Canada thistle control 8 to 12 months after post-harvest (late August to early October) herbicide application, NDSU and SDSU trials, 1990-99.  

        

Herbicide1

Canada thistle control2

 

 

Number of

trials

 

Trade name

Rate

Range

Average

 

 

pt/acre

%

 

2,4-D

2

24-78

43

4

 

4

         32-53

41

4

Banvel

2

43-89

67

7

 

4

86-90

88

2

Banvel + 2,4-D

1 + 2

27-46

35

4

Roundup

2

71-96

83

7

 

3

87-88

88

2

Roundup +

2,4-D

1 + 1.25

61-72

67

2

 

2 + 1

56-63

60

2

Fallowmaster

2.75

19-84

44

3

Roundup + Banvel

 

2 + 1

 

87-95

 

91

 

2

Curtail

2

39-68

55

8

 

4

50-79

68

7

Tordon + 2,4-D

1 + 2

59-95

80

3

Distinct

6 oz

63-67

65

2

1Adjuvants not listed.

2Several trials include tillage and crop competition after herbicide application to supplement control.

 

(October, 2000)