Posted: Wed May 24, 2017 7:51 pm
by fooman
Hi Mark and Don,

The redwoods (Sequioa) at Whakarewarewa, Rotorua are pushing 72 m (236 ft) at around 110 years since planting [1]. Chris Earle considers these to be the tallest known horticultural (i.e. deliberately planted) conifers in the world [2]. The second tallest (known) planted conifer is a Douglas fir in a small plantation at Mt Peel Forest Estate, South Canterbury - BVP measured this at 69.6 m (227 ft) in 2013 about 140 years since planting [3]. I have LIDAR data for both sites that confirm those heights.

The tallest planted trees in the world are, however, Eucalyptus, not redwoods. There is a blue gum (E. saligna) in Magoebaskloof, South Africa, planted around 1910 that reached 81.5 m (267 ft) in 2013 [4]. A mountain ash near Dunedin, NZ (E. regnans) either planted in 1869, or possibly secondary growth from those plantings was measured by Sillet and BVP at 81.26 m (266.6 ft) in 2014 [5].

However, the record for growth probably stands with mountain ash in its native lands: Brett Mifsud measured a 87 m tree in Victoria, Australia that naturally regenerated after fires in 1926 - 285 ft in 81 years [6].

Cheers,
Matt

References:
1. https://register.notabletrees.org.nz/tree/view/1208
2. http://conifers.org/cu/Sequoia.php
3. http://conifers.org/pi/Pseudotsuga_menz ... ziesii.php
4. http://tree-addict.treesunlimited.co.za ... &Itemid=68
5. http://www.nzherald.co.nz/nz/news/artic ... d=11190768
6. http://victoriasgianttrees.weebly.com/tall-trees.html