Objective
To determine if a liquid ice melt material may be suitable to remove ice from golf course putting greens. Ice formation on putting greens in Iowa is a common occurrence. Freezing rain and melted snow followed by re-freezing can lead to an ice layer forming on the green nearly 2 inches thick. Some superintendents have tried to physically remove the ice layer from the green. Various commercial ice melt materials are available for non-turfgrass use.
Materials and Methods
A commercial liquid ice melting product, Select®, was screened for toxicity on creeping bentgrass during the winter months of 1999. Select®, a mixture of potassium acetate and water, was applied at various rates to creeping bentgrass plugs.
Plugs were cut from an established 'Crenshaw' creeping bentgrass area at the Iowa State University Horticulture Research Station north of Ames, IA in January. They were potted in sand medium and maintained outside from February until mid-March.
Two separate tests were run. In Test I, Select® was applied at 0, 2, 3, 4, 5, 6, and 7 gal/1000 ft2 on three dates (Table 1). In Test II, the deicer was applied at 0, 6, 9, 12, 15, 18, and 21 gal/1000 ft2 in one application. The deicer was diluted in water to a volume of 20 ml for ease of application using a hand sprayer. Three replications were conducted for each test.
Treatments for Test I were applied on February 17, February 22, and March 1. Decier was applied for Test II on February 22. On March 22, the bentgrass plugs were placed in the greenhouse and evaluated for greenup.
Percent green cover and visual quality data were taken beginning on March 24. Percent green cover was estimated as the area per pot covered by green bentgrass. Visual quality was assessed using a 9 to 1 scale with 9 = best and 1 = worst quality. Additional data were taken on March 29, April 1, April 4, April 9, and April 12.
Table 1. Application rates and timing for treatments in the 1999 SelectÒ Liquid Ice Melter Study.
|
|
|
(gal product/1000 ft2) |
|
|
|
Untreated control |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
|
|
Select® |
|
|
Table 2. Visual quality of creeping bentgrass treated in the 1999 SelectÒ Liquid Ice Melter Study.
|
|
|
(gal product/ 1000 ft2) |
|
|
|
1 |
5 |
9 |
12 |
|
|
|
Untreated control |
0.0 |
|
8.0 |
9.0 |
9.0 |
9.0 |
9.0 |
9.0 |
8.3 |
|
|
Select® |
2.0 |
|
7.7 |
9.0 |
8.0 |
8.0 |
8.0 |
8.0 |
8.6 |
|
|
Select® |
3.0 |
|
6.7 |
8.0 |
7.7 |
7.7 |
7.7 |
7.7 |
7.7 |
|
|
Select® |
4.0 |
|
5.7 |
7.3 |
7.3 |
7.3 |
7.3 |
7.3 |
7.3 |
|
|
Select® |
5.0 |
|
4.7 |
7.52 |
7.52 |
7.52 |
5.3 |
5.3 |
5.9 |
|
|
Select® |
6.0 |
|
5.3 |
7.52 |
6.3 |
6.3 |
7.0 |
7.0 |
5.8 |
|
|
Select® |
7.0 |
|
6.03 |
5.03 |
7.03 |
7.03 |
7.03 |
7.03 |
2.9 |
|
|
Select® |
6.0 |
|
8.0 |
9.0 |
8.0 |
8.0 |
8.0 |
8.0 |
8.7 |
|
|
Select® |
9.0 |
|
7.0 |
8.3 |
7.7 |
7.7 |
7.7 |
7.7 |
8.3 |
|
|
Select® |
12.0 |
|
5.3 |
7.3 |
7.0 |
7.0 |
7.0 |
7.0 |
7.0 |
|
|
Select® |
15.0 |
|
3.02 |
6.52 |
6.0 |
6.0 |
6.0 |
6.0 |
5.4 |
|
|
Select® |
18.0 |
|
6.02 |
6.02 |
6.52 |
6.52 |
6.52 |
4.7 |
5.3 |
|
|
Select® |
21.0 |
|
6.03 |
6.03 |
6.03 |
6.03 |
3.52 |
3.52 |
2.7 |
|
|
LSD0.05 |
|
|
2.2 |
2.3 |
2.2 |
2.4 |
2.4 |
|
2.8 |
1Visual quality was assessed using a 9 to 1 scale with 9 = best, 6 = lowest acceptable, and 1 = worst quality.
2This value represents only two replications - there was no bentgrass in the third replication.
3This value represents only one replications - there was no bentgrass in the other two replications.
Table 3. Percentage green cover of creeping bentgrass treated in the 1999 SelectÒ Liquid Ice Melter Study.
|
|
|
(gal product/ 1000 ft2) |
|
|
|
1 |
5 |
9 |
12 |
|
|
|
Untreated control |
|
|
66.7 |
100.0 |
100.0 |
100.0 |
100.0 |
100.0 |
94.4 |
|
|
Select® |
|
|
46.7 |
78.3 |
80.0 |
86.7 |
86.7 |
86.7 |
77.5 |
|
|
Select® |
|
|
7.0 |
15.0 |
15.0 |
18.3 |
23.3 |
28.3 |
17.8 |
|
|
Select® |
|
|
2.7 |
11.7 |
11.7 |
15.0 |
20.0 |
23.3 |
14.1 |
|
|
Select® |
|
|
4.7 |
5.7 |
5.7 |
11.7 |
12.0 |
13.7 |
8.9 |
|
|
Select® |
|
|
2.7 |
5.0 |
5.3 |
7.0 |
6.7 |
8.3 |
5.8 |
|
|
Select® |
|
|
0.7 |
1.7 |
1.7 |
1.7 |
1.7 |
1.7 |
1.5 |
|
|
Select® |
|
|
28.3 |
60.0 |
68.3 |
76.7 |
78.3 |
83.3 |
65.8 |
|
|
Select® |
|
|
16.7 |
40.0 |
45.0 |
56.7 |
61.7 |
65.0 |
47.5 |
|
|
Select® |
|
|
11.7 |
18.3 |
18.3 |
25.0 |
25.0 |
20.0 |
19.7 |
|
|
Select® |
|
|
1.3 |
2.0 |
4.0 |
5.7 |
5.3 |
7.0 |
4.2 |
|
|
Select® |
|
|
4.0 |
8.3 |
10.0 |
13.3 |
13.3 |
25.0 |
12.3 |
|
|
Select® |
|
|
0.3 |
0.0 |
0.3 |
0.0 |
0.7 |
0.7 |
0.3 |
|
|
LSD0.05 |
|
|
11.5 |
16.3 |
17.6 |
18.1 |
18.5 |
20.2 |
15.1 |
1These values represent the percentage of area per plot covered by green bentgrass.
Results
These results are preliminary and the products mentioned in this report should not be used at this time for removing ice from golf course turf.
Phytotoxicity caused by Select® was rate
dependent. A single application of Select® at
6 gal/1000 sq. ft. resulted in some initial phytotoxicity,
but turf recovered to an acceptable level within 1.5 months.
At 9 to 12 gal/1000 sq. ft., injury was greater and recovery
slower. Lower application rates applied more frequently
reduced injury compared to single applications applied at an
equal rate. Since golf course putting greens are highly
scrutinized, this product should be investigated at rates
lower than 2.0 gal/1000 sq. ft.
 |
ISU Horticulture:Publications:1999 Turfgrass Report | College of Agriculture |