CHICAGO (CBS) — Chicago area trees have been losing leaves early because of a cool wet spring and early summer, reports WBBM’s John Cody.

Plant Specialist Doris Taylor at the Morton Arboretum says the region received about seven inches of rain for May and five for June, compared with an average of three inches a month.

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“A lot of fungal diseases will occur in cool, wet weather,” said Taylor.

She says the result is a lot of tree leaves already on the ground.

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“Sycamore have been really heavily hit this year. We are seeing it on maples, we are seeing it on oaks,” said Taylor.

According to Taylor, the anthracnose fungus is causing tree leaf drop. She says it will not kill the tree and most leaves remain on. Those that fall may be still totally green, or green with spots or brown.

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Taylor says the best way to avoid the problem next year is to rake up the leaves and throw them away instead of composting them at home.