How to differentiate Dutch elm disease from elm phloem necrosis.

Bibliographic Details
Corporate Author:	United States. Forest Service
Format:	Government Document Book
Language:	English
Published:	Broomall, PA : U.S. Dept. of Agriculture, Forest Service, 1981.
Series:	NA-FB/P ; 11.
Subjects:	Dutch elm disease > United States. Elm phloem necrosis.

Evans: US Documents (Annex 5th floor)