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Entomology (Study of Bugs)/Bug/Larvae inside Ash Tree


Recently the storms in Minneapolis brought down a tree in a friends front yard. The ash tree was around 50 years old from neighbors accounts and in good condition. When cutting the tree up into movable pieces we encountered pockets with what looked to be black pupas with larvae inside. The larvae were white with a reddish brown head and were 1/4" to 3/8" thick and about a inch long. I assume this was a stag beetle since it was late May early June. Any Thoughts as to what it was. EAB is not a possibility as we looked at that first.




Without seeing at least an image, it is extremely difficult to reach any kind of conclusion.  LOTS of beetles attack rotting wood.  Stag beetles are a possibility.  So are "bess beetles," family Passalidae, or scarabs, including the subfamily Dynastinae.  The larvae you found were "prepupae" inside a cell made of wood fibers, sawdust, saliva of the larva, and other material.


Entomology (Study of Bugs)

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Eric R. Eaton


I answer insect and spider identification questions ONLY. Attach images if possible. No "what bit me?", "what do I feed this bug in captivity?", or science fair project questions please. NO TECHNICAL QUESTIONS ABOUT INSECT PHYSIOLOGY.


Principal author, Kaufman Field Guide to Insects of North America. Professional entomologist employed previously at University of Massachusetts, Chase Studio, Inc., and Cincinnati Zoo; contract work for West Virginia Department of Natural Resources, Smithsonian Institution, and Portland (Oregon) State University.

Author, Kaufman Field Guide to Insects of North America, Missouri Conservationist magazine, Ranger Rick, Birds & Blooms, Timeline (journal of the Ohio Historical Society). I have contributed to several books as well.

Oregon State University, undergraduate major in entomology, did not receive degree.

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One of the top 50 experts in all categories for, 2009.

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Principal author of the Kaufman Field Guide to Insects of North America, Smithsonian Institution (contract), Cincinnati Zoo (employer), Portland State University (contract), Chase Studio, Inc (employer), Arkansas Museum of Discovery (guest speaker). Currently seeking speaking engagements, leadership roles at nature festivals, workshops, and ecotours.

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