FOR DISEASES OFTEN SEEN IN AUGUST
| PLANT | DISEASE | DESCRIPTION | CONTROL |
| AJUGA | Sclerotium rolfsii Crown Rot | Stems collapse at soil line; a white mold with brown mustard-seed sized sclerotia present. | Sanitation; solarization. |
| AUCUBA | Botryosphaeria Canker (Blotch) | Black, large irregular lesions on leaves and stems; dieback beyond cankers. | Sanitation; Cleary's 3336, Domain, or benomyl labelled for ornamentals. |
| AUCUBA | Helminthosporium Leaf Spot | Brown, elongate leaf lesion. | Sanitation; Cleary's 3336. |
| AZALEA | Phytophthora Crown/Root Rot | Crowns/roots become brown and wet or water-soaked. | See the APMH. |
| BEGONIA | Pythium Root Rot Rhizoctonia/Fusarium Lower Stem/Root Rot | Lower stem brown and decayed. | See the APMH. |
| CHRYSANTHEMUM | Bacterial Leaf Spot (Pseudomonas) | Dark brown/black, small (2-4 mm diam.), angular spots; sometimes with water-soaked edges. | Sanitation. |
| CHRYSANTHEMUM | Botrytis Blight | Brown spots, blotches. | See the APMH. |
| CHRYSANTHEMUM | Fusarium Wilt | Yellowing/wilt of leaves, beginning at the bottom of the plant and moving upward. | Sanitation; rotation for 7-10 years or solarization. |
| CHRYSANTHEMUM | Pythium Root Rot | Roots become brown and water-soaked. | Sanitation; protective fungicide drenches of Captan, Subdue, or Banol; solarization or crop rotation. |
| COLEUS | Phytophthora Crown Rot | Roots become brown and water-soaked. | Sanitation. |
| CRABAPPLE | Scab (Venturia) | Olive-brown circular, slightly raised spots (4-5 mm diam.) develop on leaves and fruit. | See APMH. |
| DAISY, GERBERA | Phytophthora Leaf Blight/Crown Rot | Leaves develop brown blotches; lower stem develop brown lesions; plants collapse. | See the APMH. |
| DAYLILY | Southern Blight (Sclerotium rolfsii) | A wet rot at soil line; sometimes a white fluffy mat of fungus at soil line. | Sanitation; solarization. |
| DOGWOOD | Cercospora Leaf Spot | Leaf spot on lower leaves of tree; angular to irregular leaf spots (2-6 mm) which are light brown or gray in the center and dark brown or purple on borders. | Sanitation. |
| DOGWOOD | Powdery Mildew (Phyllactinia) | Powdery white dusting on leaves; foliage distortion and death. | Sanitation in the fall; see APMH. |
| DOGWOOD | Septoria Leaf Spot | Leaf spots on lower leaves of tree; angular to irregular tan or brown spots (2-6 mm) sometimes with faint yellow halos. | Sanitation. |
| DOGWOOD | Spot Anthracnose | Tiny red spots on flowers and leaves. | Sanitation in fall; see APMH. |
| EUONYMUS | Anthracnose (Colletotrichum) | Small, whitish spots (1/16 in. diam.) on foliage. | Recommended fungicide sprays. See APMH. |
| FERN | Rhizoctonia Root Rot | Dark brown, dried,decayed roots. | Sanitation; see the APMH. |
| FORSYTHIA | Anthracnose | Brown, leaf spots/blotches. | Sanitation; see the APMH. |
| FORSYTHIA | Fusarium Crown Rot | Brown, dried, decayed lower stem. | Sanitation; crop rotation. |
| HOLLY, JAPANESE | Phytophthora Root Rot | Roots become brown and water-soaked; plants become yellowed with dieback. | See the APMH. |
| HOSTA | White Mold (Sclerotium rolfsii) | Lower trunk or stem is rotted and generally soft and limp. | Sanitation; possibly solarization. |
| HYDRANGEA | Cercospora Leaf Spot | Brown circular or angular leaf spots. | Sanitation; See APMH. |
| HYDRANGEA | Pythium Crown/Root Rot | Wet, water-soaked brown lesions on crown and roots. | See APMH. |
| IMPATIENS | Rhizoctonia Crown and Root Rot | Crown and roots become brown and dry rotted. | Sanitation; solarization may help. |
| IMPATIENS | Phytophthora Root Rot | Wet, water-soaked brown lesions on roots. | See APMH. |
| IVY, ENGLISH | Colletotrichum Leaf Spot | Brown leaf spots that are circular or irregular. | See the APMH. |
| IVY, ENGLISH | Phomopsis Canker | Brown, gray lesions on stems; dieback. | Sanitation; Cleary's or benomyl protective sprays. |
| IVY, ENGLISH | Phytophthora Root Rot | Roots become brown and water-soaked. | See the APMH. |
| JUNIPER | Phytophthora Root Rot | See Holly, Japanese. | See Holly, Japanese. |
| JUNIPER | Pestalotiopsis Needle Blight | Needles turn brown in patchy areas on branches. | Sanitation. See APMH; avoid stress. |
| MAPLE | Anthracnose (Kabatiella) | Small-large brown blotches develop on leaves, often folllowing along veins and/or leaf edges. | See the APMH. |
| MAPLE | Phyllosticta Leaf Spot | Small (4-8 mm diam.) leaf spots develop with brown-purple borders and brown-cream centers. | See the APMH, under 'Leaf Spot'. |
| SUGAR, MAPLE | Monastichella hysteroidea Leaf Spot | Brown irregular spots. | Sanitation. |
| MARIGOLD | Alternaria Leaf Spot | Black irregular spots 0.5-2 mm diameter. When spots are numerous, plant death may result. | See APMH, under 'Leaf Spot'. |
| MONDOGRASS | Anthracnose (Colletotrichum) | Gray, brown spots on leaves. | Sanitation. See APMH. |
| OAK | Anthracnose(Apiognomonia) | Small to large brown blotches develop on leaves, often following along veins and/or leaf edges. | Sanitation; See APMH for small oak trees. |
| OAK | Bacterial Scorch Disease (Xylella) | Leaf edge turns brown in scatttered locations in tree; gradual dieback over 2-3 years). | --- |
| OAK | Oak Leaf Blister (Taphrina) | Light brown leaf spots that are circular and concave-convex. | Sanitation. See the APMH. |
| PANSY | Pythium Root Rot | Roots become brown and water-soaked; plants become yellowed and finally die. | See the APMH. |
| PERIWINKLE | Anthracnose (Colletotrichum) | Brown, sunken cankers on stem sections. | Cleary's 3336, Domain, or WP benomyl; Sanitation. |
| PERIWINKLE | Phomopsis Blight | Brown, sunken cankers on stem sections. | Sanitation; Cleary's 3336, Domain or benomyl WP labelled for ornamentals. |
| PERIWINKLE | Phytophthora Aerial Blight | Dark brown lesions appear on stems; dieback. | Sanitation; Aliette. |
| PERIWINKLE | Phytophthora Root Rot | Roots become dark brown, decayed and water-soaked; foliage shows yellowing/dieback. | Sanitation; solarization. |
| PERIWINKLE | Rhizoctonia Aerial Blight | Lower stems and leaves become browned and dry-rotted. Some mycelial webbing may occur. Whole plants will eventually die. | Sanitation. Protective sprays of Cleary's 3336, Domain, or a benomyl WP labelled for ornamentals. |
| PERIWINKLE | Rhizoctonia/Fusarium Crown Root Rot | Dried, brown lesions on lower stem and roots. | Cleary's drenches will help provide some protection. |
| PINE, VIRGINIA | Fusarium Pitch Canker | Sunken lesions that ooze sap. | Sanitation. |
| PINE, VIRGINIA | Lophodermium (Ploioderma) Needle Cast | Last year's needles become spotted and browned; eventually they drop. Needles have tiny football-shaped, hard black bodies scattered over their surfaces. | See the APMH. |
| PINE, VIRGINIA | Rhizosphaeria Needle, Twig Blight (Suspect Stress Related) | Needles and twigs become brown and dead. | Apply Bravo 720 at rate of 5 1/2 pints per 100 gallons or Bravo 500 at 8 pts. per 100 gallons after shearing when growth is 1/2 inch and again when new growth is 2 inches long.. |
| POINSETTIA | Bacterial Stem Rot (Erwinia) | Lower stem becomes blackened and rotted; usually occurs on small plants. | Sanitation. |
| POINSETTIA | Pythium Root Rot | Roots water-soaked, decayed. | Sanitation; protective drenches fungicide; see APMH. |
| POPLAR | Alternaria Leaf Spot | Brown, irregular spots (8-15 mm diam.) develop on leaves. | Sanitation. Chemical treatment not usually recommended. |
| RED CEDAR | Phomopsis Blight | Tips of branches become brown with damage spreading into the lower sections of the branches. | See the APMH. |
| ROSE | Aerial Blight (Rhizoctonia) | Brown, irregular blotches on leaves. | Sanitation; Cleary's 3336 would give protective control. |
| VINCA MINOR | Alternaria Leaf Spot | Dark brown angular leaf spots; leaf blight. | Sanitation. Chipco 26019. |
| VINCA MINOR | Rhizoctonia Aerial Blight | Leaves or stems become blighted, spotted. | Sanitation; Cleary's or benomyl protective treatments. |
| WISTERIA | Phomopsis Stem Blight | Dieback and brown, dried sunken lesions. | Sanitation; Cleary's 3336. |
  
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Send horticultural questions to ktilt@acesag.auburn.edu.