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Pest Status
Background
Chapter 29
Artemisia absinthium L., Absinth
(Compositae)
M.G. MAW and D. SCHROEDER
Artemisia absinthium L. is indigenous to temperate Europe and Asia and was introduced to
North America as a medicinal and flavoring herb some time before 1832. By 1841.
absinth had escaped from gardens and was recognized as an established weed in the
United States (Mitich 1975). The weed was first recorded in Canada at Fort Garry.
Manitoba in 1860 (Scoggan 1957). By 1883, absinth was considered to be naturalized in
numerous locations from Newfoundland to western Ontario (Mitich 1975). Although it is
abundant in the Prairie Provinces. it was not recognized as a serious weed until 1954
(Frankton & Mulligan 1970).
Absinth can now be found in all provinces of Canada and in many of the northern
states but with few exceptions it is confined to farm yards, around grain elevators, and
along the edges of fields, railways, and roadsides. It is controlled by cultivation but can
be spread into pastures, hayfields, and crop lands. Rapid increase in the spread of the
weed on the prairies is associated with relatively moist conditions (Selleck & Coupland
1961).
Although absinth may flavor milk, and grain from infested fields may be rejected
because the flour might be tainted (Selleck & Coupland 1961), such occurrences are
rare. Cattle will not graze on absinth by choice, but may inadvertently consume it in hay.
Absinth is a health hazard as the odor can cause illness in those working in infested
fields. and its pollen causes great discomfort in those sensitized by it.
While absinth is controlled by cultivation, the farming techniques of minimal or zero
tillage might permit the weed to become a serious problem in some areas.
At Canada's request. surveys of absinth insects in Europe were undertaken by the
Commonwealth Institute of Biological Control. A literature review suggested that
Euzophera citlerosella (Zeller) (Lepidoptem: Pyralidae), a stem and root miner, was
specific to A. absimhillm (Miotk 1973). Field surveys in Austria, Germany, France, and
the Swiss Valais showed that E. cinerosel/a occurs in most populations of absinth
throughout its European mnge, and that it causes serious damage to its host (Schroeder
1979).
E. cillerosella emerges about the end of May to the end of July and mating takes place
within 24 hours of the female's emergence. Males mate several times; females just once.
Oviposition starts the day following mating with 12 eggs laid daily for the first four days.
Over 100 eggs may be laid during June and half that number during July.
The eggs arc deposited on the lower leaves and hatching occurs in 8-10 days. The
young larvae commence to feed on the upper cuticle of the leaf but soon bore into the
leaf petiole destroying the bud in the leaf axil, then downwards, feeding on the vascular
tissue of the shoots. As the season advances, the larvae reach the roots and destroy
the outer parts before mining into the woody tissue. The winter is passed as hibernating
larvae and puplltion takes pl.lce in the spring within a silken cocoon in a pupal cell near
the root crown.
Damllge to the host plant depends on the development of the larvae. First and second
instars clluse little damage. but third and fourth instars mine the cambium and vascular
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