Trivia Ticket Tuesday - Win 2 Tickets to the Mother Earth News Fair!

http://www.motherearthnews.com/nature-and-environment/trivia-ticket-tuesday-win-2-tickets-to-the-mother-earth-news-fair.aspx

Here's how it works: 

Comment on this post with your answer to today's trivia question no later than 48 hours after the time stamp on the post. (It's right underneath the title.) We'll randomly select a winner from the correct answers, then send the winner two tickets to the Seven Springs, Pa. Mother Earth News Fair! Are you ready? Here goes...

Who writes most of the gardening articles for Mother Earth News?