylella, causes leaf edge scorch and dieback of elm, oaks (red and black oaks including northern red, pin, scarlet, southern red, laurel, shingle, and water oaks), sycamore, mulberry, and red maple. Symptoms of scorch may first occur in mid-late June, but disease is often not noticed until late summer or early fall when symptoms are more pronounced. Generally, leaf symptoms progress from older to younger leaves, with leaves at branch tips often showing no symptoms. Scorched leaves curl upward and remain attached. Infected trees develop a progressive dieback and general (usually slow, over many years) decline. Scorch can be confirmed with an ELISA test. Many fungal leaf spot diseases will develop on pre-senescent shade tree foliage in September. Generally these spots are of no concern. It is, however, always a good idea to remove fallen spotted foliage from the area later this fall or winter.
DISEASE DESCRIPTIONS AND BRIEF CONTROL COMMMENTS ON
SOME COMMON DISEASES OFTEN SEEN IN SEPTEMBER
PLANT DISEASE DESCRIPTION CONTROL Aucuba Lasiodiplodia Canker Black sunken spots or sunken areas on aucuba stems. Dieback of foliage results. Cleary's 3336, or Domain protective sprays labelled for ornamentals; sanitation. Azalea Cercospora Leaf Spot Small dark brown-black, usually circular spots (1-2 mm) scattered over leaf surface. Sanitation and Cleary's 3336 protective sprays. Azalea Phytophthora Crown and Root Rot Lower stem near soil and roots become brown and water-soaked. Sanitation and proper soil or potting mix drainage are important. See Alabama Pest Management Handbook and/or ANR-571. Azalea Rhizoctonia Aerial Blight Brown, irregular spots and lesions begin on lower leaves. Whole leaves may become blighted; leaf drop occurs. Sanitation; See Alabama Pest Management Handbook. Begonia Phytophthora Crown Rot Crown tissues are dark and wet-rotted. Sanitation. Reduce watering. Begonia Phytophthora & Pythium RootRot Roots become brown and water-soaked, decayed. Sanitation. Reduce watering. See the Alabama Pest Management Handbook. Begonia Rhizoctonia Root Rot Brown, dry, decayed roots. Sanitation. Banrot protective drenches. Begonia Root-Knot Nematode (Meloidogyne) Galls on roots; plants stunted and wilted. Solarization. Begonia Tomato Spotted Wilt Virus Yellow mosaic and ring spots present. Sometimes brown spots also present. Thrips control. Sanitation. Boxwood Phytophthora Root Rot Brown, water-soaked roots. See Alabama Pest Management Handbook. Celosia Phytophthora, Pythium, Fusarium Lower Stem Rot & Root Rot Roots brown and decayed. Sanitation. Reduce watering. Improve soil drainage. Cherry Septoria Leaf Spot Small (0.5 cm or less in diam.), angular brown spots. Sanitation in the fall. Cleyera Phytophthora Root Rot See Boxwood. Sanitation. Improve soil drainage. Cypress, Leyland Cercospora (Cercosporella) Blight Needle and twig blight that usually begins on lower foliage. Sanitation. Cleary's 3336 protective sprays. Dogwood Botryosphaeria Canker Slightly sunken lesion, sometimes with cracks along the margin. Sanitation. Dogwood Cercospora Leaf Spot Angular-irregular tan-brown lesions (2-6 mm diam.) sometimes with a thin yellow halo. Usually sanitation is the only control measure needed. Dogwood Septoria Leaf Spot Angular, brown spots, about 1 cm or less in diam; may be confused with Cercospora leaf spot. Collect and remove fallen leaves this fall. Dusty Miller Alternaria Leaf Spot Dark, angular spots. Sanitation; Cleary's 3336. Eleagnus Phytophthora Root Rot Brown, wet root decay. Sanitation. Improve soil drainage. Euonymus Anthracnose (Colletotrichum) Small brown spots (about 5 mm or smaller) on foliage. Sanitation; See the Alabama Pest Management Handbook for protective fungicide recommendations. Fern Anthracnose (Colletotrichum) Gray-brown irregular blotches on fronds. Orange spore masses may be present in humid weather. Sanitation; See the Alabama Pest Management Handbook under leaf spot. Fern Rhizoctonia Aerial Blight Gray or brown irregular blotches on fronds; some 'shot-hole'. Sanitation; See the Alabama Pest Management Handbook. Gardenia Phytophthora Crown Rot Lower stem/trunk at the soil line develops wet decay. Sanitation. (See the Alabama Pest Management Handbook under Root Rot for protective treatment.) Hickory Scab (Cladosporium) Small, dark brown, slightly raised leaf spots. Sanitation in the fall. Holly, Blue Maid Botryosphaeria Canker Brown or black sunken, cracked lesions (cankers) on branches. Sanitation. Protective sprays of Cleary's 3336, Domain or a WP benomyl labelled for ornamentals. Holly, Blue Maid Phytophthora Root Rot Feeder roots become water-soaked, decayed. See the Alabama Pest Management Handbook. Hydrangea Cercospora Leaf Spot Relatively large (0.5-1.0 cm) dark brown circular spots with reddish borders. Sanitation. See the Alabama Pest Management Handbook. Hydrangea Phytophthora & Pythium Root Rot Roots become brown and water-soaked. Sanitation. See the Alabama Pest Management Handbook. Impatiens Alternaria Leaf Spot Small circular or angular dark brown spots. Sanitation; a mancozeb product such as Duosan or Zyban. Iris Bacterial Soft Rot Soft, wet, watery rot of rhizome. Sanitation. Control insect problems. Iris Fusarium Rhizome Rot Areas of the rhizome exhibit a dry, brown rot. Sanitation. See the Alabama Pest Management Handbook. Ivy, English Phytophthora Crown & Root Rot Tissues dark and water-soaked. Sanitation; reduce irrigation or improve drainage. Juniper Phomopsis Dieback Juniper branch tips become brown. Cankers develop on twigs and dieback continues down the twig. See the Alabama Pest Management Handbook. Juniper Phytophthora Root Rot See Holly. . Ligustrum Cercospora Leaf Spot Brown irregular spots (about 1 cm diam.) on foliage; when leaf spot is severe, defoliation may result. Sanitation; See the Alabama Pest Management Handbook. Liriope Anthracnose (Colletotrichum) Brown irregular blotches on leaf blades; often, leaf tip areas are involved. Sanitation; See the Alabama Pest Management Handbook. Loripetalum Pythium Root Rot Light brown, water-soaked, rotted roots. Sanitation. Reduce irrigation or improve soil drainage. Maple Anthracnose (Kabatiella) Brown spots and blotches on foliage; enlarged spots may involve more than half of individual leaves. Sanitation. See the Alabama Pest Management Handbook. Maple Phyllosticta Leaf Spot Gray circular spots (¼ inch diam., approx.) with dark brown or reddish brown borders. Sanitation. Marigold Alternaria Leaf Spot Small (0.2-0.3 cm diam.) dark brown-black spots. Numerous spots cause death of plants. Sanitation. See the Alabama Pest Management Handbook. Oak Powdery Mildew (Microsphaera) White dusty coating on upper leaf surfaces. Some distortion of new leaves. Collect and remove fallen leaves this fall. Oak, Pin Xylella Scorch Lower and oldest leaves show leaf edge scorch; problem progresses upward through the tree canopy. Dieback develops; eventual tree death. Remove dying trees. Pansy Anthracnose (Colletotrichum) Small, round, light brown, cream-colored spots. Sanitation. Cleary's 3336. Pansy Myrothecium Crown Rot Dieback; decayed crowns. Sanitation; See A. Hagan. Pansy Phytophthora & Pythium Root Rot Brown, wet-rotted roots. Sanitation. See Alabama Pest Management Handbook. Pansy Phyllosticta Leaf Spot Relatively small (2-3 mm diam.) medium brown, roughly circular spots. Spot centers may become gray. Sanitation. Protective sprays of Cleary's 3336, Domain, or a benomyl WP labelled for ornamentals. Pansy Phytophthora Root Rot Roots become brown and water-soaked. Sanitation. See the Alabama Pest Management Handbook. Pansy Pythium Root Rot Roots become brown and water-soaked. Sanitation; See the Alabama Pest Management Handbook. Pansy Thielaviopsis Root Rot Roots become covered with black spots/ lesions. Sanitation; Cleary's, or Domain protective drenches. Pear, Bradford Fabraea Leaf Spot Black circular spots (about 0.2-0.4 cm diam.) Sanitation of fallen leaves in the fall. Regular spray schedule may help. Petunia Phytophthora Root Rot Roots water-soaked, decayed. Sanitation Photinia Armillaria Root Rot Plant may decline slowly or suddenly; lower trunk under the bark and roots may be covered with closely appressed white fungal mat with black, threadlike structures. Sanitation. See PP-145. Photinia Phytophthora Root Rot See Azalea. . 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 brown needles. Protective fungicides spray. See Alabama Pest Management Handbook. Pine, Virginia Rhizosphaeria Needle Cast Needles become gray-brown. Twig blight may develop. Sanitation. See the Alabama Pest Management Handbook. Pittosporum Southern Blight (Sclerotium rolfsii) Lower trunk becomes rotted and softened. White mycelial mats and tiny black spherical bodies (sclerotia) may be present on trunk at soil surface. Sanitation. Poinsettia Rhizoctonia Stem Rot & Root Rot Lower stems develops dry medium-dark brown surface lesions; roots may become brown and dried. See Alabama Pest Management Handbook. Poinsettia Pythium Root Rot Roots become medium brown, soft, water-soaked and rotted. See Alabama Pest Management Handbook. 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. Poinsettia Bacterial (Erwinia) Stem Rot Black, water-soaked spots or lesions on stems. Lesions may girdle stems. Sanitation; pot-level irrigation; See Alabama Pest Management Handbook. Red Cedar Phomopsis Tip Blight Tips of twigs become yellowed and browned. Dieback may spread down the twig-branch. Lower foliage is affected first. Sanitation. See the Alabama Pest Management Handbook. Rose Phytophthora Root Rot Dieback; active infections are wet-rotted; old infections are dried. Sanitation; reduce watering. Schip Laurel Bacterial Leaf Spot (Xanthomonas) Angular brown spots with water-soaked margins; shot-holes develop. Sanitation. . Snapdragon Cercospora Leaf Spot Pale brown angular leaf spots of variable size. Cleary's 3336, Domain, or a benomyl labelled for ornamentals Thrift Rhizoctonia Blight Stem and leaf browning. Sanitation; Cleary's 3336. Verbena Anthracnose (Colletotrichum) Circular black spots on foliage. Sanitation; Cleary's 3336. Verbena Pythium Lower Stem Rot Brown water-soaked lesions. Sanitation; reduce irrigation. Vinca (Periwinkle) Anthracnose (Colletotrichum) Brown irregular areas, blotches develop on leaves and stems. Sanitation. Protective sprays of Cleary's or Domain or a WP benomyl labelled on ornamentals may help. Vinca (Periwinkle) Phytophthora Stem Rot and/or Crown/Root Rot Stems and/or lower stems near soil line and roots become browned and water-soaked. Sanitation; improve soil drainage. Vinca(Periwinkle) Pythium Root Rot Roots become brown decayed and water-soaked. Sanitation. Reduce watering schedule. Rotate to different crop. Vinca(Periwinkle) Rhizoctonia Aerial Blight Lower leaves become blighted; a thin mycelial webbing may develop. Sanitation; Cleary's, Domain or a WP benomyl labelled on ornamentals may help. Wax Myrtle Anthracnose (Colletotrichum) Brown, irregular spots, blotches develop on leaves. Sanitation; if disease is severe, protective sprays of Cleary's 3336 or Domain or a WP benomyl may help. Wax Myrtle Gummy Stem Blight (Mycosphaerella) Black lesions/spots at leaf edges; elongate cracking on stem with amber-colored ooze. See Alabama Pest Management Handbook.
UPCOMING EVENTSOctober 8-11, 2000:
Southern Region International Plant Propagators' Society.
Norfolk, VA. Contact David Morgan at 817-882-4148; fax 817-882-4121, SR IPPS, P.O. Box 1868, Ft. Worth, TX 76101; 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 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: firstname.lastname@example.org
Send horticultural questions and comments to email@example.com.
Send questions and comments to firstname.lastname@example.org.
Letters to Bernice Fischman - 101 Funchess Hall - Auburn University, AL 36849.