Evaluation of the effectiveness of core aerification and/or topdressing by computer simulation.

Golf course superintendents and sport turf managers use core aerification and/or topdressing routinely to manage thatch problems and to alleviate soil compaction. A turf manager may not only be interested in the total impacted areas, but also in the sand percentage in certain depth of soil profile. The results of core aerification and topdressing are affected by many factors such as tine diameter, tine length and spacing, sand content in the original soil, and root zone depth. The objective of this study is to use computer modeling to simulate the results of core arification and topdressing operations under various conditions. There are eight different scenarios from various combinations of topdressing and aerification with or without core-removing. Of the eight combinations, five are realistic. Java language was used in writing the program to simulate different scenarios as individual cases or intermittent cases and to calculate total coring and topdressing times, amount of sand needed, areas impacted to reach a goal. Tine diameters used in the simulation range from 4.76 mm to 31.75 mm, tine length from 63.5 mm to 304.8 mm, and tine space from 25.4 mm to 152.4 mm. Although increasing the core diameter or decreasing the tine spacing both affect the impacted area at the power of two, the ultimate result is dictated by the topdressing thickness and the targeted sand percentage at a certain depth of the field. The model can be used to predict the sand content in a given volume of soil for various combinations of aerification and topdressing practices. Currently the predictive program can be used to simulate different scenarios to assist in developing cultivation and topdressing strategies. The program can also be used as an educational classroom model. However, the degree of mixing or spatial arrangement of the sand, silt, and clay has not been determined in this predictive model. Further research is also needed to correlate predicted results with actual field techniques using various types of cultivation equipment and topdressing practices.