Alpharetta, Ga.-based John Deere Landscapes has named Doug Black as chief executive officer.

Black, whose new position becomes effective immediately, is former president and chief operating officer of Atlanta-based building materials manufacturer Oldcastle Inc.

JDL said Black will replace David Werning, who will serve as a JDL adviser until his retirement at the end of the year.

The company, once a part of farm equipment maker Deere & Co., is a supplier of wholesale irrigation, landscape lighting, nursery, and turf and maintenance supplies for green industry contractors.

Last fall, the New York investment firm Clayton, Dubilier & Rice acquired JDL in a deal valued at $465 million, but Deere & Co. retains a 40 percent stake.

JDL has annual revenue of more than $1 billion and about 2,000 employees.

Clayton, Dubilier & Rice’s holdings also include Hertz car rental, Culligan water treatment supplies, Sally Beauty supplies and retail and ServiceMaster, whose brands include Merry Maids, Terminix pest control and TruGreen lawn service.