I recently pulled up the stump/roots of a shrub that was about 2 feet from my house, and think it might have been, or was being eaten by termites. We cut the shrub down last year, so the stump was dead, but not obviously riddled by any kind of insects. I don't think there are termites in the walls of the house, and would really like to keep it that way. Should I be concerned about the stump?

I am no expert - but it might be worth the $100 to call a place like Terminex & have them do an inspection of your home. Good Luck!

Look at the foundation both inside & out, the exterior siding, etc and look for shelter tubes. These are lines of mud that the termites travel in.

The termites that do the damage are white and about an 1/8" long.
In the spring if you see "flying ants" but in a swarm situation these are swarming termites. Usually from where they start to swarm you will see wings that are transparent in color about an 1/4" long.

If you have a basement with visible framing get a screw driver and probe the areas of the joists and sill plates along the foundation. If you have damage the screw driver will imbed easily into the framing. Also look for the shelter tubes.

Termites need moisture to thrive. So if you have high humidity in the house or poor draininage against the house where the moisture is constant this is a good environment for termites.

Determining if their in your walls is difficult w/o proper tools (usually scopes that look into walls) unless ou want to cut open the wall down near the floor area of the wall.