Question
I have a question concerning a small plot of land (17'wide x 25'deep facing east/west)located behind a townhouse in Manhattan.  Currently, there is a large, old Black Locust in the southwestern corner.  At the far western border is an 8' wall, behind which is a supermarket with a generator.  I would like to plant a fast growing evergreen of some kind that will eventually screen out the supermarket view.

Will the black locust provide too much shade even if I cut it back?  What trees would you recommend that would provide screening through the winter.  I would probably trim the lower branches up to 8'.

Thanks so much.

Stephen

Answer
you do not want to cut the top larger branches back on the locust tree as this will harm the tree and force lower growth on the tree. instead remove some of the lower lateral (side) branches to allow more light to enter the area and aid in air circulation. locust trees do not usually give dense shade because of their small leaf arrangement. it will compete for nutrients w/the new plantings. i'd recommend going to your local garden center/nursery to see what they sell and recommend for the area. you may have to visit more than one to find someone knowledgeable. i recommend arborvitae (thuja) such as thuja eligantisma, plicata, emerald green, etc. you want to get one that will get about 12' tall and 6-8' wide at maturity. some thuja (american nigra, etc.) will get 25-30' tall. the smaller growing varieties are easier to keep the same size by yearly pruning. buy the largest you can afford (you'll probably have to order them) and they will be good size about 5 years from now. if you buy smaller (3-4') it will take about 10 years. plant about 4 of them in line 8' out from the fence. plant them about 6-10' apart.
be sure to fertize them once in the early spring and again in early fall w/hollytone by espoma. this will keep them green and healthy.
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