Question
I have 4 Italian Cypress trees in front of my house in Missouri City, Texas.  I have no problem and they are very healthy except they have grown considerably higher than the roof of my house;this causes a problem in high winds since they seem top heavy.  I have one with a major problem which is the fact that about 15 feet up it has grown what appears to be a second trunk making this a wide and very heavy upper tree in the wind and it has fallen on the gutters during a recent hurricane.  The tree was reset in the ground and staked and appears to be doing fine but it is obviously still a problem.  My questions:  1.  Can I remove the second trunk maybe 10 feet above where it begins and 2.  Can I top these trees cutting down about a third of their height and keep it there.  They go maybe 35 to 40 feet high at this time.  3. What time of the year is the best time to do the cutting.  Any suggestions on my issues beyond what I have suggested. Thanks for your help.

Answer
It may survive but will only be a bush since the terminal was cut.
Almost any conifer can be used as a hedge. The best are those that shear easily and resprout from old wood. Italian cypress does not resprout from old wood and will not grow new branches where there are none. The trees can grow to 60 feet tall and 3 feet wide. Spacing of trees when planting should be at 3 feet. These trees are the classic formal column of Italian gardens.

Never prune evergreens without checking with an expert. Topping ruins most trees and is especially bad for conifers. Removing the growing point can ruin an evergreen. If trees have outgrown their usefulness as a privacy screen, perhaps removal and replacement with an evergreen species that can be easily maintained and has the growing characteristic that meet your landscape needs for privacy.

The "second" trunk is more than likely a forked tree that comes from genetics. If you are going to cut it off cut it back to the trunk. This will more than likely leave a lopsided tree crown. The time to cut would be during the dormant season and before the hardwood trees leaf out in the spring.