Tech Notes Issue 6

Can a Coring Program Enhance Autumn Turf Recovery?

Coring is done to reduce soil compaction, improve soil oxygen levels, and reduce organic matter. Commonly, large tine coring is done in the spring with smaller tine coring done periodically through the summer (on approximately 3 week interval). A recent study confirmed at least from a plant carbohydrate perspective the advantage to this type of coring program1.

In a field study on a 'Providence' creeping bentgrass green, researchers at the University of Maryland compared a single spring coring with a 1.27 cm (0.5 inch) diameter hollow tine, alone and in combination with periodic summer quadra-tine (0.64 cm (0.25 inch diameter)
coring on plant photosynthesis, respiration, and carbohydrate levels.

Measuring carbohydrate levels over two seasons, the authors (principal investigator Dr. Peter Dernoeden) found the highest overall total TNC levels in creeping bentgrass occurred in spring (Table 1). From a management perspective these higher levels would promote
turf recovery from the more aggressive spring coring with the larger diameter tines. Lower TNC levels were found in the summer across all treatments. This would justify the smaller quadra-tine coring, which according to the study would have a lesser negative impact on summer turf recovery than the use of larger tines.

The authors reported higher TNC levels at the end of the season with the spring and summer coring treatment. They hypothesized this would enable plants to recover more quickly from summer stress. If this past spring you cored and then followed it with timely quadra-tining, your turf is set for a quicker recovery from this past summer's stress.

Reference:
1. Fu, J. and P.H. Dernoeden. 2009. Carbohydrate level, photosynthesis, and respiration in creeping bnetgrass as influenced by spring, and summer coring. 
J.Amer.Soc.Hort.Sci. 134:41-47.

Table 1: Selected data from Fu and Dernoeden (2009). TNC = total nonstructural carbohydrates, SPC—spring coring, SPC + SUC = spring coring + summer coring, NC = non-cored control. Means followed by the same letter are not significantly different. Table created from selected 2007 data.