View Full Table | Close Full ViewTable 1.

Soil physical properties of the growth media and topdressing sand used on an established ‘A-1’ creeping bentgrass golf green.

 
Soil separation, % Sieve fraction sand particle diameter, % retained
Sand 1–0.05 Silt 0.05–0.002 Clay <0.002 Gravel 2 V. Coarse 1 Coarse 0.5 Medium 0.25 Fine 0.15 V. Fine 0.05 Bulk density Hydraulic conductivity Total porosity Organic matter
mm g cm−3 cm h−1 % g kg−1
99 0.4 0.1 0.0 0.0 25 68 6.0 1.1 1.46 17 45 14



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Timing, depth, diameter, and spacing of thatch management treatments used on an established ‘A-1’ creeping bentgrass golf green. 2001–2002.

 
Treatment† Timing Depth Diameter–width Spacing
mm
Untreated
Topdressing (factor 1 with 2 levels)
 Twice monthly March–October 0.6
 Monthly March–October 1.2
Mechanical–biological (factor 2 with 9 levels)
 None (topdressing only)
 Vertical mowed twice annually (V) March and October 19 2 25
 Vertical mowed four times annually March, May, September, October 6.4 2 25
 Core cultivation four times annually (C) March, May, June, September 76 6.4 and 15.8‡ 76
 Grooming twice weekly (G) April–September 3
 Biological thatch control agent May and July
 C+G combination
 C+V combination
 C+V+G combination
Topdressing was used with all single and combination mechanical and biological treatments.
Core diameter was 6.4 mm in May and June and 15.8 mm in March and September.



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Thatch–mat depth, surface hardness, and water infiltration rates for thatch management treatments used on an established ‘A-1’ creeping bentgrass golf green, 2001–2002.

 
Treatment Thatch–mat depth† Surface hardness‡ Water infiltration‡
mm g max cm h−1
Untreated 32.4 81 61
Topdressing only 37.1 76 73
Vertical mowed twice annually at 19.1 mm depth (V) 34.7 81 102
Vertical mowed four times annually at 6.4 mm depth 34.7 80 86
Grooming twice weekly (G) 34.6 79 72
Core cultivation four times annually (C) 33.3 74 157
Biological thatch control agent 36.4 79 72
C+G 34.1 73 140
C+V 33.2 73 164
C+G+V 32.8 74 149
LSD (0.05) 2.7 6.0 20
Measurements obtained in December of 2002 and averaged across topdressing levels.
Measurements obtained monthly from March to October each year and are averaged across sampling dates, topdressing levels, and years.



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Organic matter concentration by weight for thatch management treatments used on an established ‘A-1’ creeping bentgrass golf green, 2001–2002.

 
Organic matter†
Treatment Initial Final Change Reduction or increase
g kg−1 %
Untreated 19 25 +6* +32
Topdressing only 21 20 −1 −5
Vertical mowed twice annually at 19.1 mm depth (V) 20 18 −2 −10
Vertical mowed four times annually at 6.4 mm depth 20 18 −2 −10
Grooming twice weekly (G) 19 21 +2 +11
Core cultivation four times annually (C) 20 18 −2 −10
Biological thatch control agent 23 20 −3 −13
C+G 21 19 −2 −10
C+V 19 16 −3 −16
C+G+V 21 17 −4* −19
LSD (0.10) 3.4
* Change significantly different from zero (P < 0.10).
Measurements are averaged across topdressing levels. Initial denotes measurements obtained before treatment application; Final denotes measurements obtained in December, 2002; and Change = Final- Initial.



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Turfgrass quality for thatch management treatments used on an established ‘A-1’ creeping bentgrass golf green, 2001.

 
Treatment March April May June July August September October
1–10†
Untreated 10.0 10.0 9.8 10.0 10.0 9.5 9.3 9.7
Topdressing only 9.1 9.1 9.7 10.0 10.0 10.0 10.0 10.0
Vertical mowed twice annually at 19.1 mm depth (V) 9.4 9.4 9.7 10.0 10.0 10.0 10.0 10.0
Vertical mowed four times annually at 6.4 mm depth 9.4 9.5 9.7 9.9 10.0 10.0 9.8 9.9
Grooming twice weekly (G) 9.3 9.4 9.7 10.0 9.9 9.9 9.6 9.7
Core cultivation four times annually (C) 9.0 9.4 9.7 9.1 9.2 9.3 9.5 9.3
Biological thatch control agent 9.7 9.7 9.8 10.0 10.0 10.0 10.0 9.9
C+G 9.3 9.3 9.8 9.1 9.1 9.3 9.0 8.9
C+V 9.1 9.1 9.7 9.2 9.2 9.2 9.8 9.3
C+G+V 9.2 9.0 9.6 9.0 8.9 9.2 9.3 9.0
LSD (0.05) NS NS NS 0.21 0.19 0.51 0.61 0.33
Turfgrass quality ratings on 1–10 scale with 1 = no live turfgrass and 10 = dark green, dense uniform turfgrass. Ratings are averaged across topdressing levels.



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Turfgrass quality for thatch management treatments used on an established ‘A-1’ creeping bentgrass golf green, 2002.

 
Treatment March April May June July August September October
1–10†
Untreated 9.8 10.0 9.7 10.0 10.0 7.2 6.4 7.1
Topdressing only 9.2 9.0 9.7 10.0 10.0 9.6 9.5 9.5
Vertical mowed twice annually at 19.1 mm depth (V) 9.6 9.4 9.7 10.0 10.0 9.5 9.5 9.5
Vertical mowed four times annually at 6.4 mm depth 9.5 9.5 9.7 9.7 9.9 9.8 9.4 9.7
Grooming twice weekly (G) 9.4 9.3 9.7 10.0 9.9 8.7 8.7 8.7
Core cultivation four times annually (C) 9.7 9.3 9.7 9.0 9.0 8.7 8.8 8.7
Biological thatch control agent 9.2 9.7 9.9 10.0 10.0 9.4 9.5 9.5
C+G 9.0 9.3 9.8 9.0 8.8 8.7 8.8 8.4
C+V 9.0 9.0 9.6 9.1 8.7 9.0 9.0 8.5
C+G+V 9.3 9.0 9.5 9.0 8.5 8.7 9.0 8.5
LSD (0.05) NS NS NS 0.09 0.25 0.98 1.22 0.91
Turfgrass quality ratings on 1–10 scale with 1 = no live turfgrass and 10 = dark green, dense uniform turfgrass. Ratings are averaged across topdressing levels.



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Ball roll distance 7, 14, and 21 d after treatment (DAT) for selected thatch management treatments used on an established ‘A-1’creeping bentgrass golf green, 2001–2002.†

 
Treatment 7 DAT 14 DAT 21 DAT
cm
Topdressing only 151 154 155
Vertical mowed two times annually at 19.1 mm depth 142 156 154
Core cultivation four times annually 139 146 147
LSD (0.05) 7 8 NS
Measurements are averaged across sampling dates, topdressing levels, and years.