CRB adults visit trees for feeding but do not typically stay in trees very long. A CRB may feed on different trees throughout their life. Treatments to trees include pesticides and physical barriers. Physical treatments can protect a single palm but pesticides should be applied to all palms in an area to be effective. While these treatments are great tools, no one treatment is a 100% guarantee against CRB. For trees to have the best chance at recovery, community-wide treatment and green waste management are important, to have a significant impact on the beetle population in your area.
Pesticides are applied as foliar sprays, systemic injections, or systemic root drench. Since systemic pesticides require CRB to feed on the palm to die, damage will still occur but will be reduced when there is a reduction in the local CRB population. Always refer to the labels when applying pesticides.
Imidacloprid (e.g. ImaJet) and Acephate (e.g. AceJet) kill CRB in lab trials and have reduced populations when applied to most palms in an area. Systemic injections require trimming of flowers and fruits at least every 6 months to protect pollinators and ensure the fruits are not consumed.
Imidacloprid (e.g. Imidacloprid 75 WSP) can be applied as a soil drench for systemic treatment of palms. Field efficacy has not been tested for this application method. Soil drench with imidacloprid requires trimming of flowers and fruits at least every 6 months to protect pollinators and ensure the fruits are not consumed. Fully trimmed palms can be treated as “shrubs” when consulting the label for application instructions. Full instruction for soil drench click here.
Spraying of the crown with cypermethrin has been shown to kill CRB in the lab and field. Some of these pesticides can only be applied by certified pesticide applicators. Spraying the spear and upper central part of the crown will be more effective than spraying outer and lower frond areas.
“Evergreen Pyrethrum Concentrate” is a USDA Organic certified product that can be used on all CRB hosts and infested material. Pyrethrin is purified from plants and kill CRB by contact causing paralysis. Spray of the crown center can kill adult beetles inside the palm. Pyrethrin degrade quickly in sunlight,
so this product does not provide long-term residual activity. This should only be applied to plants with recent CRB damage or suspected to have CRB actively feeding. For full instruction for Evergreen application, click here.
Netting can entangle and exclude CRB from accessing the crown of the tree. Netting should be one inch stretched hole size to three inch stretched hole size and wrapped around the base of the spear in 2 or more layers and stuffed between the bases of fronds near the spear. For more information about applying netting click here. Please note that the netting recommended for this treatment is illegal to use for fishing in Hawaii and should only be used for palm treatment.
Sand can be applied to the crown so that it sits between the bases of the fronds surrounding the spear. The efficacy of this treatment has not been tested. Sand requires regular reapplication as it washes away and new fronds grow out from the spear.
Businesses that offer treatments coming soon!
If you are a business that offers treatment for CRB please reach out to us. If your treatments aligns with our recommendations we will add you to our list.