Willow-pest
Guides
Aculops tetanothrix
willow gall mite
Aculops tetanothrix, commonly known as the willow gall mite, is an eriophyid mite species that induces gall formation on Salix (willow) species. The mite has been documented in parts of Europe including Belgium and Denmark. It is characterized by yellow body coloration with brown or sometimes orange markings. The galls it produces on willow foliage initially appear green and later develop red coloration.
Bactericera minuta
Bactericera minuta is a small psyllid species native to North America that has become adventive in South America, where it was first recorded in Colombia. It feeds on willow species (Salix), particularly Salix humboldtiana, and has been associated with phytoplasma disease symptoms in infested trees. The species was originally described in 1910 and represents one of only two Bactericera species known from South America, where the genus is not native.
Phratora
Phratora is a genus of leaf beetles (Chrysomelidae) distributed across the Northern Hemisphere in cool, moist regions where their host plants occur. The genus is synonymous with Phyllodecta. Species in this genus feed primarily on willows (Salix), poplars (Populus), or birch (Betula), with host plant associations showing evolutionary conservation—closely related beetle species tend to feed on closely related plant species. European species are difficult to distinguish by external morphology alone and require examination of female genitalia for reliable identification. Several species, particularly Phratora vulgatissima, are economically significant pests of short-rotation coppice willow plantations.
Plagiodera
willow leaf beetles
Plagiodera is a genus of leaf beetles in the subfamily Chrysomelinae, containing approximately six recognized species distributed across the Holarctic region. The genus is best known for Plagiodera versicolora, commonly called the imported willow leaf beetle, which has been introduced to North America from Europe and is a significant pest of willow and poplar species. Members of this genus are specialized herbivores of Salicaceae, with well-documented chemical ecology and host-plant interactions.
Plagiodera versicolora
Willow Leaf Beetle, Imported Willow Leaf Beetle
Plagiodera versicolora is a small leaf beetle in the subfamily Chrysomelinae, commonly known as the willow leaf beetle or imported willow leaf beetle. Native to Europe and the Mediterranean region, it has been introduced to North America and occurs in parts of Asia. The species is a specialist herbivore on Salicaceae, feeding on willow and poplar leaves throughout its life cycle. Adults overwinter in protected locations and become active in spring, with multiple generations developing through summer. The species has been extensively studied for its chemosensory biology, host plant interactions, and as a model for understanding insect-plant coevolution.
Tuberolachnus
giant willow aphid, giant bark aphid
Tuberolachnus is a genus of aphids in the family Aphididae, established by Mordvilko in 1909. The genus contains three described species, with Tuberolachnus salignus (the giant willow aphid) being the most well-known and widely studied. Members of this genus are among the largest aphids in the world, with body lengths reaching up to 5.8 mm. They are notable for their obligate parthenogenetic reproduction, extremely low genetic diversity, and status as invasive pests in multiple regions including New Zealand, India, and Patagonia.
Tuberolachnus salignus
Giant Willow Aphid
Tuberolachnus salignus, the giant willow aphid, is one of the largest aphid species in the world, reaching up to 5.8 mm in body length. It is an obligate parthenogenetic species, reproducing without males and producing genetically identical female offspring. Native to Asia, it has become cosmopolitan, spreading to all continents except Antarctica. The species feeds primarily on willow phloem sap and is considered an invasive pest in regions including New Zealand, where it impacts willow-based industries and apiculture through copious honeydew production.