Palm Weevil Disease and Treatment Admin September 20, 2019

Palm Weevil Disease and Treatment

Palm Tree and Arborist Services San Diego Area

ISA Certified Arborists Offer Tips for Saving Your Palm Trees


Did you know the palm trees on your San Diego property currently face the threat of Palm Weevil disease? A few years ago, hordes of highly damaging invasive pests, called the South American Palm Weevils (SAPW) made their way from Mexico to the San Diego region. Today, they are creating more havoc and destruction than ever before, particularly to the palm trees in the San Diego area. The ISA-certified arborists at Rancho Coastal share some useful insights about Palm Weevil disease and its treatment.

Tips to Tackle the SAPW Threat to Your Beautiful Swaying Palms


While the weevils originally migrated north around 2011, their numbers have multiplied and infestations have spread rapidly in the last couple of years. In fact, the SAPW is now California’s biggest weevil species, affecting at least 35 different plants. These destructive pests primarily attack Canary Island Date Palms. Since date palms are at the center of a multi-million dollar date growing industry, SAPW poses a huge economic and ecological threat to the San Diego County.

Here are some things you should know about Palm Weevil disease and its treatment, in order to protect your precious palms:

  • What is the SAPW? The adult weevils are about 1.5 inches long, black in color, have a long rostrum (snout) and are strong fliers. At the larva stage, weevils are whitish in color and can grow up to 5 inches long, when they pupate inside their fibrous cocoons. You will usually sight the cocoons in the crown region of the palm tree, or at the base of the palm’s fronds.
  • How do SAPWs infect your palm trees? Weevils use their long rostrum to drill holes at the base of the palm fronds, or in the crown region of the tree. The female then lays eggs in the tunnels, and the larvae that hatch from the eggs burrow into the palm crown for their feed. Essentially, they attack the meristematic tissues, or the ‘palm heart’ that produces new fronds and they turn the tree tissues into a fermented mash. When left undetected, this damage is irreversible and will leave you with no choice but to remove your palm trees.
  • How can you diagnose a weevil infestation? The problem is, you can’t! Early stage infestation is very hard to notice, and symptoms become visible or apparent only after it progresses. Some of the noticeable indications of weevil presence are:
    1. Damaged fronds emerging from the center of the crown
    2. Leaflets that appear notched, clipped or windowed
    3. Crown starting to collapse
  • What is the best way to tackle the SAPW? Infected palms become weak at their core. The risk of collapse or palm fronds dropping pose a significant safety hazard to people, vehicles, pets and property. Moreover, heavy winds and rain could further aggravate and accelerate the fall. Applying systemic insecticides to the crown, trunk or soil, before there is permanent damage to the crown, can help cure moderate to heavy weevil infestation. Once you begin applying these pesticides, you need to continue their usage indefinitely to protect your trees from future weevil attacks.

Timely Tree Care and Tree Pest Control Can Help Your Palms Thrive


Removing dead palms is both difficult and time consuming. Your best bet is to conduct routine tree care for early detection of tree pests and timely treatment of tree diseases. At Rancho Coastal, our ISA-certified arborists can identify and control tree pests and diseases, before they damage your trees irreversibly. We use environment-friendly, long-lasting measures to save your swaying palms, and nourish them back to health. We also offer safe, affordable and hassle-free tree removal services, when required.

Certified by the Tree Care Industry Association (TCIA), Rancho Coastal is a licensed, bonded and fully insured tree service company. Customers across the San Diego area, including Coronado, Del Mar, La Jolla, Pacific Beach and Rancho Santa Fe, CA count on us for our specialized tree care services.

Safeguard your ornamental, native and date palm trees from weevils and other pests. Talk to the Certified Arborists at Rancho Coastal about plant health care. Call us at 619-847-4225 to inquire about our range of tree services or contact us online.

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