1998 Iowa Turfgrass Research Report


1998 Iowa Turfgrass Research Report

Effect of Beacon on the Germination of Kentucky Bluegrass and Creeping Bentgrass

Barbara R. Bingaman, Nick E. Christians, and Michael B. Faust

The objective of this study was to evaluate the effect of CGA #136872 (Beacon) on seed germination and establishment of Kentucky bluegrass and creeping bentgrass. This study was conducted at the Iowa State University Horticulture Research Station located north of Ames, IA. The experimental plot was a bare soil area that had been tilled, raked, and prepared for seeding. The soil in this plot was a Nicollet (fine-loamy, mixed, mesic Aquic Hapludoll) with an organic matter content of 3.9%, a pH of 7.0, 3 ppm P, and 76 ppm K.

Individual plot size was 5 x 6 ft. There were three replications with 3 ft barrier rows between replications. CGA #136872 (Beacon) was applied at 20 and 40 g product/acre. Applications were made eight, four, and two weeks, and one day before seeding. The liquid materials were applied at 30 psi using a CO2 backpack sprayer equipped with TeeJet ™ #8006 flat fan nozzles. A methylated seed oil spreader (SCOIL MSO) was added at 0.25% V/V to all treatments except the control. CGA #136872 (Beacon) was mixed in 283 ml of water per plot which translates to an application rate of 3 gal/1000 ft2.

The 'eight weeks before seeding' treatments were applied on July 14, the 'four weeks before seeding' on August 15, the 'two weeks before seeding' on August 28, and the 'one day before seeding' on September 11. Seeding took place on September 12.

There was a heavy infestation of weeds in the plots and border rows at the time of seeding. All weeds were cut off with a hoe and removed. The soil from individual plots was not mixed with adjacent plots. Light raking was performed to make shallow grooves in the soil for the seeds. The plots were split into two 5 x 3 ft subplots. One of these was seeded with 'Penneagle' creeping bentgrass at 1 lb/1000 ft2 and the other with 'Award' Kentucky bluegrass at 1.5 lb/1000 ft2. The seeding was done using a drop seeder. The plots were lightly raked following seeding to partially cover the seeds. Rainfall was sporadic during this period so the plot was irrigated daily.

Bentgrass seedlings were first observed on September 18. Kentucky bluegrass germination was noted on September 26. By October 2, differences in bentgrass cover were beginning to appear but the plants were so small that data were not taken. Germination was determined as the percentage of area per plot covered by each species. Percentage cover data were taken on October 9, October 14, and November 11 (Tables 1 and 2). Final 1997 data for this study were taken on November 11 because winter weather conditions had already set in. At this time, the bentgrass plants had matured but the bluegrass plants were still quite small.

Data were analyzed with the Statistical Analysis System (SAS, version 6.10) and the Analysis of Variance (ANOVA) procedure. Means were compared with Fisher's Least Significant Difference (LSD) test.

There were observable reductions in percentage cover of creeping bentgrass on October 9 and 14 even though the differences were not significant. The November 11 data show that the 'one day before seeding' treatment of CGA #136872 (Beacon) at 40 g product/A significantly reduced the percentage cover of bentgrass when compared with the untreated control. Although the 'one day before seeding' treatment of CGA #136872 (Beacon) at 20 g product/A did numerically reduce the bentgrass cover, the percentage cover was not significantly reduced from the untreated control (Table 1).

Because of the weather conditions in October, the bluegrass did not mature. The plants were still quite small when the final data were taken. There were significant differences (P „ 0.06) in bluegrass cover on November 11. The percentage cover of bluegrass treated with 20.0 g product/A at eight weeks, two weeks, and one day before seeding was significantly reduced when compared with the untreated control. In addition, significant reductions were recorded for bluegrass treated two weeks before seeding at 40 g product/A (Table 2). These were unusual results for the Kentucky bluegrass and observations will be made in the spring to confirm these results.

 

Table 1. Percentage cover1 of 'Penneagle' creeping bentgrass in the 1997 carryover seedling study.

 

Material
Rate product/A.
Timing of application (before seeding)
Oct 9
Oct 14
Nov 11
Mean cover

 

 

 

%
1

Untreated Control

NA
NA

32

35

55

41

2

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
8 weeks

40

45

73

53

3

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
4 weeks

43

43

75

54

4

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
2 weeks

30

32

72

44

5

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
1 day

22

27

40

29

6

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
8 weeks

33

35

65

44

7

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
4 weeks

20

20

45

28

8

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
2 weeks

20

23

53

32

9

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
1 day

5

5

12

7

 

LSD0.05

 

 

NS
NS
38
NS

1Percentage cover was estimated as the area per plot covered by creeping bentgrass.

'Eight weeks before seeding' materials were applied on July 14, 'four weeks' on August 15, 'two weeks' on August 28, and one day on September 11. Seeding took place on September 12.

NS = means are not significantly different at the 0.05 level.

 

Table 2. Percentage cover1 of 'Award' Kentucky bluegrass in the 1997 carryover seedling study.

 

Material
Rate product/A.
Timing of application (before seeding)
Oct 9
Oct 14
Nov 11
Mean cover

 

 

 

 

%
1

Untreated Control

NA
NA
13
15
53
27
2

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
8 weeks
12
17
32
20
3

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
4 weeks
17
18
48
28
4

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
2 weeks
12
15
25
17
5

CGA #136872 + SCOIL MSO

20.0 g + 0.25% V/V
1 day
12
12
35
19
6

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
8 weeks
15
17
50
27
7

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
4 weeks
12
15
40
22
8

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
2 weeks
12
15
35
21
9

CGA #136872 + SCOIL MSO

40.0 g + 0.25% V/V
1 day
10
10
40
20

 

 

 

 

 

(p „ 0.06)

 

LSD0.05

 

 

NS
NS
18
NS

1Percentage cover was estimated as the area per plot covered by Kentucky bluegrass.

'Eight weeks before seeding' materials were applied on July 14, 'four weeks' on August 15, 'two weeks' on August 28, and one day on September 11. Seeding took place on September 12.

NS = means are not significantly different at the 0.05 level.

Iowa State University ISU Horticulture:Publications:1998 Turfgrass Report College of Agriculture