Bur Oak Blight in Minnesota Tree Care Advisor Core Course Training 2012
You’ve Prepared Your Community for…
Dutch Elm Disease
You’ve Prepared Your Community for…
Oak Wilt
You’ve Prepared Your Community For
Emerald Ash Borer
But…What About BOB? Prepare Your Community for Bur Oak Blight = BOB
Bur Oak Blight…the details
Fungal Foliar Disease (Leaf Spot) Tubakia species Bur Oak Specific
1. What Does it Look Like?
Note “wedge-shaped” symptomology
2. Is It In Minnesota? ď Ż ď Ż
Yes Confirmed in Hennepin, Mille Lacs and Sherburne Counties
3. What Trees Are Affected?
Only Bur Oak…to date
4. How Does It Spread?
4. How Does It Spread?
Spores from infected leaf blades and petioles Spring infection
5. Recognizable Symptoms?
Summer (July >) leaf spotting and blotching Leaves turn brown/gray Worse at bottom of crown and interior Many leaves retained through winter Worsens each year
6. Can Anything Be Done?
Baby Steps Maintain Health: Water Management, Mulch Chemical Injections: Propiconazole
7. For More Help and Information… For BOB testing: •Collect branch tips with symptomatic and healthy leaves from several locations on the tree; •Wrap them in dry paper toweling (no plastic bags, please), and send them to:
Plant Disease Clinic Department of Plant Pathology 495 Borlaug Hall 1991 Buford Circle St. Paul, MN 55108