Ask the Expert: Stay Ahead of Tree Nut Weeds Year-Round

Matrix® SG herbicide provides year-round tree nut weed control.


How can I control tough winter broadleaf weeds and extend grass control in my tree nut orchards longer into summer?


Implementing a proactive residual weed-control program that stops weeds before they emerge is key to staying ahead of weeds throughout the year.

No matter what the weather brings us, application flexibility is a huge advantage with DuPont™ Matrix® SG herbicide. In field studies, sequential applications in the fall and spring that include Matrix® SG as the foundational residual herbicide can help achieve excellent preemergence weed control in fall and winter and extend residual weed control into late spring and summer. Applying Matrix® SG in sequential treatment programs  ̶̶  one 50 percent or less banded treatment in the fall and a second 50 percent or less banded treatment in the spring  ̶̶  will reduce the need to use multiple applications of burndown herbicides during busy summer months.

To manage a broad spectrum of weeds, apply Matrix® SG at 4.0 ounces per acre (50 percent or less banded treatment)1 with other herbicides registered for use in tree nuts.  Choices of tank-mix partners with Matrix® SG as a sequential application in the fall (November through December) should be based on targeting the orchard’s most important weed problems during the fall/winter months (e.g. fleabane, marestail, malva, filaree, panicle willowweed, annual bluegrass and Italian ryegrass).

Because fleabane and marestail can emerge for eight to 12 months in some areas of the Central Valley, a follow-up sequential application of Matrix® SG in the spring (mid to late February through March) is advisable to extend residual control of these key broadleaf weeds. Matrix® SG should include an appropriate tank-mix partner that is labeled for safe and effective non-dormant use and can extend preemergence weed control of important summer grasses, including barnyardgrass and crabgrass. Matrix® SG tank mixtures with DNA herbicides (e.g. Prowl and Surflan) or Alion have provided the most effective and extended summer grass control when applied in the spring.

Matrix® SG offers flexible control options, providing both preemergence2 and early postemergence3 control of difficult-to-control broadleaf weeds and grasses, plus suppression of yellow nutsedge. Effective at a low use rate, Matrix® SG has no soil restrictions and may be applied during dormant and non-dormant periods in broadcast, band or micro-sprinkler applications4.

1Always read and follow all label directions and precautions for use for Matrix® SG and all tank-mix herbicide partners.

2 See Matrix® SG specimen label and 2ee recommendations for weeds controlled by preemergence applications.

3 See Matrix® SG specimen label for weeds controlled early postemergence.

4 See Matrix® SG specimen label for product use limitations based on application method.


The information provided on this website is for reference only. Always refer to the product labels for complete details and directions for use.