Thanks, you guys! That is the "turkey tracks" aka "crows foot" stitch that Sara Vincent taught us here
http://www.quiltingboard.com/posts/list/1753.page
back on the 6th of August. JUST in the nick of time! I needed to stabilize that big house and the big tree and that was the very stitch I needed.
The center block is 36 inches square.
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