Will an old stump attract termites?
Yes, eventually, but an old stump feeds termites already living in the yard. NC State Extension says yard stumps will in time become termite food, calls termites "part of nature's way of recycling dead wood," and says swarmers outdoors near stumps are not an indication that the house is infested. Its termite publication warns about stumps left under houses.
A yard stump feeds termites already in the soil
Subterranean termites normally live below ground in colonies often found near a tree, a stump or a wood pile, NC State Extension says, and the eastern subterranean termite can be found in every county in the state. In NC State's words: "You really do want termites in your yard; but you do not want them in your home."
NC State's swarmer publication adds that a colony settling away from the home may later send swarmers to attack a home left unprotected. None of the NC State Extension or NCDA&CS pages read for this answer says grinding a yard stump keeps termites out of a house; grinding itself is detailed on stump grinding. Carpenter ants, which NC State Extension says do not eat wood whereas termites do, are read separately on sawdust and carpenter ants.
A stump under the house can feed termites
A stump left under a house is the case NC State's termite publication names: it says wood, cardboard or paper stored in a crawl space can serve as termite food, and that "The same problem arises when tree stumps are left under houses during construction." The NCDA&CS consumer page on termite control lists, among its preventive measures, "Remove all stumps, dead wood, and other cellulose containing material in contact with the soil from the crawl space."
Whether a stump under a porch, a slab or an addition is ground or dug out changes what stays in the ground, as stump grinding vs stump removal explains.
How far is the old stump from the foundation, the porch or the crawl space?
Questions people actually ask.
What does it mean when termites swarm inside the house?
Indoor swarming usually means an infestation somewhere within the house, NC State Extension says; another of its publications calls swarmers indoors "most certainly a sign of active infestation."
What termite signs can be checked at the foundation?
Termite mud tubes and hollow-sounding wood, per NC State Extension: tubes of soil and wood particles on foundation walls, floor joists and in crawl spaces, and wood that sounds hollow when tapped with a screwdriver handle.
How are termite swarmers told apart from winged ants?
NC State Extension lists three differences: termite swarmers have straight, beaded antennae, four wings of roughly equal size and shape, and a broad waist, while winged ants have elbowed antennae, larger front wings and a pinched waist.
Who checks a house for termites?
NC State Extension sends tubes or damaged wood to "a professional pest management service" and recommends having a structure checked by one once a year; for telling termites from ants, it names the county Extension center, such as the Davidson County Center.