Topdressing High Shoot Density Putting Greens

Sand topdressing helps control/dilute organic matter accumulation on putting greens.  The popularity of high shoot density creeping bentgrass (ex. Penn “A4”, Alpha, etc.) and bermudagrass ultradwarf (ex. Tifeagle) varieties make the incorporation of topdressing into greens difficult.  The inability to incorporate can result in much of the topdressing being removed by mowing.  Additionally, mower blades loose their sharpness resulting in poor mowing quality.

 

In one study1 researchers studied the impact of rolling and brushing for incorporating sand topdressing into a ‘Tifeage’ putting green mowed at 4 mm.  Sand was applied every 2-weeks at 550 g m-2 (0.4-mm depth).  After application the treatments consisted of brushing and vibratory rolling alone or in combination.  The control was a non-topdressed area.  Two days after application clippings were collected and amount of sand determined.

 

Vibratory rolling alone resulted in removal of more than 10 percent of the applied sand.  Brushing alone resulted in 4 to 6 percent removal.  The combination of brushing and rolling was not significantly different than the non-topdressed control. 

 

In a previous study on Penn A and G series creeping bentgrass2 using a topdressing rate of 275 g m-2 found that only 1 to 3 percent of sand was removed by brushing alone.  For ultradwarf bermudagrass greens brushing alone or vibratory rolling alone could still lead to poor turf quality and mower damage.  The combination of brushing and then rolling is more effective at incorporating the sand.

 

Reference

1.  Kauffman, J.M., J.C. Sorochan, and J.T. Brosnan.  2011.  Brushing plus vibratory rolling enhances topdressing incorporation on ultradwarf bermudagrass putting greens.  Online.  Applied Turfgrass Science doi: 10.1094/ATS-2011-0126-03-RS

2.  Stier, J.C. and Hollman, A.B.  2003.  Cultivation and topdressing requirements for thatch management in A, G bentgrasses and creeping bluegrass (Poa annua var. reptans) HortScience 38:1227-1231.