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Pigeon Tremex Horntail

Frequently mistaken for a giant wasp, pigeon tremex horntails are actually a non-stinging insect that begins life as a wood borer of several species of trees including silver maple, ash and elm.  They have also been known to attack conifer trees in forested areas.  Pigeon tremex horntails are not commonly considered as a pest that requires control methods simply due to the fact that they attack only seriously diseased or recently dead branches.  Females are significantly larger than males and equipped with a spear-like projection resembling a giant stinger on the rear of their abdomen.  This spine is actually the ovipositor that the female plunges into the wood of the tree in order to deposit her eggs below the surface.  In addition to the eggs, Daedalea unicolor is also introduced into the wood of the tree and is a form of white rot fungus.  The fungus works its way through the branch ahead of the pigeon tremex horntail larvae softening the wood for consumption by the larvae.  Females laying eggs are often seen crawling over the surface of the tree bark depositing eggs and at times are found deceased with their ovipositor stuck into the bark.  The most common natural enemy of pigeon tremex horntails is the giant ichneumon wasp.