Swarm of Stinkbug Soldiers

Well, okay, not soldiers or swarm, really.

But it's an invading army nevertheless.

The brown marmorated stinkbugs haven't been around for very long, as Wikipedia reports: "The brown marmorated stink bug was accidentally introduced into the United States from China or Japan. It is believed to have hitched a ride as a stowaway in packing crates or on various types of machinery."

Accidentally introduced.
Aaaargh!

Drives me crazy now that cold weather is upon us, and the buggers are finding their way into the house.
Not a piece of firewood comes in without a hard tap on the ground to dislodge any that are sleeping on the undersides.   Since they're not small, I wonder how they get in.

But get inside they do.
Aaaargh again!

The Wikipedia gallery shows egg clusters on leaves...but look at what I found on a decorative plant at the edge of the patio:  (click photos to enlarge)

A hardened glob of mud, with some type of larvae inside. Was the stinkbug feeding?  or protecting it?

The stinkbug on the mud glob quickly met its maker 

So was the stinkbug feeding on the contents of the mud glob?
Or are those its own larvae overwintering?

The round depressions on the mud glob were interesting, and appeared as though a penny had been pressed into the mud while it was still wet.  
What made those penny-sized depressions?

A clever adversary, skilled in geometry, if it was the stinkbug.
Arrived via hitch-hiking.

"Between knapweed and stinkbug 'imports'," Kia would've suggested, "B.C. has a trade imbalance with China and Europe."

Knapweed details.