Two dead ash trees

[Timberline]

I have two big dead ash trees on a lot next to my house. I've cut down trees before but I'm thinking I should probably be concerned about how large and dead these are. Is this valid? Curious to hear what others thoughts are. I highlighted where some power lines are located.

[Ron Scott]

Hire the services of a professional Tree Service Company to fall the trees for you if you do not have the experience in falling such dead trees. 

Such trees can be very hazardous for the inexperienced, especially when power lines are within the falling area. 

To save on cost, you can choose to do the tree bucking and clean up yourself once the trees are safely on the ground, especially if you need firewood.

[Southside]

What Ron said can't be overstated. Dead Ash are bombs waiting to go off. The problem is that by the time we recognize they are dead they have been compromised for a couple of years and the fiber has really begun to degrade. Often they will snap off 20' or so off the ground when falling them as they have so little structure holding them together. 

You are wise to ask about these two, they are not your average tree to drop. 

[Timberline]

I appreciate that. I will leave it to the professionals. Thank you for your input.

[Brad_bb]

Yes, be concerned.  All the bark is already gone and they will eventually fall. Bacterial rot will compromise the strength across the grain, also there are probably insects at work in the base of the tree.  It will rot quicker at the base and fall.  About 2 months ago one fell from my neighbor across the property line across my horse trail, damaging some of my trees.  I had to pay for the tree service to remove it as it was caught in other trees above, causing a couple hackberry stems to have to come down and a Cherry and oak trimmed as well.  The good news is I did get the lowest 12' log and the wood was still good because it was large diameter and there were no water entry points above.  The base had rotted and the tree fell.