Have you ever wondered how termites get into your house without you noticing? They build what are called mud tubes from the ground up to an entry point into the home.
The problem with these tubes is they are very easy to miss if you are not looking closely. As you can see in the video, they are small and often blend in with the color of the concrete or foundation.
When a tube is active, you can knock part of it down and usually see termites moving back and forth inside. But knocking the tube down does not get rid of the termites. They will simply move over and build another tube. They only need an opening about 1/32 of an inch to get into a house.
If you see mud tubes on your home, it is usually safe to assume termites are already feeding inside, so it is important to act fast.