http://www.research..../1998/clone.htm
Ancient clone
Lomatia tasmanica: the oldest clonal plant on the planet
Botanical history was made in 1998, when a team of scientists from the School of Plant Science at the University of Tasmania, and the Department of Environment and Land Management in Tasmania (Jasmyn Lynch, Jayne Balmer, Dr Greg Jordan, Dr Jocelyne Cambecedes, Richard Barnes and Dr René Vaillancourt) made botanical history when they identified the oldest living plant individual known to date.
Lomatia tasmanica (common name King's Holly), a member of the Proteaceae family, is known by only one population that grows along creek gullies in remnant rainforest in the World Heritage area of Southwest Tasmania.
Isozyme analysis has revealed that it possesses zero genetic diversity (that is, all living plants of the species are exactly the same), whereas a closely related species, Lomatia tinctoria, which also propagates vegetatively, has a normal level of genetic diversity. Lomatia tasmanica has a triploid chromosome number which explains why it appears to be sterile - it flowers but never forms mature fruits - and shows little morphological variability. This accumulated evidence strongly suggests that the entire species is a single clone that propagates vegetatively.
The L. tasmanica clone spans 1.2 km which makes it the second longest plant in the world after the box-huckleberry clone in Pennsylvania which is reported to be 2 km in length.
Prior to the Tasmanian discovery, the oldest reported plant clone was the box-huckleberry at 13,000 years, while the oldest living tree is believed to be a bristlecone pine in Arizona which has been dated at 4,700 years.
The size of the clone, and the observation that vegetative propagation is likely to be very slow in the cold climate of Southwest Tasmania suggests that L. tasmanica is also extremely old. Fortunately, its longevity can be substantiated. Fossil leaf fragments genetically identical to the living L. tasmanica were found in a fossil deposit 8.5 km from the extant population and are presumed to represent the same clone. Radio-carbon dating has established the age of the fossils at 43,600 years, so it appears that genetics and paleobotany have collaborated to establish that Lomatia tasmanica is the oldest living plant individual known to date.
