Yes, A. officinalis is introduced. It is a traditional edible herb, quite tasty with a mild garlic flavor, I've tried it. It has escaped from cultivation, and spreads in moist shady conditions, such as riparian woodlands. Its chemical constituents, which can be smelled and tasted by the adult butterflies, attract them to oviposit, but something about the chemicals eventually kills the larva, whether it is a toxin or a deficiency, I don't know. Other species of butterflies in the White group may be susceptible too, as many of them depend on Mustard family hostplants which contain similar chemicals. I don't know how much of this is theory, and how much has been actually confirmed in the field. I suspect there is some truth to it, but perhaps not as bad as it might seem. Supposedly, the use of Mustard family plants was an adaptation for protection from predation by becoming immune to toxins common in the hostplants that remain toxic to certain predators, much like Monarchs and milkweeds. Perhaps the garlic mustard situation is an example of this in progress.
Don Holt -----Original Message----- From: Michael <mlbierly@xxxxxxxxxxxxx> To: Tennessee Butterflies <tn-butterflies@xxxxxxxxxxxxx> Sent: Fri, 6 Feb 2009 10:38 pmSubject: [TN-Butterflies] Re: Pieris virginiensis - a couple more questions
Thanks Don for the information on why Garlic Mustard, Alliaria officinalis, is one cause for the de cline of Pieris virginiensis. Is this plant introduced? And, is it known why the eggs do not succeed on this plant? Perhaps toxic to the young caterpillars? Much thanks.
Michael Lee Bierly, Nashville, Davidson County, TN Please report any abuse or questions about this list to: tanya_jordan@xxxxxxxxxxxx Users can unsubscribe from this list by sending email to tn-butterflies-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field.
