New Tools in the Herbicide Arsenal

     Treevix 70%WG was labeled early last year and is sold by BASF as a post-emergence directed broadleaf herbicide for pome fruit that have been established at least 12 months. It has no activity against grass weeds. The active ingredient is salfufenacil and has a similar mode of action as Chateau. While it is primarily a burn-down material it has a little residual action. Application rate is 1 oz per acre plus a crop oil concentrate plus ammonium sulfate. It can be applied up to 3 times per season separated by at least 21 days between applications. Do not exceed 3 oz/A per year. There is a 0 day pre-harvest interval and 12 hour re-entry interval. Treevix must be applied to actively growing weeds that are not stressed due to drought; the timing depends on the weed species and the height of the weed. In my trials last year it worked very well on burning down marestail but will also work on pigweeds, ragweed, lambsquarters, and morning glory species and other broadleaf weeds. Do not allow contact with any green tissue on apple or pear trees.

     Sandea 75% DF is a new herbicide from Gowan. The active ingredient is halosulfuron-methyl and it is also primarily a post-emergent material with some pre-emergent activity for broadleaf weeds and nutsedge. It is labeled for apples and highbush blueberries as a supplemental label for both. You will need a copy of the supplemental label as well as the original in your possession. I think the greatest use for this material will be on controlling nutsedge. For nutsedge control apply Sandea post-emergent as a single spray at a minimum of 0.75 oz/A when nutsedge plants are in the 3-5 leaf stage. If needed, a second treatment may be applied later in the season to any secondary nutsedge emergence. Do not treat orchards where the trees are established less than one year. The pre-harvest interval is 14 days and the re-entry interval is 12 hours. For pre-emergent treatment, applications to bare ground work best. If small weeds are present, include a broad spectrum post-emergent material as well. Include a non-ionic surfactant in the mixture.

     Solida 25%WSG is a new product from Cheminova with the active ingredient of rimsulfuron; the same ingredient in Matrix FNV. Pruvin™ distributed by MANA is another rimsulfuron label. Rimsulfuron is labeled for stone fruit, tree nuts, pome fruit, and grapes. Certain grass and broadleaf weeds on selectively controlled. Trees and vines must be at least 1 year old when treated. There is a 7 day PHI for pome fruit, and 14 day PHI for stone fruit, tree nuts, and grapes. The re-entry limit is 4 hours. Best results are obtained when the soil is moist at the time of application. As a banded application (less than 50% of ground), apply Solida at 4 oz/A. A second banded application can be made a minimum of 30 days after the first for additional control. Avoid direct or indirect spray contact with foliage or fruit, except undesirable suckers. Some growers have seen good control of pigweed species when applying rimsulfuron.

     Chateau 51% WDG (flumioxazin) added a supplemental label last fall with additional restrictions and warnings. Some of these warnings include restrictions on soil types, danger of damage from dust from soils drifting onto trees, and proximity of non-dormant pears to the application site. As a reminder, Chateau should only be applied prior to “pink bud” in apple and “bud break” in stone fruit and pears. The preferred timing of application is in the fall to take advantage of the potential for rain to activate the material.