I tried to do the "quick reply" but was way over the permitted number of letters -- tried unsuccessfully several times to cut it down but the message was still too long. Hence a new post after condensing as far as I dared to and have it still make sense.
I found how to make your own WASP trap in my files from
http://completegarden.wordpress.com/...-own-for-free/
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To control flies: Fill plastic bags half full with water and add 4 pennies, zip shut and hang in the problem area.
The was observed to work by a group eating at Sweety Pie's restaurant. No flies at all were seen in the outdoor eating area.
Hope these help.........PS -- I love the Sweety Pies show on Oprah's network on Sun. evenings -- she is a interesting, smart lady and keeps everyone in line from relatives to employees.