Dennis is looking at a soil fungus -- and I might buy that if this collapse  
was in a specific climatic zone, time of year.  The grasshoppers I worked  
with years ago had a high attrition rate of nymphs when molting occurred in wet  
weather.   But again, we've got all regions, all times of year,  different 
soil types, etc.
 
And, as you say, frames tend to get covered with fungus/mold in  spring.  So 
fungi in gut may/may not mean anything.
 
Jerry

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