If you suddenly discover hornets in the lilac bush in your garden, you might think that the large insects are building a nest there. But they only feed there.
In late summer, especially in dry summers, the hornets are attracted by the sweet scent of the lilac. Then they gnaw on smaller shoots of the lilac to get the sweet sap of the lilac bush. For the hornets, this is a kind of energy drink in preparation for the colder nights ahead. Until the end of their life in late September, they eat as much as they can.
But you don’t have to be afraid. Hornets are not nearly as pushy and aggressive as wasps – otherwise I wouldn’t have dared to get so close for the photos. The big hummers are peaceful and even if they fly at your head in confusion, they simply turn away afterwards.
The hornets do not cause too much damage to the lilacs either. Although some leaves of younger shoots may turn brown, the lilac is resistant. The wounds grow over again when the hornets have gone.
A positive side effect: hornets also eat wasps, which are also attracted by the escaping lilac sap. Since the hornets moved in, we have practically no wasps on the terrace any more.