The U.S. Environmental Protection Agency (EPA) a Section 3 Supplemental Label for use of the herbicide Matrix SG 25% WDG (rimsulfuron) for use on blueberries, raspberries and blackberries. This label will be in effect through March 31, 2020.
Matrix may be applied to these crops at 4 oz product per acre. It may be applied pre-emergence or early post-emergence to the weeds. If weeds are present at application, add non-ionic surfactant at 0.25%to the tank mix. Matrix is most effective if moved into the soil (activated) by 0.5-inch rainfall.
On highbush blueberries, apply Matrix to bushes established at least one year. Apply in a strip on each side of the row, avoiding contact with green blueberry leaves or stems. Matrix is moderately soluble and should not be used on soils classified as sands to avoid leaching into the bush root zone. Do not exceed 4 ounces product per acre per year. If Matrix is applied in a band of 50 percent or less of the total area, a second application may be made each year. Matrix may be applied up to 21 days before harvest.
Matrix herbicide is active against several annual grasses and broadleaves, including mustards and pigweeds. It has fair activity against most of the composites, but is weak on common groundsel. It is also weak on common lambsquarters and eastern black nightshade. It will provide six to eight weeks of weed suppression at the labeled rate, and is most effective if used with other residual herbicides. Matrix will also provide suppression of yellow nutsedge. To obtain the most effective results, use the highest rate allowed based on the width of your spray band and make two applications. Make the first application when emerging nutsedge is 2 to 4 inches tall and repeat application 14 days later. If yellow nutsedge is greater than 6 inches tall at the first application, weed control effectiveness will be greatly reduced
Matrix is a group 2(B) ALS inhibitor; Sandea is the only other group 2 herbicide labeled and widely used in fruit crops. Matrix is a good tank-mix partner with the PS II inhibitors such as Karmex, Group 7(C2), or Princep, Group 5(C1), and the PPO inhibitors such as Chateau or Zeus, Group 14. However, growers should be reminded that population of common ragweed and marestail/horseweed in New Jersey have evolved resistance to ALS inhibiting herbicides. Therefore, we recommend that a foliar active herbicide with activity on common ragweed and marestail/horseweed (such as paraquat or glufosinate) must be tank mixed with Matrix SG herbicide for best control and resistance management when these weeds have already emerged.
Other commercial rimsulfuron herbicides may include these crops on the label. For instance, Solida from FMC includes blueberry and caneberry on the label
The new Supplemental Label is available from the internet at CDMS