The Davey Tree Expert Co. of Kent is the fourth-largest 100 percent employee-owned company in the United States in a new National Center for Employee Ownership ranking.


The rankings are based on number of employees; Davey has 7,400 throughout North America, including 500 in Northeast Ohio.


“Employee ownership at Davey has been a tradition for more than 30 years, and it is an essential piece of our company’s success,” said Karl Warnke, chairman, president and chief executive of the tree, shrub and lawn-care company.


The company formulated an Employee Stock Ownership Plan (ESOP) in 1979, nearly 100 years after the business was founded by John Davey in 1880.


Earlier this year, Davey reported record earnings of $646 million for 2011, up from $591.7 million in 2010.


The company has been on a growth spurt, merging with or acquiring more than 30 companies since 2003.


The National Center for Employee Ownership ranking includes the nation’s largest companies that are at least 50 percent owned by an Employee Stock Ownership Plan or other broad-based employee-ownership plan.


Davey ranks 18th among all companies with at least 50 percent employee ownership.


Publix Supermarkets of Lakeland, Fla., with 152,000 employees, is the highest ranking company that is at least 50 percent employee-owned.


WinCo Foods of Boise, Idaho, with 14,000 employees is the largest 100 percent employee-owned enterprise on the list.