About Us Lingruen Associates was founded in 1951 by Donald Lingruen. Don was eventually joined in the business by Joe Twehous. As the company grew, several new employees were added which included Paul Armstrong in 1974 and David Hoska in 1978. Both started in the position of helper, carpenter and eventually becoming licensed Branch 3 Inspectors. In 1982 Don and Joe decided it was time to retire and David and Paul obtained their interest in the business. By this time David had become licensed as the Branch 3 Operator for the company and assumed the position of President-CEO of the corporation. The Lingruen name was kept as it had become known throughout the area as a company with a good reputation and high quality of workmanship. In 1997 Gary Flowers  joined the company as Vice-President - CFO. Gary had been a licensed Branch 3 inspector for years in the area and obtained his Branch 3 Operator's license in 1991.  Not only did he bring years of valuable knowledge in the pest control industry but also had vast experience in construction. Francisco Rigoberto (Rigo) Rangel  started with Lingruen in 1990 as a carpenter's helper and continued to advance in the company until 2000 when he was promoted to General Foreman.  Rigo become a Vice-President - COO. in June of 2004.  He is also a licensed General Contractor and Branch 3 Field Rep. Lingruen's carpenters are all union members of the Carpenters Local Union #2236 and range in seniority from 5 years up to 34 years with the company. Our executive staff is involved in the Pest Control Operators of California.