The History of Dutch Elm Disease in Grosse Pointe Park
Dutch Elm Disease (DED) is a fungus that is deadly to elm trees. It kills the tree by proliferating in the moist cambium just under the bark, clogging the porous xylem. This effectively "chokes" the tree by preventing water from traveling to the crown. Thus, a symptom of the disease is the yellowing and eventual falling of the leaves. It was unintentionally introduced from Europe in imported elm lumber around 1930. It was first diagnosed in Grosse Pointe Park in 1951. Today DED is present in much of the continental United States and is responsible for the death of over 80 million trees.
In 1951 Grosse Pointe Park had 4,007 city street trees that were American elm. This represented an overwhelming 80% of the street tree population. Casualties started slowly with only 6 loses that year. The city’s official year-end report optimistically stated that the “disease had been eradicated”. That declaration proved to be hauntingly inaccurate. Losses accelerated and peaked at 205 dead in 1982. For the past 2 decades losses fluctuated somewhat, averaging about 35 a year. We still have over 600 mature American elms on city easements in Grosse Pointe Park. For the past ten years we have actually been adding more than we’ve cut down by planting newly available disease-resistant varieties.
The graph above details elm losses annually. Interestingly, but not surprisingly, causalities spiked after DDT was banned in the mid 1970’s and again after spraying methoxychlor ceased in the early 1980’s.
The information above was provided by City Forester Brian Colter. If you have any questions, please contact Brian at firstname.lastname@example.org or at 313-822-6200.