Ask Mr. Smarty Plants

You do have a bit of a challenge on your hands and I am a bit confused by your description, so I am not sure how precise my answer can be, but it may point you in the right direction.

You say the area is on a bit of a hill and there are drainage problems.  Usually a slope means there is excellent (some time too much) drainage but perhaps the plants will be sitting at the base of the slope where the water collects.  Those would be two entirely different situations and plant selection would be quite different in the two scenarios.  Also when you say the exposure is southwestern, does that mean that to have the hedge planted between your house and the pine trees, they would be oriented northeast and be shaded by the pine trees.  Or are you thinking you will plant the hedge on the far side of the pines so as not to take up any more of your back yard?

Whatever you plant will have to compete with very established tree roots for water and nutrients.  It will be difficult to dig holes large enough to plant in so you will want to start with small, relatively inexpensive plants.  In any case you will want to select a "large shrub" or a very "small multi-stemmed tree" instead of a tree.  You are already living with the reason why. 

Our Native Plant Database will generate a list of plants native to NJ that fit your critera by doing a Combination Search.  Select: NJ/shrub/your soil moisture and light conditions/and a height requirement of 6-12 feet.  The list it generates has links to detailed plant information pages.  If you have your heart set on an evergreen hedge you may be disappointed to know that there are only two on the list:

Ilex glabra (Inkberry)

Taxus canadensis (American yew) which deer love to eat

If you are willing to have less of a screen in the wintertime there are a number of large deciduous shrubs that will not only do the job but will also provide much needed wildlife habitat with flowers and fruit and fall color too.  You might want to install a fence that is not entirely solid between the hedge and the pines to prvide more privacy and a "backdrop" for the shrubs.

You should consider:

Clethra alnifolia (Coastal sweet pepperbush) which has a spicey sweet fragrance and clear yellow fall color

Cornus sericea (Redosier dogwood) whose bright red twigs give winter interest

Hamamelis virginiana (Witch hazel) which flowers in winter and has yellow fall color

Ilex verticillata (Common winterberry) which loses its leaves but has red berries along the length of its branches (as long as you plant a female and have a male nearby)

Morella pensylvanica (Northern bayberry) whose leaves turn tan but stay on the plant most of the winter

Viburnum opulus var. americanum (American cranberry bush) which has great fall colour and red berries that birds love

Here are some photos from our Image Gallery:

Ilex glabra

Clethra alnifolia

Cornus sericea

Hamamelis virginiana

Ilex verticillata

Morella pensylvanica

Viburnum opulus var. americanum