As a matter of interest in the abstract below: "... A rapid assessment of the invasive status of Eucalyptus species at 82 sites in South Africa (54 in the Western Cape and 28 in Mpumalanga) indicated that only ....... flooded gum (E. grandis) are clearly invasive."
It may be worth considering that a species that is not invasive in wet Florida may well be invasive in the dry parts of the western US and vice versa. There are several instances to suggest that it is easy to underestimate the potential of a species to become a serious noxious weed. Juanita Ladyman Centennial CO Original: Title: A rapid assessment of the invasive status of Eucalyptus species in two South African provinces. Personal Authors: Forsyth, G. G., Richardson, D. M., Brown, P. J., Wilgen, B. W. van Author Affiliation: CSIR Division of Water, Environment and Forestry Technology, P.O. Box 320, Stellenbosch 7599, South Africa. Document Title: South African Journal of Science Abstract: Gum trees, or eucalypts (Eucalyptus species), have been targeted for invasive alien plant clearing programmes in many parts of South Africa. This has caused some dissatisfaction where the species concerned also have useful characteristics, and stakeholders contend that some of these useful species are not invasive. A rapid assessment of the invasive status of Eucalyptus species at 82 sites in South Africa (54 in the Western Cape and 28 in Mpumalanga) indicated that only Red River gum (E. camaldulensis) and flooded gum (E. grandis) are clearly invasive. Surveys were not undertaken in parts of the Western Cape known to be invaded by spider gum (E. lehmannii); the invasive status of this species is well known and is not contested. Red River gum has transformed long stretches of rivers and its importance as a major weed has been underestimated in previous reviews of alien plant invasions in South Africa. Most other species were naturalized. We recommend that projects aimed at clearing eucalypts should focus on riparian areas and nature reserves (where all eucalypts have deleterious effects), but that clearing projects outside these areas should only target species known to be invasive until such time as the invasive status of the other eucalypts (notably sugar gum, E. cladocalyx, and karri, E. diversicolor) can be ascertained with a greater degree of confidence. Publisher: Academy of Science of South Africa (ASSAf) -----Original Message----- From: Ecological Society of America: grants, jobs, news [mailto:[email protected]] On Behalf Of Paul Cherubini Sent: Monday, June 22, 2009 1:46 PM To: [email protected] Subject: Re: [ECOLOG-L] GM trees James Crants wrote: > My concern is not so much with the field test as with eventual > commercialization and widespread distribution of these trees > in places eucalyptus is not currently able to invade. James, the APHIS link I provided in my previous post http://tinyurl.com/mutlmu explained: "the Eucalyptus species used by ArborGen, Eucalyptus grandis x Eucalyptus urophyll is not considered invasive." "the GE hybrid trees are unlikely to produce seed, the trees are unlikely to hybridize with any nearby species, any offspring are likely to be sickly, and Eucalyptus grandis has difficulty establishing in the wild." "Eucalyptus grandis has been grown commercially in Florida since the 1960s and there has been no evidence that the species has escaped from cultivation and has become invasive. There is no reason to believe that adding cold tolerance to this genetic background would increase the likelihood that the species would become invasive." Paul Cherubini El Dorado, Calif.
