Anthracnose (fungus)	Leaflets are attacked early in the spring or fall. Dark-brown to black irregular lesions develop on the leaves. Yellowing and premature loss of leaves may result.	(Refer to the PDC Fact Sheet "Leaf Spot Diseases of Shade Trees and Ornamentals" for more information.) Application of nitrogen fertilizer to a young plantation (6 pounds nitrogen to 1,000 square feet) may help suppress infection and improve growth. Clean fallen leaves and prune dead branches. To be effective, fungicides must be applied before symptoms are seen. Sprays should begin at bud break and continue on a 10 to 14 day interval through the period of spring rains. Use azoxystrobin, chlorothalonil, chlorothalonil + fenarimol, copper products, mancozeb, maneb, myclobutanil, propiconazole, sulfur, thiophanate-methyl or triadimefon.
Fusarium canker (fungus)	Causes canker on trunk of walnut trees, usually within 2 feet of the soil. Secondary to ambrosia beetle attack. Seen mostly in plantation-grown trees, not in natural stands. Most of the cankers are annual, killing only bark tissue for one year.	None. Remove trees that are heavily damaged and destroy. Avoid damage to trees it may open them to infection. Beetles are attracted to stressed trees, so main tain trees in vigorous condition.
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	Email: plantclinic@missouri.edu