Question
QUESTION: William,

I have 2 big Poplars in front of my house.  One is really thin now and leaves are dropping and looks like it is dying.  They both have discoloration around the base of their trunks.  It is almost a white or yellow color and the flare looks like it is starting to rot.  Any ideas how to stop this or what caused this?

Shane

ANSWER: Hi there. Can you give me some more info
Where are you located
How old or how tall are the trees
when did the symptoms start
location of the trees in relationship to house,road drive way etc.
Thanks,Bill

---------- FOLLOW-UP ----------

QUESTION: Bill,

We are located in Northern Virginia.  The trees are approx 70'ft. tall.  The symptoms began earlier this year.  The trees are approx 5'ft. from the sidewalk and a retaining wall.  The retaining wall was put in in 2006.  New sod was put in at that time in the front yard (around the trees) at that time as well. I hope this helps.

Thanks,
Shane

Answer
Hi. It sounds like the roots were cut when the wall was put in.If you are seeing decay in the roots you could have a very hazardous situation.Root rot usually starts at the bottom of the root and works it's way to the top.(Chances are the entire root is decayed)Cutting the roots within 5 feet of a 70 foot tree means you have cut major anchor roots.The rule of thumb for root cutting is at least 1.5 feet away from the trunk for every inch of trunk diameter. In other words a 20 inch diameter tree should be undisturbed at least 30 feet from the trunk. To make matters worse it sounds like you covered the root system.(with sod)This can suffocate the tree.
I would strongly suggest you have a certified arborist familiar with hazard tree inspection come and look at your trees.
Sorry to be the bearer of bad news but it does not sound good.

Let me know how you make out.  Thanks,Bill