David Doherty is the President and Founder of the “International Sports Turf Research Center, Inc.” (ISTRC). and holds three patents on the ISTRC System which was developed to monitor the ageing process of both sand and soil based golf greens. Mr. Doherty is recognized by most in the industry to be the world’s foremost authority on the Physical Properties of golf greens. The majority of the top 100 courses in all categories use the ISTRC System to monitor the effectiveness of their agronomic programs from year to year or from season to season. ISTRC has monitored the effects of aerification and other cultural practices of over 1500 different golf courses and thousands of greens in less than 10 years. The patented ISTRC System of undisturbed core testing was developed by Mr. Doherty to provide turf grass professionals with: (a) accurate, cost effective data about root zone conditions as they exist in the field, and (b) the effects of those conditions on turf quality and plant health. ISTRC’s unique and proprietary data base contains thousands of test results. The knowledge derived from the database allows ISTRC to not only report the test data, but also interpret the data in “layman’s language”.