"Sunflower Seed Production" print (1972)

I'm always a fan of the super-real in conceptual commercial art, and here we have a ring of carefully-drawn sunflower petals surrounding a circle of not just sunflower seeds, but a pile of harvested sunflower seeds. The illustration bends time from living crop to finished product, all the while maintaining the wholeness of the plant. I can't explain the "X" drawn over the seeds, though. Any ideas? 

A booklet cover reproduction available at 12x18" or 24x36" on Epson Enhanced Matte 192 gsm paper printed with Epson UltraChrome XD2 archival ink. Sold in an open edition, unframed. The Canada Department of Agriculture wordmark on this cover has been replaced with the words ”National Farming Forum” due to Section 9 of the Canadian Trademarks Act.