If trees were left to nature and in their natural setting then an arborist wouldn't need to develop modification techniques. For example, I've been consulting with a developer who it putting in a planned community in what was a second growth conifer forest (Red cedar, Douglas fir, western hemlock) up to 160" tall. Largest diameter was about 4'. So most of the trees were tall and skinny with no taper and a crown size of less than 30% of total height. Growing in a forest setting these trees (particularily the codominant layer) are supported by their neighours, but once the land is cleared for housing, the edge trees are now subjected to wind stresses they were never subjected to before. Their stem or root growth is different than an open grown tree.
Now, as the arborist, you need to make modification because the environment has changed. Unfortunately, stripping the forest edge back to a safe distance isn't always an option due to planning or environmental regulations, so tree modification prescriptions have to be made. At this point, in this situation, windsail reduction is the most viable one I've seen.
A valid point, well taken in that it acknowledges it's a man made problem being addressed by man that is inflicted on the forest to benefit man at the expense of the cleared trees.
Arborists do their best hopefully to accomodate trees to mans flawed ideas of a sustainable environment for them.
Erythrina caffra the african coral tree in almost every socal community is a perfect example of a marvelously exotic softwood, almost succulent like tree that almost every commercial climber who's ever climbed one has either fallen out of completely or broken out of completely. In their natural settings they are drought resistant requiring minimal water and nutrients to survive and sprout their huge clusters of crimson orangish flowers each year.
But plopped into the typical socal landscape they are overwatered, over fertilized, planted in lawns where they go totally ape crazy growing at unbelievable rates of speed such that every sping and early summer they basically self destruct by the hundreds and thousands unless they are pruned back hard every six months. These trees in these unnatural settings being pruned so hard so frequently never seem to flower because of all the new tertiary sprouting. Each early summer here in socal is coral breakout season, and climbers breakout and hit the ground with them every year.
Fortunately these trees do not generally get big enough that the fall is very far as they tend to grow wide rather than tall so that even a tied in climber usually hits the ground when the branch he's standing on breaks out from under him.
Naturally most arborists that can get to these out of place time bombs with a bucket, use them to safely prune them with. But there are probably millions of them that can't be reached with a bucket for one reason or another, and it takes an experienced climber to prune them without ending up a frustrated bloody mess and then breaking out of them and hitting the ground also, you see they have the most wicked razor sharp black thorns on their wood structure aplenty.
It's an arborist nightmare unless it is maintained and grown in a low water low nutrient environment, as it does so well and beautifully in it's natural setting.
Just one example of a tree introduced into the modern world and going wild as it demands arboricultural maintenance on a biannual basis or else!
jomoco
