Question
We recently fertilized our lawn with Scott's Turf Builder. Now some of the leaves on our River Bottom Willow tree are turning yellow and falling off. Could the fertilizer have caused this? Is there anything I need to do to prevent any further damage?

Answer
Hi Elaine,
Thanx for your question.  Yes, garden plants, trees and shrubs often suffer from overfertilization or seepage from lawn fertilizers.  There are black plastic barriers you can use that you can sink into the soil to prevent a lot of the seepage from getting onto your tree.  Many people remove the sod from within 3 or 4 feet of the tree and cover the area with a nice looking ornamental mulch.  This gives the tree more distance from the fertilizer.  The link below shows the lawn edging.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&...

If you have a lawn service, show them the damage and ask them what they can do to keep the trees from being contaminated by the fertilizer.  I'm not really a turf expert so I'm just going by things I would do if I saw damage.  I pretty much use lawn chemicals rather sparingly.  Lawn chemicals run off into the water system and pollute ponds, lakes and rivers and I'm sure you don't want to hear a lecture about that.  With that said, there are two lawn experts on Allexperts.  You can access them by going back to Home/Garden and clicking on Landscaping and then clicking on Lawns.

I hope this helps.
Tom