Carol, I have a big butterfly that is made from welded metal that is stuck into the middle of the swamp milkweed bed. I could hang the bags there. I have a fence that could be used to hang a bag. I'm not certain if you need to create a field of light waves between two hung bags or if a single one will work. I can also hang bags between the outside corners of my small greenhouse by using the tie downs that hold the shade cloth in place. That would be a good experiment because I raise butterfly host plants in big pots along this side of the greenhouse (can't waste that strip of sunny ground) and the wasps regularly patrol these plants! It surely can't hurt to experiment, nothing ventured nothing gained. :-) BTW, all Monarch cats left on these MW plants have been taken by the wasps. I'm trying to place in the enclosure every Monarch egg or cat I come across now. I purchased wasp traps from a company in Canada that had good results reported using them up there but my 'southern' wasps just ignore the traps. LOL These wasps are the biggest threat to my little cats. I had a lot of pvst cats and the wasps have found and carried off every one of them. How do these little cats ever survive in their native habitat? Mary

You are asking good questions. Most people would just act first and ask questions later :-) If you have certain types of berry-producing plants in your garden, that will be an attractor as well. Certain berries attract specific types of birds. Yes, the Bird watching forum is what I meant to say. The posters there are very knowledgable about this topic, and they provide a lot of support to each other. With a 1.5 inch hole size, you can expect any number of bird types to check it out, depending on your location. If you are in the city, beware of House Sparrows and House Wrens, as they will attack and kill native cavity nesters such as Tufted Titmice, Chickadees, Bluebirds, etc (up to 6-7 inches in size). The bigger birds can not fit into a hole that size. Nestling it in the trees will be more attractive to Chickadees and Titmice, and less attractive to Bluebirds. But that makes it easy for squirrels to get on it and reach in for a snack. There are ways to help prevent that. Although this link is on a Bluebird web site, this page covers information about other cavity nesters. Cavity nesters will nest in all kinds of things. As for a pottery bird house, I am wondering how hot it might get outside and whether it can "breathe" like wood does. Also, if water gets inside due to wind & rain, is there a way for it to drain out? Are there some tiny holes in the bottom? It's a good idea to try the bird watching forum, there is a wealth of information there. Your questions will get some great responses. DonnaVA

You might want to check the size of the hole in the gourd also. Different birds need different size holes and if my guess is right your gourd was bought at a craft shop and they didn't take that into account. I have had swallows, bluebirds, wrens, and finches nest in mine. I did the same thing as Robin for the hanger and be sure to put the drain holes in the bottom too or your young chicks may drown. You can find books at the library that tell you what size hole for the birds you want to attract. Good Luck!

Charlie, I can't picture what you are trying to do very clearly, if you can modify a baffle to make it fit on the post like we do on the slick metal poles then go for it. If not, maybe hang decorative bird houses on your tressil posts and plug the entrance hole if it has one. Then in your yard place a proper nest box with baffle. Feel free to post on bluebird nut cafe, you will get more help there than here.