Looks like a chaste tree (Vitex). Available at Home Depot in the Triad.

There's also a pink flowered version and some that claim to be blue-er or purple-er than the normal species (they all look alike to me). The leaves kinda stink but the bushes are tough as nails and once established require no care at all - no water, no fertilizer and no pruning if you don't care how tall it gets.

Thanks a lot bartj13 and trianglejohn!

I love these trees...and I personally find the foliage to have a pleasant smell. As the OP points out, bees love it, but so do butterflies and sometimes hummingbirds as well (my hummers seem to have developed a taste for it). I have both a pink-flowering and a purple-flowering vitex, and they are truly carefree once established, and bloom their heads off for two solid months for me in full sun. You won't be disappointed if you plant one!

mfaerber..one of the best features of vitex is if you keep it small 6-8' tall you can clip off the central new growth of each flowering stalk after the first flowering and it will rebloom in a month so you have multiple blooms all season.
Japanese beetles flock to it not to eat or damage but to mate. Each morning I find sleeping baby bumblebees in the flowers. There are so many stingers attracted that hummingbirds feed on it very early in the morning while the bugs are sleeping.

I'm highly allergic to insect stings yet I have planted a pair of vitex flanking my most used back door. The abundance of 'food' for all the stingers makes them unusually calm and provides food for honeybees all season if you keep it flowering.
It flowers only on new growth and a vitex trimmed way back in fall or winter will add 6-8 feet of new growth.
Watch for water sprouts..the long straight branches that sap the strength of the tree..keep them trimmed out.
It can be trimmed up so the lower branches are very attractively zig-zagged for winter interest also. Each trimmed spot will sprout new branches in the spring so you can continue with judicious snipping to add to the zig-zag appearance of branching.

The only negative to growing vitex is you have a great deal of trimming to do each season and lots to dispose of.
At my other house, the main vitex is now about 20-25' tall and about 15' wide..when I moved my DS let it go untrimmed.

My vitex here are planted within 4 feet of the foundation with no problem at all and their roots extend to under a sidewalk but are small so also no problem.
I can plant right under them at any time ,clearing the small roots as I go and the tree doesn't suffer.
They make wonderful small shade trees for windows that want winter sun and summer shade.