The Maine-based company says some styles are on back order until February. The company is in the process of hiring 100 workers and purchasing new equipment to double its capacity for making the boots' traditional rubber soles.
Sales have grown from fewer than 100,000 a decade ago to about 450,000 this year.
Spokeswoman Carolyn Beem says there are currently 60,000 back orders for boots, and that could grow to 100,000 by month's end. The company's stitching operation in Brunswick will go 24-7 this weekend in hopes of catching up.
She says the company is happy with the surging demand but sorry to disappoint customers.