Pinus-pest

Guides

• Eulachnus rileyi

  pine needle aphid

  Eulachnus rileyi is a pine needle aphid native to North America that has become established in pine plantations across Africa, South America, and Europe. It feeds on phloem sap of pine needles, showing preference for 3-4 year old foliage. Populations exhibit bimodal peaks in spring and autumn, with crashes during heavy rainfall periods. The species reproduces parthenogenetically, producing both winged dispersal forms and wingless forms. It is considered a significant pest in commercial pine plantations, where dense infestations can cause needle yellowing, reduced growth, and tree stress.

  pine-needle-aphidplantation-pestinvasive-speciesparthenogenesisbiological-controlaphididaepinus-pesttemperate-pestforestry-pestHemiptera

• Pachylobius picivorus

  pitch-eating weevil, pitch eating weevil

  Pachylobius picivorus, commonly known as the pitch-eating weevil, is a pine root-feeding weevil native to North America. The species is an economically significant pest of natural and planted pine seedlings, with brood development requiring 100–128 days during summer. Adults are long-lived and oviposit continuously at approximately 0.7 eggs per day per female throughout their lifespan. Populations exhibit two annual peaks in the Georgia Piedmont, driven by temperature and developmental cycles. Behavioral studies indicate the species responds strongly to olfactory cues, particularly ethanol and turpentine mixtures, though visual cues are less important for host location than in related species such as Hylobius pales.

  pine-weevilroot-feeding-weevilforestry-pestPinus-pestCurculionidaeNorth-AmericaGeorgia-Piedmonttrap-response-behaviorethanol-turpentine-responsepine-seedling-damagelong-lived-adultcontinuous-ovipositionpopulation-peakssummer-brood-developmentolfactory-cue-responsevisual-cue-secondaryTedders-trapmodified-Tilles-trapeconomic-pestforest-regeneration-pestlarval-root-feedingpine-plantation-pestbehavioral-ecologyhost-finding-behaviorground-dwelling-weevilPachylobiusMolytinaePissodini