I’m guessing Elvis that a “shunning tree” would be like an email version of a telephone tree which is a very effective tool for use in responding to crises which require large numbers of people to be informed of something rapidly. The idea is that I have a list of (say 5) people to ring to say “get down to the park, they’re trying to chop the 500 year old tree down”. I make my 5 calls, then leave. The 5 people each have a list of 5 people to ring. The numbers build very rapidly.
picmr