The Pineapple gall adelgid (Adelges abietis) is a type of conifer-feeding insect that forms pineapple-shaped plant galls on its host species, commonly Norway and Sitka spruce. The adelgids (genus Adelges) are pear-shaped, soft-bodied green insects with long antennae, closely related to the aphid. Adelges lays up to one hundred eggs at a time, one on each needle. Adelges abietis (Linnaeus, 1758) is one of the most common species; synonyms are A. gallarum-abietis, Chermes abietis and Sacciphantes abietis.
The pineapple gall adelgid is endemic to Europe, belonging to the 'woolly adelgid' group; it is also widely distributed in the north-eastern United States. Spruce gall aphid, eastern spruce pineapple gall adelges and eastern spruce gall aphid are alternative names. This insect belongs to the superfamily Aphidoidea, and family Adelgidae. It is the primary pest of Norway Spruce. Another similar species, the Cooley spruce gall adelgid, is indigenous to North America. This adelgid usually affects Colorado Blue, Sitka, Englemann, and Oriental spruces.
The eastern spruce gall adelgid (Adelges abietis Linnaeus) is an introduced species that feeds only on spruce. At least in 1985, the species was found in Canada from Ontario eastward and in adjacent parts of the United States.
There are no known effective parasites or predators of Adelges abietis. Specimen trees in gardens may be afforded a degree of protection by hanging up fat balls to encourage tits which will also feed on the adelgid gall formers.
Search this siteAdelgidae : Adelgini : Adelges abietis Adelges abietisEastern spruce gall adelgid, Pineapple gall adelgidOn this page: Identification & DistributionBiology & EcologyOther aphids on the same hostDamage & ControlIdentification & Distribution:The Adelges abietis gall on spruce, known as a 'pineapple gall', (see first picture below) is ellipsoidal with its length less than 1.5 times the width and usually about 15-20 mm in length. The spruce needles on the gall are shorter than normal and are a slightly paler green than on a normal shoot. The slits to gall chambers are often orange-red or deep pink before opening. There are often several galls together at the base of adjacent shoots, and plant growth often continues beyond gall. The gall is initiated by the pseudo-fundatrix (not pictured) which is yellowish-green to light green with 5-segmented antennae. The offspring of the pseudo-fundatrix which live inside the gall (see second picture below) are a yellowish orange and are densely waxed. The gall chambers open in August-September to release the gallicolae.
Most spruce trees are damaged by one of two species of adelgids: the Eastern spruce gall adelgid (Adelges abietis) and the Cooley spruce gall adelgid (Adelges cooleyi). With their sucking mouth-parts, these adelgids feed on plant juices, causing an irritation that results in plant tissue developing into cone-like galls characteristic in form and shape for the aphid species involved. Continued infestations disfigures ornamental and Christmas trees, weakening them, and making them subject to attack by other pest organisms.
Adelges abietis är en insektsart som först beskrevs av Carl von Linné 1758. I den svenska databasen Dyntaxa används istället namnet Sacchiphantes abietis. Enligt Catalogue of Life ingår Adelges abietis i släktet Adelges och familjen barrlöss, men enligt Dyntaxa är tillhörigheten istället släktet Sacchiphantes och familjen barrlöss. Arten är reproducerande i Sverige. Inga underarter finns listade i Catalogue of Life.
Two species of small, soft-bodied insects infest spruce species during the course of rather complicated life cycles. These aphid-like insects called adelgids, produce galls that can disfigure and even kill their hosts. The two adelgids that can be found in the Chicago region are the eastern spruce gall adelgid (Adelges abietis) and the Cooley spruce gall adelgid (Adelges cooleyi). 59ce067264