Page 22 - Transitioning Turfgrass

TRANSITIONING TURFGRASS

Untreated

Ammonium sulfate
(13-2-13)
Seablend
No Roll
Polyon Roll 4X/wk

Urea
Ammonium sulfate
(21-0-0)
0 12.5 25 37.5 50 62.5

Figure 1 Effect of fairway rolling and various fertilizers on dollar spot uppression (rating on July, 2016) at Star Hue CC, Korea.

Turfgrass Association (NYSTA) and New En- fertilizers and fairway rolling using Tru Turf
gland Regional Turfgrass Foundation (NERTF) FR-108 rolling heads on dollar spot control.
in 2015 to examine the practice of rolling using
a Smithco Fairway Ultra 10 Roller and confirm
its potential to reduce fairway fungicide applica- Materials and Methods
tions for dollar spot while also determining proper
rolling frequencies and exploring interactions with Field efficacy testing was conducted at Sappo-
bio-control products and nitrogen fertilizers. In ro Golf Club Yuni Course, Hokkaido, Japan and
brief, in comparison to non-rolled plots, increased The Star Hue Country Club, Yangpyeong, Korea.
fairway rolling frequencies at 3X, 4X and 6X per The trial was conducted on perennial ryegrass at
week increased dollar spot reduction by 40-60%, Sapporo GC Yuni and on Kentucky bluegrass at
with a positive correlation between reduced clip- Star Hue CC. Rolling began at each course in mid-
ping yields and increased rolling frequency. Addi- May, 2016 and was applied Tuesdays and Thurs-
tionally, a substantial reduction in dollar spot was days as a double roll for a total of 4 rolling passes
observed while rolling (4 times per week, Tuesday over the experimental plots each week using a Tru
and Thursday, double roll) and applying 0.20 lb Turf FR-108 rolling head mounted on Jacobson
nitrogen/1,000 ft2 every 14 days. Yet, there are fairway mowers (Photo 1, page 17). Fertilizer treat-
still more questions on whether dollar spot reduc- ments were applied on May 19, July 7 and August
tion by fairway rolling is affected by different turf- 10 at Sapporo GC and May 24, June 14 and July
grass species or different rolling machines. 5 at Star Hue CC. Urea (46-0-0), ammonium
Therefore, the main objectives of the 2017 study sulfate (13-2-13 and 21-0-0), organic fertilizer (Se-
were: ablend, 12-0-12) was applied at 1.22 g/m on all
2
* determine the effect of fairway rolling using application dates (Fig. 1). Polyon (polymer coated
Tru Turf FR-108 rolling heads to control dol- urea, 41-0-0) was applied at 7.32 g/m once on
2
lar spot on Kentucky bluegrass and perennial the first application date at both locations.
ryegrass fairways on golf courses. Field trial plots were arranged in a randomized
* determine the interactive effect of common complete block design, with four replications. Plot

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