Puncture Vine Weevils will provide long-term biological control once established. Look for Microlarinus lareynii for the seed and Microlarinus lypriformis for the stem.
There are 4 corner posts set and buried in the ground. The 2x4 frame supported the top during construction and was removed afterwards.
Full credit should be given to our volunteers who made it happen... specifically Matt Donaldson who spent the summer with us and now lives in Portland, OR.