Well, thought I'd put this out here and see how folks feel about this stuff. Living out on natural desert land, we have many paloverdes, mesquites and smaller greythorns and such. The mistletoe is pretty abundant growing in perhaps 50% of the trees including a few very large paloverdes. We have also planted many more trees like mexican and blue PVs, chilean mesquite, sweet acacias and so they are also getting mistletoe here and there. I try to trim out smaller branches with it but some larger branches also end up with it.
Last week's high winds took one of the larger mexican PVs and bursted one of the largest branches. What I mean is the branch being about 6" in diameter stayed on the tree. But at a point 8' above the ground where the branch was still arching upward in growth, it split vertically in half for about 18" just at the spot where a small bunch of mistletoe was growing. I am 99% sure the mistletoe weakened the branch and that's why it split. So if you can imagine, the branch now looks like a mascerated stem, like a giant decides to gnaw on it so it was a stringy mess, still holding together but with a gapping ripped hole in the vertical fibers over a foot long in that one section.
Of course the branch is now drooping almost to the ground. I think we will wait a few months to trim it off as it is at least 30% of the tree - hopefully the cooler months will mean less stress on it when losing that much.
OK so got offtrack describing, but the question is: what do the tree gurus say about mistletoe? Should we try to control this stuff where we can? How? I've read it MUST be cut out but sometimes that is not very feasible given location or the fact that the branch is a main one. Is it a losing battle? Does just knocking off the growing portion of mistletoe do any good at all? I realize it grows down into the flesh of the tree which is why this branch was weakened but can you stunt the mistletoes by keeping the growing portions knocked off in cases where you don't want to prune out a major branch it appears on or where it's 20' up in a very prickly PV?
I would appreciate any discussion on this topic.
Footnote: I do realize that mistletoe beeries are one of the primary sources of food for phainopepla (black cardinal like bird) so I wouldn't want to eliminate all mistletoe. I'm just trying to minimize the possibility of losing any of the big trees or losing huge branches like what just happened. Our native trees and almost all of those we've planted (now well established) do not get regular watering or much pruning outside what we need to do to walk/drive on our land. Some of the more prized ones might get an overnight drip soak 1 or 2x a year IF drought is particularly bad in a year. But by and large these are native and totally adapted trees.