Why is that house in a tent?
This is a structural fumigation. Fumigations are done to control certain wood destroying insects. In our area the most common reason to fumigate is drywood termites.
The Life of Drywood Termites
What's in a name? For one thing, you can tell by the name where a termite's nest will be found. A Drywood Termite colony will be found in dry wood. A Subterranean Termite colony will be underground.
Drywood termites are much less sensitive to dehydration than Subterranean Termites. This adaptation lets them live above ground, inside of dry wood. In fact, the wood framing of almost any building has enough moisture to keep them going.
These insects are designed to make the most of their role in the world. Aside from having a thicker shell (to handle the dry environment), their social system and caste system is adapted to this role as well.
Like most termites, a Drywood Termite colony begins with a pair of mated swarmers (alates). We usually look for Drywood swarms during the late summer and into autumn. However you might see them at virtually any time of year. The evidence most people find after swarming is a collection of loose wings on a window sill. (See photo at right.) At this point the insects have shed their wings and already burrowed into the woodwork.
After swarming from their parent's colony the new royal pair needs to find a place to build their nest. A crack or crevice will serve them nicely. In buildings they often start around wood windows or doorways or they may be found in the eaves or in the substructure area under the house. Houses with wood siding tend to be especially vulnerable because there are so many cracks and crevices where a new colony might establish. In nature, we find them in the "dead arm" of a tree, in a woodpile, or in any other dead wood.
Once established, the new colony will grow slowly, but steadily. After a few years the colony may have eaten their way well into the framing around their initial entry point. A mature colony may grow to several thousand members. Given time, their galleries may extend into wall framing in all directions, into substructure timbers and floors and into the ceiling overhead.
The only evidence of their activity inside the wall or floor might be a pile of "seed-like" pellets that continue to appear even after cleaning them up. These pellets are the fecal material of the termites and it is a positive sign that Drywood termites have been at work.
After just three to five years, a few swarmers will usually be released, and the cycle continues...