About Palm Weevils in Texas
Palm weevils are among the most destructive pests affecting palm trees in Texas. These large beetles bore into palm trunks and crowns, where their larvae feed on internal tissues, causing severe damage and often killing the tree.
The most concerning species in Texas is the Giant Palm Weevil, though the invasive South American Palm Weevil is also a growing threat. Once established, palm weevils are extremely difficult to control because they spend most of their life cycle hidden deep inside the palm.
Palm weevil infestations often go unnoticed until significant damage has occurred. By the time external symptoms appear, the tree may be beyond saving. Early detection and preventative treatment are critical for protecting valuable landscape palms.
Common Palm Weevil Species in Texas
1. Giant Palm Weevil (Diocalandra frumenti)
Native to Texas. Dark brown to black, 1/2 inch long. Long curved snout (rostrum). Infests stressed or wounded palms. Larvae bore through trunk and fronds. Multiple generations per year.
2. South American Palm Weevil (Rhynchophorus palmarum)
Invasive species, spreading in Texas. Reddish-brown to black, 1-2 inches long. One of the largest weevils. Extremely destructive. Carries red ring nematode which is fatal to palms. Subject to quarantine regulations.
3. Mexican Palm Weevil (Rhynchophorus palmarum mexicanus)
Related to South American species. Black with reddish tinge, 3/4-1 inch. Attacks Canary Island date palms, California fan palms. Larvae tunnel through crown and trunk.
Identification Guide
Size
Giant: 1/2 inch | South American: 1-2 inches | Mexican: 3/4-1 inch
Color
Dark brown to black, some with reddish tinge
Features
Long curved snout (rostrum), hard shell, cylindrical body
Life Cycle
- Adults attracted to stressed, wounded, or freshly trimmed palms
- Females bore into palm tissue and lay eggs
- Larvae hatch and tunnel through interior for 2-4 months
- Pupate inside palm, then emerge as adults
- Multiple overlapping generations throughout year in Texas
- Complete life cycle: 2-4 months depending on temperature
Signs of Palm Weevil Infestation
Early Warning Signs:
- Oozing or fermenting sap from trunk or crown
- Wet spots or dark staining on trunk
- Sawdust-like frass (insect waste) at base of palm
- Wilting or off-color fronds when tree should be healthy
- Holes bored into trunk or leaf bases
Advanced Infestation Signs:
- Multiple fronds yellowing, wilting, or collapsing
- Crown leaning to one side or collapsing
- Hollow sound when trunk is tapped
- Tunnels visible in cut frond bases
- White, legless larvae (grubs) visible in trunk if cut open
- Strong fermentation odor from damaged tissue
- Adult weevils visible on trunk (usually at dusk or night)
High-Risk Conditions:
- Recent pruning or trimming injuries
- Storm damage or broken fronds
- Nearby infested palms
- Stressed palms (drought, poor nutrition, disease)
- Fresh transplants
Palm Tree Damage & Risks
Direct Tree Damage
- Larvae tunnel through trunk destroying vascular tissue
- Damage to crown kills growing point (apical meristem)
- Loss of crown growing point is fatal—palms cannot regenerate
- Weakened trunk becomes structurally unstable
- Severely infested palms often collapse
- Death can occur within months of initial infestation
Disease Transmission
- South American Palm Weevil carries red ring nematode
- Red ring disease is fatal to palms—no cure
- Weevils spread disease between palms during feeding
- Secondary fungal and bacterial infections in damaged tissue
Economic & Aesthetic Losses
- Mature landscape palms cost $500-$5,000+ to replace
- Removal and disposal of large dead palms expensive
- Loss of property value and curb appeal
- Risk of falling palm causing property damage or injury
- Quarantine restrictions if regulated species detected
Spread to Other Palms
- Adult weevils fly to nearby palms
- Attracted to fresh pruning cuts and wounds
- Can decimate entire palm collections
- Neighborhood-wide infestations possible
Prevention Strategies
Pruning Practices
- Only prune palms during cool months (November-February) when weevils less active
- Never prune during warm months unless absolutely necessary
- Make clean cuts—ragged cuts attract weevils
- Remove only dead or damaged fronds—excessive pruning stresses palms
- Apply protective insecticide to fresh cuts immediately
- Seal large wounds with wound dressing
Palm Health Maintenance
- Healthy palms better resist weevil attack
- Provide adequate water, especially during drought
- Fertilize appropriately with palm-specific fertilizer
- Treat nutrient deficiencies (especially manganese)
- Avoid trunk or root injuries during landscaping
Monitoring & Early Detection
- Inspect palms monthly for early warning signs
- Check base of palms for frass or oozing sap
- Monitor palms after pruning or storm damage
- Be alert to infestations in neighborhood palms
- Use pheromone traps to monitor adult weevil populations
Sanitation
- Remove and destroy infested palms promptly
- Chip or burn infested material—do not compost
- Remove pruned fronds from property immediately
- Don't leave palm debris near healthy palms
- Follow quarantine regulations if applicable
Professional Palm Weevil Treatment
Palm weevil control is difficult because larvae are protected deep inside the palm. Treatment requires specialized knowledge, proper timing, and professional-grade products.
Our Treatment Protocol
Comprehensive Palm Inspection
Visual assessment of all palms. Check for early warning signs. Identify high-risk conditions. Document palm health and any damage
Preventative Insecticide Applications
Trunk injections or drenches of systemic insecticides. Product moves through vascular system killing larvae. Repeat treatments as needed (typically 3-4 month intervals)
Spray Treatments for Wound Protection
Apply insecticide to fresh pruning cuts and wounds. Prevents adult weevils from laying eggs. Critical after any pruning or damage
Pheromone Trapping
Place pheromone-baited traps to monitor and capture adult weevils. Helps detect infestations early. Reduces local adult populations
Infested Palm Management
Assess whether treatment is viable or removal necessary. Severely infested palms should be removed promptly to prevent spread. Proper disposal of infested material
Ongoing Monitoring
Regular inspections to catch problems early. Adjust treatment schedule based on weevil activity and palm condition
Treatment Cost Expectations
Costs vary based on palm size, number of palms, treatment method, and accessibility
Common Questions
Q: Can an infested palm be saved?
It depends on severity. Early infestations may respond to aggressive treatment with systemic insecticides. Once the crown is damaged or extensive tunneling has occurred, the palm cannot recover and should be removed to prevent spread.
Q: Which palm species are most susceptible?
Canary Island date palms are highly susceptible. California fan palms, Mexican fan palms, and true date palms are also frequently attacked. Some palm species (like sabal palms) are more resistant but not immune.
Q: How do I know if treatment is working?
No new damage appearing (no fresh frass, oozing, or wilting fronds). Crown remains green and firm. Tree continues producing new fronds normally. Complete evaluation may take 3-6 months as existing larvae die.
Q: Should I preventatively treat healthy palms?
Yes, if you have high-value landscape palms, live in areas with known weevil activity, or have had infestations before. Preventative treatment is far more effective and less expensive than trying to save an infested palm.
Q: Can I treat palm weevils myself?
DIY treatment is difficult. Effective systemic insecticides require special equipment for trunk injection. Proper diagnosis is critical—symptoms can resemble other palm problems. Professional treatment provides better results and protects your investment.
Protect Your Palms from Weevils
Don't wait until it's too late.
Let us protect your valuable landscape palms.