Termite Control: Matching the Treatment to the Problem

Editor’s note: Dr. Michael Waldvogel gave a presentation, on which the following article is based, as part of the “Getting the Best of Pests” webinar training series from the University of Georgia’s College of Agricultural and Environmental Sciences. Learn more at https://gtbop.com.

Most pest management professionals will tell you that things on a job aren’t always what they seem. Dr. Michael Waldvogel, extension associate professor in the Department of Entomology and Plant Pathology at North Carolina State University, says the real key to successfully resolving a pest control issue is truly being able to recognize the problem.

“Look at the problem, and then you figure out your course of treatment,” said Waldvogel. “It (shouldn’t be), ‘These are the ways I normally treat a house and somehow I’m going to make them fix the problem.’ It’s, ‘I’ve got to be prepared to think outside the box.’”

In his 24 years of extension experience, Waldvogel has encountered a number of curveballs that forced him to think outside the box. Like most PMPs, while treating homes for termites he’s dealt with everything from sump pumps and crawlspaces to Superior Wall Systems (concrete prefabricated walls with metal studs) with French drains.

SPECIFIC EXAMPLES. One unusual and memorable occasion he recalled was a treatment with his friend. “My friend Scott here is drilling across a fill porch, which looks fine and then he’s going to down drill or down right into the soil beneath it,” he said. “But if you go into the crawlspace it’s kind of interesting as you notice there’s no band on this house — it’s got the manufactured floor joist. There’s the sill plate but there’s no band.”

Because of this, Waldvogel watched the rod come down into the soil, and even saw the soil subsiding in some places due to moisture in the crawlspace.

“That’s kind of just a unique one, but it’s a reminder too if you work solo on termite jobs,” he said, “you really need to be thoroughly prepared for what could be going on there. Make sure you’re prepared to address any problems.”

Even in a home with a typical basement structure, he said it is important to inspect the exterior of the house, but to not plan a course of action until checking the basement thoroughly as well.

“I was working with a company and they had a new service technician. I was explaining (about how inside the basement) there was a crack in the foundation wall, and of course you’ve got a sump pump right here,” said Waldvogel. “So, I said, you really need to watch this in case something goes wrong. And just as I said it, that probably triggered it. We had some tremendous PSI coming through that crack. Fortunately, I was prepared to deal with this by stripping off my crawl suit and dropping it right there to absorb the chemical.”

Cracks in the foundation should always raise a red flag, and technicians need to be prepared to deal with them. There are a couple of treatment methods to try when treating the exterior; one is to cut the volume of spray in half to help reduce seepage, Waldvogel said.

“Instead of going out at 4 gallons per 10 feet per foot of depth we went out with 2 gallons per 10. But at the same time of course you have to double your amount of chemical because even if you cut your volume of spray you still have to deposit the correct amount or labeled amount of chemical along that foundation wall.”

NON-LIQUID TREATMENTS. Installing termite bait stations along the exterior is another solution. “You’ve got to size it up as what overall in terms that structure is your best option,” said Waldvogel.

Landscaping also can be a factor when deciding on a course of action, especially if it’s flush up against the wall or close to edible plants.

“Do they have an herb garden in that area where you are going to treat and is it within the barrier that you’re supposed to maintain between the chemical and the plants?” he asked. “Just because someone says, ‘Well this is just a decorative herb garden,’ that doesn’t mean they’re not going to forget it or their neighbors are going to come over because they saw this really nice-looking sage there that they’d like to use.”

Insulation in a crawlspace can throw a wrench into a typical termite treatment plan.

“First of all, how are you going to inspect it to see if they’ve got termites?” asked Waldvogel. “How are you going to treat it? And then if you do decide to treat it, how are you going to come back on your annual to inspect it to see if there’s any source of problems that have persisted or all of a sudden occurred?”

There are several options for dealing with this scenario, he said.

One option is simply walking away from the job. Waldvogel said there are some situations where declining the job is the best option because signing your name to the contract makes you accountable to both the customer and the state for its successful and safe completion.

However, when a technician does decide to take on an insulation project like previously mentioned, it is important to consider that taking the insulation down can be negating a contract with the insulation company.

“You’re going to go in and cut the (poly down) so you can trench and treat, that again is compromising this other piece of work, just as you don’t want them compromising your work by say trenching and putting in a bunch of plants where you’ve already just treated the soil,” he said.

In a similar situation, Waldvogel told the customer that in order to perform the termite treatment, the technicians would need to remove insulation. After removing the insulation, Waldvogel determined that the structure might not be able to withstand a “drill and treat” application, so he recommended having a construction contractor come in to inspect it as well.

ANOTHER PERSPECTIVE. Observing structural changes to a home throughout the years also can make things easier when a PMP arrives on site. That’s why one of Waldvogel’s favorite resources when treating a house are the pictures included with online tax records.

“You can often see pictures of the house that you’re going to be called out to check,” he said. “We actually often have a footprint of the building as well so that kind of serves as a guide when you’re graphing it if you’re proposing a treatment of some sort.”

The pictures and diagrams can uncover changes, like additions, which may affect the amount of moisture in the soil, hidden insulated concrete forms or different finishing materials (like real vs. synthetic stucco) that can be hiding nutrition sources for the termites.

“My point here again is really make sure you’re thorough and you know what not only what’s inside the house, inside the crawlspace, but you check the exterior so you know what kind of coverings there are because those coverings could also be covering termite activity as well,” said Waldvogel.

It’s also important to see any additions that might hinder you from ensuring the customer does not have a continuing termite problem during your annual visits. Waldvogel said maintaining a 2- to 4-inch gap where you can see the foundation is crucial to ensuring the customer’s structure is termite free.

“You need to have a gap so that you can see the actual foundation wall because if you’re going to go back every year and tell the customer, ‘You do not have a termite problem,’ you better know that you’re being accurate in that particular case,” he said. “So, we want to make sure you have access to a visual spot to check for any new termite activity.”

You can also see additions like French drains, which if unnoticed, can leave a liquid treatment running into a neighbor’s yard or into the street and sewer system.

Waldvogel says if a PMP finds Superior Wall System construction, it means there is a French drains in place. Superior Walls are essentially pre-cast concrete panels that are about 8 to 10 feet tall. The expansion joints between the pre-cast panels and interior ports are a weak spot that could potentially be an entry point for termites.

They’re also not put on a solid footer; they’re on gravel instead. When trenching the exterior of a Superior Wall System, a pest management professional would hit gravel quickly, which is the footer of the structure itself. There’s no treatable soil except for the soil lining the trench. There is, however, usually a French drain about 18 inches off of the wall.

“We’re seeing more of this crop up both on our coastal areas and over in the mountains where you have a lot of people putting up very large houses,” said Waldvogel. “By the time you go in and look at this house and you quizzed the homeowner they probably don’t even know what you’re talking about. They probably don’t even know they’re called Superior Walls unless they have an unfinished basement and can see the panels. But it’s something you need to be quickly aware of.”

It’s also something that is hidden once the drywall is up.

Waldvogel said Google Earth is another great tool for planning treatments, especially when determining if there are drains nearby.

“Your concern here is…you blow out a hose line or something, and you now have chemical streaming down this driveway heading for that drain,” he said.

But once a PMP identifies the drain, precautions like running numbers on the amount of chemical actually needed to treat the house and covering the drain with sheeting and sand snakes can be taken.

“The next question that you have to ask yourself is where does that drain go, and this applies also again going back to regular French drains,” Waldvogel said. If possible, put a 5-gallon bucket at the end of the drain see if any liquid comes out.

TOUGH JOBS. Older buildings can hide just as many problems for pest management professionals as new additions, as Waldvogel experienced when he treated a 200-year-old Scottish Rite temple.

When he went down to the basement to look at the termite problem, his team found a wall that no one knew was there. They decided not to open it up, but did ask for a drawing of the original building.

“They pulled out this picture of a picket fence and there was a Union soldier standing there in the picture,” he said. “So, this building has a long, storied history.”

It also had severe moisture wood decay and an aerial infestation.

“This is where your ability to treat it depends upon the problem,” Waldvogel said. “In this case, a liquid termite treatment in just the soil is not going to fix this kind of a situation.”

Waldvogel addressed the problem as if the termites were active in the infested walls, so they drilled into the walls and foamed them. He double checked his expansion ratios and foamed a liquid chemical for the job.

“You don’t want your foam overly wet, especially if you’re treating an area where there’s drywall,” he said. “You also don’t want it too dry, you want to make sure it expands quickly inside that wall and coats the inner surfaces, as well as saturating hopefully any termite tubes that are going inside there.”

Although above-ground bait stations could have been a solution, Waldvogel said the owners didn’t want them visible in meeting rooms.

“It’s always going to be your customer’s decision (but) sometimes you just have to convince a homeowner maybe you’ve gone through this, and that is just not reasonable,” he said. Waldvogel stressed that technicians are the experts and going with the solution they know is best will save time and trouble in the long run.

While working on a support porch, Waldvogel addressed termite activity by drilling but continued to just miss a pocket where termite activity was coming up through the soil. Even more importantly, he said, was that the wood was severely decayed. “It’s quite possible that even though we treated the soil here the termite activity continued because the termites weren’t going back to the soil, and that’s always the problem when you get essentially a secondary or above-ground infestation,” he said. “You can put all the chemical in the ground you want. If the termites aren’t coming down there it’s not going to affect them.”

He decided to use a needle injection tip to shoot the chemical directly into the wood. “All the termite activity stopped subsequently,” Waldvogel said. “It told us again, an example where if we had looked at this really closely from the start, we probably should have gone in and done this in the first place.”

Waldvogel related the following story to illustrate the importance of following label instructions. While working on a support porch, Waldvogel encountered a tree stump and lumber near a crawlspace that had termite activity. The only activity was in the stump, but Waldvogel first performed a conventional exterior treatment on the house “to prove the point that there’s a reason why we follow the product labels when we treat any house.”

“We treated the entire exterior of this house and lo and behold the termites that were fat and happy eating the stump under the house couldn’t care less because they didn’t even know we treated the outside,” he said.

After coming back several months in a row and seeing no change, they treated the interior and exterior wall in the area that was affected, and six months later, no more termites.

“You have to do it the hard way by trenching and treating around the house if you’re going with a liquid or installing bait stations,” Waldvogel said. “…This is why the label tells you to do that interior treatment where it’s needed.”

Waldvogel sums up his experience with a simple sentiment — think about your plan for treatment and don’t take shortcuts. Walk that structure carefully and look inside, outside and even at the slab.

“The more thorough you are, the more likely you are going to succeed,” he said. “So, make sure you understand the problem.”

The author is a Cleveland-based writer who can be contacted at lstraub@gie.net.