You may have noticed large mud nests in trees as shown adjacent.
Sometimes when the termites have moved on birds peck out the interior and a small entrance hole for a nesting box.
The common termites which build arboreal nests are called
Nasutitermes walkeri and Microcerotermes sp.
These termites have mud tunnels to connect to the ground near the base of the tree. They also have a labyrinth of tunnels underground.
What’s interesting to note is that these termites seldom do any damage to either the tree or houses.
I have, under instruction of customers who were told to remove trees because of this, dissected many nests and never found the tree eaten away. The termites seem to do a little chewing around the bark but for the most part the trees are fine other than a few mud tunnels.
Now it’s wise to ID these termites to make sure. Look for the mud tunnel, it will be there, and what I do is scrape it open to find the termites. I’ve attached a picture so you can see two termites and the exposed tunnel.The termites are quite large, maybe 7mm long, and have a distinct dark head in most cases … I do find the odd one that’s a bit different but there’s males, workers etc.
Their head is slightly pointed, like they have a beak or something, these are Nasutitermes.
Now if you are concerned the tree may have been eaten or the strength of the tree above the nest weakened then you can tap the trunk near the nest to see if it sounds hollow. There are other ways to and one is drilling with a small drill. If you are concerned about getting rid of them then I’d suggest getting a pest controller in and having them treated so the whole colony dies. But do not destroy the nest till that’s done, you need the colony functional for poisons and baits to work correctly.