Study: Efficacy of Herbicides in Buckbrush Control
Buckbrush (Symphoricarpos orbiculatus) is a perennial weed commonly found in pastures and rangeland in northeast Nebraska (Figure 1). It often occurs in heavy stands, which can reduce desirable plant species by as much as 84%. Buckbrush also can significantly deplete soil water to the detriment of pasture grasses, particularly in dry conditions.
In 2016 and 2017 we compared the effectiveness of seven herbicides for control of buckbrush. Herbicides were sprayed in early June, when Buckbrush had 2-4 feet of green growth. The evaluated herbicides were:
- 2,4-D LV ester® (2,4-D ester [3 qts/acre]),
- Curtail®/Cody® (clopyralid + 2,4-D [3 pts/acre]),
- Perspective® (aminocyclopyrachlor + chlorsulfuron [8 oz/acre]),
- Cimmaron Plus® (metsulfuron-methyl + chlorsulfuron [0.5 oz/acre]),
- Grazon P+D® (picloram + 2,4-D amine [4 pts/acre]),
- Milestone® (aminopyralid + triclopyr [7 oz/acre]), and
- Chaparral® (aminopyralid + metsulfuron-methyl [1.25 oz/acre]).
Perspective® provided the best control (80-83%) of buckbrush, and the control lasted over one year (Table 1). Cimmaron plus®, 2,4-D LV ester® and Grazon P+D® provided 75-98% control, but it only lasted for one season (90 days after spray). Chaparral® and Curtail®/Cody® provided fair control (62-66%) that lasted for one season. Milestone provided poor control of buckbrush.
These results indicated that a single application of only one herbicide provided buckbrush control for slightly more than a year. This two-year study suggests that repeated applications of Perspective®, Cimmaron plus®, 2,4-D LV ester® and Grazon P+D® are needed to achieve complete control of buckbrush. A multi-year study is needed to confirm this hypothesis.
|2,4-D LV ester®||3 qts||60||98||50|
|Cimmaron Plus®||0.5 oz||66||75||27|
|Grazon P+D®||4 pts||53||80||23|
|a Days after treatment.|