Pest identification
What's eating my sonoran dioon?
Armored scale (Diaspididae)
Signs: Crusty brown or gray shells on caudex, stems, and leaflet undersides; slow decline and yellowing fronds
Control: Manual removal and horticultural oil applications; systemic imidacloprid soil drench for severe outbreaks
Mealybugs (Pseudococcus spp.)
Signs: White cottony masses at crown and leaf bases; honeydew promotes black sooty mold
Control: Alcohol swabs for spot treatment; neem oil or insecticidal soap spray; repeat every 10 days
Caterpillars (various Lepidoptera)
Signs: Ragged, chewed edges on new croziers and unfurling leaflets; frass present at base
Control: Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to protect newly emerging fronds
Keep sonoran dioon pest-free
Healthy plants resist pests best. Get the basics right:
Sonoran Dioon pests — FAQ
What is eating my sonoran dioon?
Sonoran Dioon is a heat-tolerant Mexican cycad grown as a landscape or patio specimen in warm climates. Scale insects are the dominant pest of cycads in this group. Outdoors, it can also attract mealybugs and occasional caterpillars that rasp on new croziers. Monitor the caudex closely year-round.
How do I get rid of armored scale (diaspididae) on sonoran dioon?
Crusty brown or gray shells on caudex, stems, and leaflet undersides; slow decline and yellowing fronds Manual removal and horticultural oil applications; systemic imidacloprid soil drench for severe outbreaks
How do I get rid of mealybugs (pseudococcus spp.) on sonoran dioon?
White cottony masses at crown and leaf bases; honeydew promotes black sooty mold Alcohol swabs for spot treatment; neem oil or insecticidal soap spray; repeat every 10 days
How do I get rid of caterpillars (various lepidoptera) on sonoran dioon?
Ragged, chewed edges on new croziers and unfurling leaflets; frass present at base Hand-pick caterpillars; apply Bacillus thuringiensis (Bt) spray to protect newly emerging fronds