Protecting from deer. Long ago they would sometimes use a device called a FORMER. Usually it was made of wooden stakes and wire mesh in the geometric shape that was desired to train the evergreen. At first an arborvitae should be shaped without a former in order to get it to produce the multiple branching and general shape. Then the former should be built over the top of the shrub so that a single years growth will start to extend beyond the wire mesh. In a short period of time the former will be invisible until the evergreen is sheered back to it. This picture, taken in Gilboa, NY something similar to a former is being used to feed the deer while maintaining a sufficient amount of foliage for continuity. As the foliage extends through the mesh its trimmed off by the deer.
I like the idea of shaping the fence into a pyramid, cube or other topiary shape and allowing the deer to do the work of pruning. If you fertilize in spring new growth will soon disguise the fencing to be removed the following winter.
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