The following article debunks the t/R <3.0-3.5> ratio and it has seriously questioned the validity of using the t/R formula to predict stem failure for all trees.  Could you please forward this to all CAV members. I am trying to get a copy of an article written by a German scientist who also questions the t/R formula.  No luck yet and I'll probably have to get is translated if I manage to obtain a copy.