Question
Hi, We have a spectic system in the back, followed by power lines which are about 15 feet away.  I would like to plant fast growing evergreens that have a vertical root sytem such that they do not get to spectic system and give us a cover from the power lines all year long.  Which ones would you recommend?  Additionally, when is a good time to plant them?  Thanks a lot for your help.


Answer
Here is a chart that shows species of trees that should an should not be planted near septic lines.

Selecting Trees For Planting Near Your Septic Leach Field


Not Recommended for Planting
Near Leach Fields    


  
Beeches
Birches
Elms
Poplars
Red Maple
Silver Maple
Willows     
Fagus spp.
Betula spp.
Ulmus spp.
Populus spp.
Acer rubrum
Acer saccharinum
Salix spp.

Better Choices for Planting
Near Leach Fields   
    
Cherries
Crabapples
Dogwoods
Hemlock
Oaks (red, scarlet, white)
Pines
Sourwood     
Prunus spp.
Malus spp.
Cornus spp
Tsuga spp.
Quercus (rubra, coccinea, alba)
Pinus spp.
Oxydendrum arboreum  
Here is the whole article that talks about Planting on your Septic Drain Field: Web link: As far as timeing the fall is the best time to plant trees. http://www.ext.vt.edu/pubs/envirohort/426-617/426-617.html