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Name: Kerry
Grade: N/A
Location: N/A
Country: N/A
Date: N/A
Question:
I have Walnut Trees in my yard...they are giving off a sticky secretion that is covering decks, cars, ect. I just moved to this house last August and I do not remember this happening after I moved in...Is there just a period of the year that this secretion occurs from Walnut Trees?

Replies:
Possibly helpful:

http://www.coloradogardening.com/q&a_trees.htm

Walnut trees tend to ooze sap when pruned during the growing season, especially in summer. If it wasn't pruned, then the tree could have been injured and the sap is dripping.

Anthony Brach Ph.D.

Dear Kerry,

Please look carefully at the green, attached leaves of the tree. The sticky secretions could be from aphids sucking the sap from the veins of the leaves. The secretions are likely to be aphid honeydew or in the more vulgar vernacular "pooh".

Jim Tokuhisa, Ph.D.
Horticulture Department
Virginia Tech


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