Liberty-resistant Canola Herbicide Trial, Carrington, 2000.
B. Henson, G. Endres and J. Schneider

The experiment was conducted on a minimum-till field and Heimdahl-Emrick loam soil with 6.2 pH and 3.3% organic matter at the NDSU Carrington Research Extension Center. The experimental design was a randomized complete block with three replicates. Herbicide treatments were applied to 5 by 25 ft plots with a hand-boom or hooded bicycle–wheel plot sprayer. PPI treatments were applied at 18.4 gal/A at 35 psi through 8002 flat fan nozzles on May 1 with 69 F, 23% RH, 90% clear sky, and 8 mph wind on a dry soil surface and incorporated with a roto-tiller at a 3- to 4-inch depth. ‘InVigor 2573‘ canola was planted at 700,000 PLS/A on May 3 in 7-inch rows at a 0.5- to 1-inch depth.  POST treatments were applied at 9.2 gal/A at 35 psi through 8001 flat fan nozzles. POSTA treatments were applied on June 2 with 50 F, 77% RH, clear sky, and 8 mph wind to 3-leaf canola, 3- to 4-leaf foxtail, 1-inch tall to flowering wild mustard, and other annual broadleaf weeds were 1- to 3-inches tall. POSTB treatments were applied on June 16 with 51 F, 74% RH, 95% cloudy sky, and 11 mph wind to 6- to 8-leaf canola, 3- to 6-inch tall yellow and green foxtail, 6- to 15-inch tall common lambsquarters, 10- to 15-inch tall horseweed, 12-inch tall kochia, 1- to 4-inch tall redroot and prostrate pigweed, 6-inch tall Russian thistle, 2- to 15-inch tall wild buckwheat, and flowering wild mustard.

Visual crop injury was absent or negligible with all herbicide treatments (data not shown). Few differences in weed control were evident among herbicide treatments with the first and second visual evaluations (Table).

The third evaluation (canola at physiological maturity) indicated that control of all weed species present was good to excellent (84 to 99%) with treatments that included trifluralin (Table). Weed control generally was similar between application timings of glufosinate, but an advantage existed with early application of glufosinate for Russian thistle control. Sequential applications of glufosinate generally provided similar weed control as single applications. Glufosinate at 0.44 lb/A generally did not improve weed control compared to glufosinate at 0.36 lb/A.

Herbicide

 

Weed control

Treatment1

Rate

Timing

 

Fota2

Colq

Howe

KOCZ

Piwe3

Ruth

Wibw

Wimu

 

lb/A

 

 

_____________________________%_____________________________

Evaluation 1 (10 to 12 d after last POST herbicide application):

 

 

 

 

Untreated

 

 

 

0

0

0

0

0

0

0

0

Trif/Gluf

0.75/0.36

PPI/POSTA

 

99

99

99

99

99

99

99

97

Gluf/Gluf

0.26/0.26

POSTA/B

 

99

79

75

99

99

98

76

99

Qufp-P+Gluf

0.04+0.36

POSTA

 

83

75

91

91

95

90

81

90

Gluf

0.44

POSTB

 

93

73

75

99

99

93

81

99

Qufp-P+Gluf

0.03+0.36

POSTB

 

98

96

88

98

99

91

94

99

Seth+Gluf

0.04+0.36

POSTB

 

66

50

73

96

99

62

63

99

Trif/Seth

0.75/0.36

PPI/POSTA

 

91

97

98

98

99

95

99

57

Seth+Clpy

0.10+0.19

POSTB

 

96

35

88

98

98

0

68

98

LSD (0.05)

 

 

 

34

38

37

8

3

14

36

10

 

 

 

 

 

 

 

 

 

 

 

 

Evaluation 2 (26 to 28 d after last POST herbicide application):

 

 

 

 

Untreated

 

 

 

0

0

0

0

0

0

0

0

Trif/Gluf

0.75/0.36

PPI/POSTA

 

99

99

99

99

99

99

99

99

Gluf/Gluf

0.26/0.26

POSTA/B

 

99

79

75

99

99

98

76

99

Qufp-P+Gluf

0.04+0.36

POSTA

 

86

95

77

98

99

94

77

96

Gluf

0.44

POSTB

 

88

76

76

99

96

96

66

99

Qufp-P+Gluf

0.03+0.36

POSTB

 

96

91

86

86

98

94

88

99

Seth+Gluf

0.04+0.36

POSTB

 

89

40

60

79

99

79

62

99

Trif/Seth

0.75/0.36

PPI/POSTA

 

98

96

99

99

99

96

99

55

Seth+Clpy

0.10+0.19

POSTB

 

88

48

86

88

96

61

57

99

LSD (0.05)

 

 

 

18

31

34

26

4

23

31

29

 

 

 

 

 

 

 

 

 

 

 

 

Evaluation 3 (canola at physiological maturity):

 

 

 

 

 

 

Untreated

 

 

 

0

0

0

0

0

0

0

 

Trif/Gluf

0.75/0.36

PPI/POSTA

 

98

95

99

99

99

99

89

 

Gluf/Gluf

0.26/0.26

POSTA/B

 

85

83

72

89

95

92

68

 

Qufp-P+Gluf

0.04+0.36

POSTA

 

70

80

76

88

95

99

72

 

Gluf

0.44

POSTB

 

84

73

77

88

93

78

66

 

Qufp-P+Gluf

0.03+0.36

POSTB

 

84

94

92

99

94

84

80

 

Seth+Gluf

0.04+0.36

POSTB

 

79

66

55

77

97

67

58

 

Trif/Seth

0.75/0.36

PPI/POSTA

 

99

87

99

99

97

88

84

 

Seth+Clpy

0.10+0.19

POSTB

 

81

65

98

72

92

71

78

 

LSD (0.05)

 

 

 

13

13

32

18

8

11

13

 

1Glufosinate treatments include AMS at 3 lb/A; Sethoxydim treatments include MSO

(Scoil) at 2.5% v/v.

 

 

 

 

 

 

 

 

 

 

2Fota=yellow and green foxtail.

 

 

 

 

 

 

 

 

 

3Piwe=Redroot and prostrate pigweed.

 

 

 

 

 

 

 

 

NDSU Vice President,
Dean and Director for Agricultural Affairs
NDSU Extension Service ND Agricultural
Experiment Station
NDSU College of Agriculture NDSU College of Human Development and Education