Your point is overstated. If the leader of a blue spruce is broken or cut
off, one nearby young branch will take over as the leader, and the tree will
continue to grow like a tree, not a bush. Last year I had 3 twigs vying to
be the leader and growing vertically. Now the dominant one has been
determined, I wonder how, and the other 2 are turning horizontal.

Sometimes 2 leader candidates both continue to grow vertically and you get 2
trunks. Apical dominance seems to be effective only near the very top, and
once they grow long enough with side branches, neither will turn horizontal.


"Stephen Henning" wrote in message
news
wrote:

Is it recommended that one of the two top tips be cut off and if so,
which one. the lower or the upper.

Yes and always cut off the lower one, never the highest one. Most
spruce, and especially Colorado Blue Spruce, have a type of apical
dominance that does not transfer to lower branches like it does in most
other plants. This means that if you cut the leader off a spruce, you
will probably end up with a bush and not a tree.

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