One he says that redwoods get to be over 30 foot in diameter. I have never seen a 30 foot diameter redwood. The largest about 23 foot, and it was a double.
Another, he says "Ants are never found in redwoods" Ants live in redwoods by the tens of thousands.
Another, "Redwoods graft themselves together purposely to grow more structure." As in all trees grafts are purely chance and the tree does not think it out.
He also overstates the average age of the redwoods by over twice as much.
There's more, and especially in his book. His accounts of the redwoods are more ecstatic than factual. Yet he is regarded as being an expert on redwoods. Funny how that goes.