>Sara says "Upon closer inspection, however, I discovered that they were >chewing the surface off of the wood and leaving hundreds of small tracks. >I tried spraying the wood with bee/hornet spray but this has not deterred >them." As Lloyd points out, "these are almost certainly what we call 'Bald Faced Hornets'." We treat our teak furniture every year with a light sanding and a fresh application of teak oil. That will discourage the hornets and extend the life of the furniture. If your patio furniture includes a table, no matter how short the effective life of the insecticde is supposed to be, I'd not risk spraying a surface which might come in contact with food or the hands which will put it in my mouth. --