who we are

Through a combined 50  years in golf course management, co-founders, Mark Jull and Casey O'Connor have learned that golf course superintendents have a tough job. High performance turf nutrition is a critical strategy in resolving the challenges inherent with providing high quality turf surfaces.

In order to deliver the level of service and solutions expected, Mr. O'Connor and Mr. Jull joined forces with Residex LLC. Residex is a Michigan-based independent distributor of professional pest control and turfgrass management supplies. In business since 1946, Residex today serves the eastern half of the US from 25 warehouse locations across 14 states. Residex includes a strong product development team comprised of PhDs, chemists, former golf course superintendents and seasoned business professionals.

Plant Health Division was purchased by Target Specialty Products of Santa Fe Springs, California in 2016 as part of an acquisition that included Residex in the Eastern USA and Turfgrass Canada in Eastern Canada.  Today Target Specialty Products includes 42 locations in the US plus Canada, and includes over 180 associates across North America.

Plant Health Division began by sourcing the most complete, accurate laboratory services available.  Secondly, Plant Health Division has partnered with companies who manufacture the finest nutritional, seed and plant protectant  products in the world.


gregor kowalski

Vancouver Island Turfgrass Nutritionist

Gregor was raised with a strong background in Agriculture and a love for the game of golf. Gregor enrolled in the Turf Grass Management Program at Fairview College in 1989. He received a diploma 2 years later and is now entering his 25th season in Golf Course Operations, 21 of them as Head Superintendent and 18 of those at Royal Oak Golf Club in Victoria, BC.

In 2007, Gregor founded the Vancouver Island Superintendent’s Association Multiple Sclerosis fundraising event. Over the past 8 years, with the help and leadership of many of his fellow Superintendents and Industry Representatives, it has now grown to become a two part event comprised of an Industry Continuing Education Seminar and Fundraiser as well as a Public Gala Banquet and Dance which has raised close to $800,000 since inception. 


Superintendent: Royal Oak Golf Club - Victoria, BC

Founder: Vancouver Island Superintendent's Association MS Fundraiser

Superintendent of the Year: British Columbia Golf Superintendents Association

Turfgrass Management Diploma: Fairview College



Mark Jull BSc (AGR)

Sales Manager

Mark has worked in golf course management since the age of 15, where he immediately knew his vision was to develop a career focused on agronomy and turf management.  Mr. Jull worked at some of Canada's premier golf courses as Assistant Superintendent. In 2006 Mr. Jull decided to specialize his career on his true passion which is plant physiology, agronomy and soil science.  At this time Mr. Jull began developing a strong reputation in Alberta as a technical resource to Superintendents.


Certified Field Representative: International Sports Turf Research Center (ISTRC) Lenexa Kansas

Regional Manager: TURF Canada Inc. -  Alberta

Assistant Superintendent: Devils Pulpit Golf Association - Caledon, Ontario

Assistant Superintendent: Rosedale Golf Club - Toronto, Ontario

B.Sc (Agr.) - University of Guelph, Ontario

Certificate in Turfgrass Management - Penn State University World Campus





Northern Alberta Turfgrass Nutritionist

At the age of 16, Eric entered the Turf Industry in southern Ontario. Through his tenure in golf, Eric has worked at The Mandarin GCC, Banff Springs GC, Furry Creek GC, Kananaskis GC, Country Hills GCC, and Capilano GCC.  Through these experiences Eric developed an understanding of advanced agronomic and maintenance practices.  It was during these years Eric attended school at Seneca College for Environmental Landscape Management and University of Guelph for Turfgrass Management. 

As Eric’s career developed, it became clear that fertility in golf was his passion.  At Country Hills GCC and Capilano GCC his focus was in fertility management and program development.  Having experienced different management techniques and products, Eric fully understood product lines and their applications. 


Assistant Superintendent: Capilano Golf and Country Club

Assistant Superintendent:  Country Hills Golf and Country Club

Environmental Landscape Management Diploma - Seneca College

Turfgrass Management Diploma - University of Guelph