Tallest living hardwood tree
Centurion, Australian mountain ash, Eucalyptus regnans
Australia ()

The world’s tallest hardwood tree (and angiosperm) is currently an individual of Australian mountain ash, or swamp gum (Eucalyptus regnans) known as Centurion. Remarkably, its existence was unknown until October 2008, even though it is located just a few kilometres from Tasmania’s famous Tahune Airwalk. When initially climbed in 2009, the height was 99.60 m (326 ft 9.3 in) tall - 100.31 m (329 ft 1.2 in) to the low point of ground and 98.89 m (324 ft 5.3 in) to high point of ground. The most recent confirmed tape drop height was 99.82 m (327 ft 5.9 in), measured in 2014 by Steve Sillett. Ground-based measurements suggest that the tree had surpassed 100 m (328 ft) by 2018. The devastating 2019 Tasmanian bushfires killed many of Tasmania’s largest trees, and the base of Centurion was moderately burned, although the treetop was initially still alive. In 2014, the tree had an estimated aboveground dry mass of 122 metric tonnes (135 US tons) and 541 kg (1,193 lb) dry mass of foliage.

A close contender for this record is a yellow meranti (Shorea faguetiana) located in Sabah, Malaysian Borneo. On 6 January 2019, the tree was climbed by Unding Jami of the Southeast Asia Rainforest Research Partnership and measured by direct tape-drop to be 98.53 m (323 ft 3.1 in) tall - the average from 100.80 m (330 ft 8.5 in) tall to the low point of ground and 96.26 m (315 ft 9.8 in) to the high point of ground. The tree has been named Menara, the Malay word for "tower", and is nevertheless the record holder for tallest tropical tree.

The tallest living tree overall is not an angiosperm but a gymnosperm (vascular plants that lack flowers and fruit): the superlative specimen of Sequoia sempervirens, nicknamed Hyperion, is located in Redwood National Park in California, USA. The coast redwood, a type of conifer known for its lofty stature, was discovered by Chris Atkins and Michael Taylor (both USA) on 25 August 2006 and, as of 2019, it stands 116.07 m (380 ft 9.7 in) tall.

Globally, eucalypts are also the world’s tallest planted trees. Direct tape-drop has confirmed an 82.25-m-tall (269-ft 10.2-in) E. regnans near Dunedin, New Zealand (measured in 2018), a 79-m (259-ft 2.2-in) E. saligna near Polokwane, South Africa (measured in 2013) and a 72.9-m (239-ft 2.0-in) E. diversicolor near Coimbra, Portugal (measured in 2015).