1. Scott Enebak Auburn University School of Forestry & Wildlife Sciences Important forest diseases in the southeastern United States

2. Tree Diseases Literally 1000’s of different tree diseases Only a problem when they interfere with human objectives –Pitch Canker –Annosus Root Rot –Fusiform Rust –Little Leaf Disease

3. –Brown Spot Needle Blight –Oak Wilt –Oak Decline –Dogwood Anthracnose –Hardwood Decay –Abiotic Disorders Tree Diseases

4. Signs & Symptoms Signs – The outward expression of the actual organism causing the disease –Conk, Mushroom, Spores, Bacterial slime, etc. Symptoms – An outward expression of the host that indicates that something is physiologically wrong with the tree –Decay, Canker, Resin flow, Swelling, Dead branch, Yellow foliage, etc.

5. Pitch Canker Fusarium subglutinans – native fungus Branch & stem dieback, deformity, growth reduction, tree mortality Slash, Loblolly, Shortleaf & Longleaf Pine Plantations, Natural Stands, Nurseries & Seed Orchards

6. Pitch Canker Wound pathogen Associated with overstocked stands, insect outbreaks & storm damaged trees

7. Pitch Canker Use appropriate species at appropriate densities – keep stand healthy & vigorous Do not add, or sparingly add Nitrogen to stand Plant disease-free seedlings from nurseries Use seed-tree (shelterwood) regeneration

8. Annosus Root Rot

9. Insert Fomes Movie Clip Here

10. Blue Pad – Example of Fomes Canker

11. Annosus Root Rot Heterobasidion annosum (Fomes annosus) Growth reduction, tree mortality All Southern Pines Associated with thinning and harvesting Soil factors influence stand risk Sandy, well-drained sites favor disease development Poorly-drained sites do not favor disease

12. Annosus Root Rot

13. Annosus Root Rot – High Risk Sites Reduce stocking levels (10' x 10') Avoid thinning as long as possible Prescribe burn stand prior to thinning Thin only during hot summer months Treat cut stumps with Borax Convert site to Longleaf pine

14. Annosus Root Rot - Medium Risk Reduce stocking levels (10' x 10') Reduce the number of thinnings Thin only during hot summer months Treat cut stumps with Borax

15. Cronartium quercuum f.sp. fusiforme Native disease – used to be obscure Forestry practices has increased incidence #1 Stem Disease in Southern US Stem deformation, growth reduction, tree mortality Slash, Loblolly, Shortleaf & Virginia pine Natural Stands & Plantations & Nurseries Fusiform Rust

16. Blue Pad – Example of Fusiform gall

17. Fusiform Rust

18. Use minimal amount of site preparation needed to get stand established Plant seedlings derived from genetically improved orchards - 2nd generation Plant disease-free seedlings Reduce alternate host using prescribed fires and/or herbicides Avoid addition of any fertilizer until at least age 8 Fusiform Rust

19. Phytophthora cinnamomii Growth reduction, stand stagnation & tree mortality Misidentified as a “beetle spot” Shortleaf, Loblolly & Slash pine Closely associated with soils that are: poorly-drained low in nutrients highly-eroded Little Leaf Disease

22. Blue Pad – Example of Increment Core of Tree

23. Avoid sites that favor the fungus high clay content poor internal drainage easily eroded Shorten stand rotation & objectives Add 400 lbs/ac 5-10-5 every 4 yr to get stand to rotation Convert stand to less susceptible host Little Leaf Disease

24. Mycosphaerella dearnessii Defoliation, growth reduction, seedling mortality Lengthens rotation and stand failure Longleaf Pine Brown Spot Needle Blight

26. Serious infections result in defoliation of seedling

27. Plant resistant seedlings eastern U.S. sources better than western U.S. Use prescribed fires prior to planting or seed-fall if using natural regeneration Use winter prescribed fire every three years until seedlings are out of grass stage Once out of grass stage disease is inconsequential Brown Spot Needle Blight

28. Oak Wilt Ceratocystis fagacerum Native disease of Quercus spp. (oaks) Fungus is moved around by insects that visit wounds Mostly human problem in United States Once into vascular system – the fungus moves rapidly from tree to tree via root grafts

29. Oak Wilt Range of oak wilt in the United States

30. Oak Wilt Aerial view of Oak Wilt infection center moving through oak forest

31. Oak Wilt – Kills red oaks fast! Pictures of same oak tree taken two weeks apart

32. Oak Wilt The fungus will produce “pressure pads” on some oak species Insects are attracted to the fruity odor the fungus emits Perfectly happy to stay and eat

33. Oak Wilt

34. Oak Wilt – Leaf symptoms Live Oak – Intervienal Chlorosis Red Oak – Marginal Necrosis

35. Oak Wilt DO NOT WOUND OAKS IN THE SPRING Reduce inoculum –Eliminate infected trees and firewood Stop below-ground spread –Break root grafts: vibratory plow, backhoe, trencher, chemicals (VAPAM) Intervascular injection of select trees –Systemic fungicides

36. Oak Decline Range of oak forest type and symptoms of decline

37. Oak Decline Oak mortality is from a relationship between the environment, a root decay fungus and an insect Fruiting bodies (conks) at base of tree and mycelia fan under the bark of Armillaria mellea

38. Oak Decline Two-lined chestnut borer attacks and girdles stressed trees Branch die-back and tree mortality occurs as the food and water is disrupted

39. Oak Decline Environment – drought, heat and cold cannot be “managed” Maintain general health of stand Proper spacing – planting, thinning Careful and proper harvesting practices Proper moisture if landscape trees

40. Hardwood Decay 100’s of fungal species decay wood Normal natural part of the ecosystem

41. Hardwood Decay Minimize wounding Remove infected trees –Reduces risk –Reduces inoculum –Increases value of stand

42. Insert Dogwood Movie Clip Here

43. Dogwood Anthracnose Discula destructiva - introduced fungus Causes leaf blight, twig and branch blight, stem cankers and tree mortality Most severe: –Higher elevations –North facing slopes –Areas near water

44. Dogwood Anthracnose Symptoms of fungal infection on leaf (flower) bracts, leaf and stem

45. Dogwood Anthracnose Symptoms of fungal infection on stem and tree mortality

46. Dogwood Anthracnose High Risk Areas – Dogwood is becoming scarce with 100% mortality Low Risk Areas – Dogwood can survive without human intervention Landscape Settings – 10 Things for growing Healthy Dogwoods Outlook - Some resistant material has been located but will take years to get back into natural settings

47. Abiotic Disorders - I High Temperatures –Sunscald (summer and winter) –Leaf scorch Low Temperatures –Frost injury –Frost crack –Winter burning / Winter drying

48. Abiotic Disorders - II Moisture Extremes –Drought –Flooding Chemical Imbalances –Nutrient deficiencies –Herbicide injury –Air Pollution –Salt injury