SPOKANE, Wash. (AP) — Harvesting the vast apple orchards of Washington state each year requires thousands of farmworkers, and many work illegally in the United States.

That system could eventually come to an end as at least two companies are rushing to get robotic fruit picking machines to market.

Members of the $7.5 billion annual Washington agriculture industry have long grappled with labor shortages, and depend on workers coming up from Mexico each year to harvest many crops.

Karen Lewis, a Washington State University cooperative extension agent who has studied the farm labor issue, said fruit picking machines will change the industry but it will be years before existing orchards can be converted to accommodate them.

Advocates for farm workers say replacing human workers with machines could lead to the loss of other jobs in local communities.