What Are Moisture Ants?
Moisture Ants or “Yellow Ants” as they are sometimes called usually refer to a genus of ant called Lasius. The type found in homes is typically 4-5mm long, and yellow to reddish-brown in coloration. Moisture Ants are Wood Destroying Organisms, which exploit damp or rotten wood to excavate nests. Over time, they can do significant damage to wooden structures.
Moisture Ants vs. Other Ants
In the Pacific Northwest, Moisture Ants are most commonly confused with Carpenter Ants or Velvety Tree Ants. All three of these ants are Wood Destroying Organisms; however, Moisture Ants cannot excavate dry hardwoods. They can circumvent this limitation by carrying damp soil to the wood to induce rot, a process that softens the wood enough for the ants to make galleries. Carpenter Ants in a structure will leave coarse frass resembling sawdust from their galleries, whereas Velvety Tree Ants will leave a finer powder. Moisture Ants create “carton-like” galleries made of soil and the own ants’ secretions. These galleries are often woven into insulation & have a dark, crumbly texture resembling fungus. As always, capturing a specimen is the best way to make a clear identification.
Moisture Ants vs. Termites
Moisture Ant activity is often mistaken for Termites due to the tendency to gather soil and bring it to the wood. Additionally, the presence of wet or rotting wood can also attract Dampwood Termites or even Subterranean Termites; Termites and Ants can infest the same structure. The key difference between Wood Destroying ants & Termites is that ants do not eat the wood; they excavate it to create nests. As such, there will be accumulations of frass from the excavated wood. Termites will instead produce fecal pellets as the wood is consumed & digested.
How to Find Moisture Ant Nests
Typically Moisture Ant nests are located by tracing the foraging ants as they leave the structure, typically on the exterior foundation or in the crawl space. It is critical to remove soil touching the siding, as Moisture Ants can burrow from the soil to the siding without ever becoming visible otherwise. When attempting to locate a nest inside an interior wall, a Moisture Meter and a small rubber mallet can be useful tools. The nests will be sufficiently wet that they should register on the Meter. Tapping the wall with the mallet can cause soil or frass to spill out if the bottom is unsecured/unfinished. Moisture Ant nests can cover a wide area, and it is not unusual for an entire wall to be infested if sufficient moisture exists.
How to Get Rid of Moisture Ants
For immediate results, injecting nest areas with an appropriately labeled insecticide will eliminate the nest. Generally, a foam formulation is preferred, as that penetrates the insulation, carton substrate better, and will fill the void completely. Treating the exterior perimeter and the crawlspace is also advised. It will be necessary to remove conducive conditions such as soil touching the siding for this treatment to be fully effective. When infestation is removed, it is best to replace any rotted or damaged wood and correct any sources of water damage that may have led to the infestation in the first place.
Contact Wayfare Pest Solution
If you think that your house has been infested by Moisture Ants and need help finding a pest solution, contact us for more information or to schedule a service.