Farmers grew more than 78,000 acres of legal hemp last year, the advocacy group VoteHemp reported. In 2017, they grew about 26,000 acres and in 2016, the total was less than 10,000 acres.
https://news.weedmaps.com/2019/02/report-u-s-grew-78000-acres-of-hemp-in-2018-tripling-2017-output/