OAK Decline Spreading Mid Atlantic and Southeast!
OAK Anthracnose (fungal) and OAK bacterial leaf scorch – Key POINTS!
Anthracnose is a fungal pathogen
o Typical in wet cool weather = Springtime disease
o Symptoms evident throughout growing season
o Symptoms include:
§
Scattered leaf canopy loss
§ Small brown spots and irregular dead areas with DISTORTED leaves – this is a key indicator
§ Not much leaf drop – dead leaves tend to stay on tree till late Autumn
Treatment Options
§ Increase the trees’ immune response
§ Supplemental water during dry/hot periods
§ Increase quality of soil environment
Oak Bacterial leaf scorch
o Causes are insects transmitting bacterium
o Symptoms appearing later in summer through fall – more severe in dry summers
§ Scattered yellowing and browning of leaf margins throughout canopy
§ Tip dieback with no leave at halo of canopy crown
§ Leaves remain attached through Autumn (not much leaf drop)
§ Starts as a scorching around the edges
§ Will sometimes see a yellow halo around the browning edge
o Can last 3 – 10 years
o Reported on Pin, white, and red oaks
pics include from Better Nature, Iowa State Extension, UMass, Missouri Botanical Gardens, and the Pacific Northwest Handbook.
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