Pre-emergence herbicides for use in Christmas tree plantations
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
Editor’s note: This article was first published in the April 13, 2007 Landscape Alert and has slight revisions by Jill O’Donnell to reflect this year’s activity.
Pre-emergence herbicides are useful in Christmas tree production to prevent competition from undesirable weeds. A couple of newer herbicides have recently been added to the list available for producers: Westar and SureGuard (flumioxazin). Westar (hexazinone plus sulfometuron) is a premixture of Velpar (hexazinone) and Oust (sulfometuron). Westar rates range from 6 to 12 oz/A. Use the lower rates on coarse textured soil and where conifer tolerance is a concern. SureGuard also provides good to excellent control of most weed species. Rates for SureGuard are from 8 to 12 oz/A. Add 1 pt/A to 1 qt/A of Roundup Original to the SureGuard tank as emerged weeds are present at spraying.
Previous research has shown both herbicides provide nearly season long control. Other products include Princep (simazine) at 2 qts/A plus Aatrex (atrazine) at 1 qt/A. Use only in fields where incidence of triazine resistance is not an issue. Kerb 50W (pronamide) at 3 to 4 lb/A plus Princep at 2 qts/A is also a good option.
Finally, Princep at 2 to 4 qts/A plus Surflan AS (oryzalin) at 3 to 4 qts/A or Pendulum EC (pendimethalin) at 2.4 to 4.8 qts/A or Pennant Magnum (s-metolachlor) at 1 1/3 qts/A or Barricade (prodiamine) at 2.3 lbs/A. The most important thing to remember is to apply these herbicides before budbreak. As with any herbicide product, please consult the label for specific rates and instructions regarding its use in your plantation.