About a year or two (maybe more, years tend to get compressed these days, I clearly remember standing in the airport lobby watching the invasion begin in the Gulf War, and now kids that were born that year are teenagers), I replied to a similar thread on pinching. The thrust of it was a radical new approach put forth by Boon. I am surprised that Chris hasn't mentioned it. It sure opened my eyes.
The bottom line is that Boon doesn't pinch junipers, he prunes them. Now, I may have this bass ackwards because I didn't learn it from Boon, but from Jim Gremel, who is a student of Boon's eventhough he is a good teacher himself. In one of Jim's workshops we discussed this, and I was fascinated. Jim showed me one of his beautiful old Shimpaku that he and Boon had just finished 'pruning' (this was in March I believe, or early spring). It was the most beautiful juniper I had ever seen from the standpoint of the foliage, a real stunner. You just couldn't stop looking at the foliage. There were no pads! Of course there were foliage 'areas' that were loosely separated by open areas. It was completely natural and not the least bit contrived as pinched poodled junipers usually are.
I guess I remarked to Jim about how stunning his tree was, and he excitedly told me how Boon had taught him this new method of pruning junipers. He had just started it that week, so he was relating to me what Boon had shown him and what he tried with this tree, so he was a bit uncertain about the finer points. So I am relating this secondhand. I have toyed with the process, but I don't really have any junipers that are ready for detail pruning yet, but I am getting close (actually they are ready, I just don't have the time yet).
First, Jim went into the life cycle of a 'pinched' juniper. Initially, you have to create scaffold branches. These are then headed back to maintain the outline. The 'pad' is generated by pinching as described in the posts above. The problem with pinching is not that it leaves brown tips which will disappear in few weeks (correct timing is necessary before a show) but rather that pinching is an indiscriminate process. What you get is an eternally rising pad of foliage that soon creates an area dark dead area of scaffolding underneath with no live growth. You might get an optimum 'pad' every three to four years when it looks really good (if you like the poodled layer look aka the School of Green Donuts), but you then spend the rest of the years undoing what you just did to lower the pad by removing foliage and inducing new growth back into the scaffolding.
Boon's approach (if I am reading this correctly) is to treat the foliage areas more like the ramification of deciduous foliage areas. That is, the deliberate structuring of secondary and tertiary branches and twigs all the way out to the final leaf. Have you ever seen a well ramified Trident maple? They are breath taking. Even when in foliage you can see the entire structure of the foliage area. It seems an almost endless forking of tiny branches finishing in a flurry of minuscule leaves. In junipers you accomplish this not by pinching, but by deliberately selecting each green shoot using sharp fine shears, either keeping or removing the shoot by cutting it off at its base. No pinching except perhaps in the scaffolding stage where you are just selecting places for secondary branching, and browning isn't an issue because the tree isn't ready to show anyhow.
Now this may seem like a daunting task, and in fact it is. Jim said they spent something like nineteen hours pruning three of his trees. You start at the primary branching and follow out to the secondary branching where you begin to encounter green shoots. Most of the time the small green shoots in the axils of the branches is removed to maintain the fork. As you get to green shoots and wood that has just lignified (browned), you begin the process, left-right-left-right- up, left-right-left-right-up, or whatever pattern works for you. This is repeated for every foliage of the tree. Rather than indiscriminate pinching that is mindless and leaves a cushion, you get a structure that you can see through that is light, delicate, and probably most important- maintainable. Foliage area extension can be controlled by simply pruning harder to head back to secondary branching and thus shortening the branch with almost no adverse consequences. Trees treated this way can be shown every year.
Later that summer, I saw this same tree as it was in the REBS show in August. By that time, it was fuller and richer after three or four months growth, and still a stunner, but not nearly as good as I saw it immediately after Jim and Boon had pruned it, and no brown tips!
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