Beautiful but Deadly (Not really) H. Mantegazzianum produces a
sap that can cause photodermititis in the area of contact.
Furanocoumarins + Ultraviolet light from the Sun = photodermititis
Blisters can be long standing and prone to leaving scars.
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Furanocoumarins Chemical Defense System 8-Methoxypsoralen
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Invasiveness. Giant Hogweed is coming to an area near
you.!!!!
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Caucasus
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View Native Status
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Enemy Release Hypothesis Presicts that top down regulation of
the population will be lower in the range of introduction. When
introduced into a new area, H. Mantegazzianum has the ability to
outcompete native species. Obviously. Wolfe (2002)- found that
plants introduced into a new area were not susceptible to its
native herbivourous predators. The lack of such a selection
pressure would allow the plant to divert nrg and flourish in a non
native area iff, other conditions were suitable. i.e. temperature,
soil
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Evolution of Increased Competitive Ability A plant invests a
significant amount of energy into defense against herbivores in its
indigenous environment. A newly introduced species will not have
its usual host of herbivorous predators to weaken its fitness..
They lack Monophagous feeds within a plant genus (Heracleum)
Oligophagus restricted to one family ( Apiaciae) Polyphagous-
feeding on different families. ( Memmot et al 2000)
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Increased Interspecific Competition Interspecific competition
is when two different species depend on a common factor, and then
compete for it. The winner of such a factor is more fit for its
environment. Because H. mategazzianum has fewer natural enemies in
its unnatural environment it doesnt exert as much energy in
defending against attack. This energy is focused elsewhere..
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Diverts Saved Energy to Growth Energy Since the plant has the
ability to do so, it will use the supplemental energy in utilizing
growth processes. Improved growth processes will help the plant use
resources with a greater fitness, relative to other indigenous
species.
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Winter months contribute to competition H. Mantegazzianum dies
back in the winter, further eroding the soil and making it even
less unsuitable for other organisms to flourish.
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Sources Eur. J. Entomol. 103:387-395, 2006:ISSN1210- 5759