Something is eating holes in one of my maples

[21incher]

Just noticed one of my maples had started dropping leaves on one side early.  Found a bunch of small holes eaten in the bark on that side. Here's a picture.  Looks like bug holes that are slightly tapered. Wondering if I should try spraying the holes with pesticide.All on the NE side that's shaded.

[rusticretreater]

probably bark beetles.  Spray or inject pesticides asap.

[SwampDonkey]

Insects would be secondary to a greater problem already started. Those holes look more like sapsucker to me. Did you do any earth work around the roots? Maple is sensitive to having top soil laid on top of the ground, smothers the roots.

[21incher]

Insects would be secondary to a greater problem already started. Those holes look more like sapsucker to me. Did you do any earth work around the roots? Maple is sensitive to having top soil laid on top of the ground, smothers the roots.

I looked up sapsucker damage and that's exactly what the holes look like. I haven't  done dirt work but back in 1990 they bulldozed that area to level it out some when they prepped the land for our house.  It's  a big beautiful tree that ys off and only on that one side. So sounds like not much can be done. Thanks 

[thecfarm]

That's too bad.

[YellowHammer]

That's what came to mind to me, a hardheaded woodpecker getting a good meal out of your tree.  

Since the holes are arranged in the pattern of an arc, it means the woodpecker stayed in the same spot and just moved his head over to pop the next hole to find the grub.  Whenever the arc of the hole pattern changes shape, he moved over and got a new foothold.  

 

[Old Greenhorn]

Definitely Sapsucker holes, not woodpecker.  Woodpeckers will rip holes trying to uncover food. Sapsuckers just want the sap.
 Not to worry, they will heal over. I have a white oak here with the same exact thing. I doubt they are connected to your leaf die off, but if they are it should only be temporary.
 This too shall pass.

[SwampDonkey]

Sap attracts bugs, they eat the bugs on the sap holes as well as lick sap. Secondary opportunists are the hummingbirds up this way that come along and lick the sap. I've seen severe peck in some trees causing death. They keep coming back to enlarge the old holes, eventually girdling the tree.

[YellowHammer]

Definitely Sapsucker holes, not woodpecker.  

I didn't know there was a difference.  I figured a sapsucker was just a woodpecker with a straw in its beak.  

[21incher]

Definitely Sapsucker holes, not woodpecker.  Woodpeckers will rip holes trying to uncover food. Sapsuckers just want the sap.
 Not to worry, they will heal over. I have a white oak here with the same exact thing. I doubt they are connected to your leaf die off, but if they are it should only be temporary.
 This too shall pass.

The leaf die off is just on the side above  the holes. Guess  I can put the chainsaw away, wait and see what happens  next. I'll have to put a camera out there to see if it returns. 
Thanks everyone.