Answer: What type of soil moisture does this area have? The potato type bugs (Roly-Poly's, Pill Bugs, Sow Bugs, etc.) like to hang out in damp spots where decomposition is taking place. It sounds like there is too much standing water where these trees are located and they are starting to rot. It doesn't sound like they have been thriving for awhile, 25' with a 4" trunk or 7' with a 2" trunk is not good development. My first guess would be excessive moisture, this often calls a failure to thrive in trees resulting in stunted growth and eventually, rot. The remedy of course is to change the amount of water in the soil which of course is often most difficult. If I am off base with the soil moisture, please post another question via the website and let me know, we will investigate other cause of your trees' demise.
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