Revisiting the insecticide: Actara
By: Christelle Guédot, UW-Madison, Department of Entomology
Actara is registered for use in Wisconsin on several fruit crops including pome fruit, stone fruit, berries and small fruit, and cranberry. It is marketed by Syngenta© under the formulation 25WDG (25% of active ingredient as Water-Dispersible Granules). Actara is in the class of the neonicotinoids (IRAC group 4A), with a mode of action targeting the nicotinic acetylcholine receptors in the nervous system, causing uncontrolled overstimulation. Actara contains the active ingredient thiamethoxam and acts as a systemic insecticide when applied as a seed treatment and as a trans-stemic insecticide when applied foliarly. When applied directly to foliage, the trans-stemic movement from the leaf surfaces into the leaves forms a reservoir of active ingredient within the leaves that provides long residual activity. Actara is fast acting on contact or by ingestion of treated plant surfaces. Affected insects will rapidly stop feeding, become paralyzed, and eventually die. Actara will kill both chewing and sucking insects and has broad spectrum activity on many insect species. Actara, Assail, Venom, Admire Pro, Alias, and Widow have the same mode of action and should NOT be used together in rotation, but rather insecticides from other IRAC groups (other than IRAC group 4) should be used in rotation with Actara to delay insecticide resistance.
Under cranberry, Actara is registered to control aphids, cranberry flea beetle, cranberry weevils, leafhoppers, and Japanese beetle. We have included this product in Jack Perry’s trials for several years and have found it to provide excellent control of flea beetle adults post bloom. Trials are ongoing this year to test its efficacy on blunt-nosed leafhopper.
Actara may be applied by ground equipment and should be used with at least 10 GPA for ground applications. Some restrictions apply for chemigation and sprinkler irrigation and Actara cannot be applied by air in cranberry. For more information on mixing, spraying, and all other considerations, please see the product label.
Actara is highly toxic to bees exposed to direct treatment on blooming plants and cannot be applied when bees are foraging and until flowering is complete. It is also not recommended to spray this product before bloom as the active ingredient can be found during bloom in the flower nectar and pollen. Actara is toxic to wildlife and highly toxic to aquatic invertebrates and must not be applied directly to water or to areas where surface water is present. A surface-water advisory warns that this product may affect surface water quality from spray drift and runoff. Specifically under cranberry, the label states to not apply within 25 feet of bodies of water. Please check the label for more information on these warnings.
Please check with your handlers before using any product as PHIs may vary from the one stated in the label*. Some handlers are applying a 45 day PHI on Actara in 2021. As always, make sure to read the label before using any pesticide. You can find the label of Actara at the following link: https://www.syngenta-us.com/current-label/actara
Happy growing season!