Pest identification
What's eating my wollemia pine?
Scale insects
Signs: Brown or white waxy lumps on bark and stems; yellowing foliage; sticky honeydew and sooty mould.
Control: Treat with horticultural oil or neem oil when crawler stage is active in spring. Remove isolated colonies manually with a soft brush dipped in rubbing alcohol.
Phytophthora root rot (Phytophthora cinnamomi / P. multivora)
Signs: Wilting fronds, browning needles, and dieback despite adequate watering. Root crown shows dark rot on inspection.
Control: Use well-drained, slightly acidic media. Avoid overwatering. Apply phosphonate-based fungicide preventatively in high-risk situations. Do not replant in infested soil.
Mealybugs
Signs: White cottony clusters at leaf axils and stem joints; stunted growth and sticky residue.
Control: Dab individual colonies with a cotton bud soaked in rubbing alcohol. Spray with neem oil or insecticidal soap; repeat every 10–14 days.
Looper caterpillars
Signs: Chewed or notched foliage on outdoor trees; visible caterpillars looping along branches in summer.
Control: Hand-pick small infestations. Apply Bacillus thuringiensis (Bt) spray for larger outbreaks; it is selective and will not harm beneficial insects.
Keep wollemia pine pest-free
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Wollemia Pine pests — FAQ
What is eating my wollemia pine?
Wollemi pine can be troubled by scale insects, mealybugs, and thrips, as well as looper caterpillars on outdoor specimens. The gravest threat is Phytophthora root rot — the species is known to be susceptible to Phytophthora cinnamomi and P. multivora, which is why biosecurity protocols exist around wild populations.
How do I get rid of scale insects on wollemia pine?
Brown or white waxy lumps on bark and stems; yellowing foliage; sticky honeydew and sooty mould. Treat with horticultural oil or neem oil when crawler stage is active in spring. Remove isolated colonies manually with a soft brush dipped in rubbing alcohol.
How do I get rid of phytophthora root rot (phytophthora cinnamomi / p. multivora) on wollemia pine?
Wilting fronds, browning needles, and dieback despite adequate watering. Root crown shows dark rot on inspection. Use well-drained, slightly acidic media. Avoid overwatering. Apply phosphonate-based fungicide preventatively in high-risk situations. Do not replant in infested soil.
How do I get rid of mealybugs on wollemia pine?
White cottony clusters at leaf axils and stem joints; stunted growth and sticky residue. Dab individual colonies with a cotton bud soaked in rubbing alcohol. Spray with neem oil or insecticidal soap; repeat every 10–14 days.
How do I get rid of looper caterpillars on wollemia pine?
Chewed or notched foliage on outdoor trees; visible caterpillars looping along branches in summer. Hand-pick small infestations. Apply Bacillus thuringiensis (Bt) spray for larger outbreaks; it is selective and will not harm beneficial insects.