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.