Eucalyptus johnstonii - Tasmanian Yellow Gum
Tasmanian Yellow Gum. Fast growing green leaved tree, with beautiful bark, for damp soils. Good for arboretum, large garden, wider landscape. Call us for help in choosing your Euc. on 0751 526 1511
Why we like this variety:-
- Beautiful bark and foliage
- Fast growing, handsome tree
- Great for woodland and arboreta plantings
- Grows in wet ground
Botanical Name: Eucalyptus johnstonii MYRTACEÆ; Myrtle Family
Common Name: Tasmanian Yellow Gum, Johnston's Gum, Brown Gum, Yellow Gum!
Status: Evergreen Tree
Origin: Endemic to south-eastern Tasmania; it hangs out on montane forest sites such as Mount Wellington, Bruny Island and the Tasman Peninsula
Processing, shipping & dispatch
Nursery Notes 2020:
4 year old mature trees available in 20 litre pots
Young 5 litre stock ready again in 2020
Description, habit, uses and attributes:
A stately forest tree, tall, clean and straight; reaching about 30m in 60 years or so, at a very fast rate, under perfect growing conditions, less so elsewhere. Rare in the UK, E johnstonii has been successfully grown in Ireland since around 1910.
Related to the sensible, medium-sized E. subcrentulata and the miniscule shrubby E. vernicosa.....its a bit like Arnie Schwarzenegger and Danny de Vito in Twins! Wierdly, E. neglecta is also part of this botanical group of Eucs.
E johnstonii also produces quite good quality timber.
Lignotuber: E. johnstonii forms a lignotuber - which is a good thing. Should it be cut down by frost, man or beast, the tree will regenerate off this structure situated at the root plate.
How to use in the Landscape and/or Garden; how to grow, train and get the best out of it:
Good Specimen Tree for the wider landscape, arboretum collection or very large garden. Can be planted to quickly create a woodland canopy, whilst other trees are establishing. You then have the option to coppice or clear fell E. johnstonii as the woodland matures, or leave it to mature, as required.
Floral Art: coppices well and is vigorous enough to produce a good yield of cut foliage. It would be good to carry out commercial trials.
Firewood Production: could be good for log production provided E. johnstonii is grown in locations suited to its growing requirements. It certainly deserves to be trialled alongside E. nitens and E. denticulata.
Hedge-screens and Windbreaks: can be grown as a shelter-belt tree, provided soil conditions are met - see below for Planting Position.
Rural/Agricultural: as a green tree with chocolate bark, it looks comfortable in the countryside
Ecology: flowers are attractive to bees
Environmental: E. johnstonii can be grown as a coastal tree (in that E. johnstonii will tolerate growing near the sea), but foliage may become scorched by salt-laden winds.
Shoots 'n Leaves: Young shoots - apple green with bronze, may start off square in cross-section.
Juvenile foliage: round to oval leaves, glossy apple green
Adult foliage: beautiful apple green foliage, becoming lanceolate/falcate in shape as the tree ages, about 5-12cm long (2-5 inches)
Bark: Base of trunk is 'barky', but as the trunk rises, it becomes smooth and tactile, shades of milk chocolate, orange, caramel with deep lime green stripes. The bark peels annually like a Cadbury flake and shreds, sometimes hanging in ribbons in the branches.
Flowers: white flowers - three per umbel
Leaf Aroma: typical eucalyptol - quite strong
Rate of Growth: very fast at 2m+ per annum
Height in maturity, if left unpruned: about 20-30m over 60 years, eventually up to 50m in ideal conditions, less if deprived of water. If coppiced regularly, it will take on the size and shape of a species rose or coppiced Hazel Tree.
Hardiness: Hardy down to -8°C Most likely to be hardy down to -12 °C, judging by where E. johnstonii currently grows in the British Isles. South and West side of the UK where it is milder and also below the Gloucester/London line, also mild island climates.
Planting Position and Soil Preference:
E. johnstonii must be grow in full sun to thrive. It is happy in a broad range of pH states, from acid through neutral to alkaline, both poor and fertile soils. Good access to moisture is the key to success, so a mild, wet climate is great. In its native Tasmanian environment, it is subject to some waterlogging on peaty and sandy soils; grows mainly on poor soils, but does equally well on well-drained mineral soils. Soil types: light sandy, peaty, loamy and heavy clays, even those which are poorly drained.
E. johnstonii will tolerate maritime exposure.
I have read that it will grow in a bog garden.....surely this must be a serious bog garden (one the size of a small village!)
ESSENTIALS: Make like easier for you and your new tree. Plant with the mycorrhizal fungi product Rootgrow. Eucalyptus in particular have a special, lifelong relationship with their root fungi, the latter of which actively transport food and water directly into the tree roots. This helps your new Euc establish faster and more efficiently, especially in challenging soil types.
Origin of the name: Eucalyptus johnstonii: after Robert MacKenzie Johnston (1845-1918). Robert Johnston had a keen interest in botany and geology. He explored and collected extensively over most of the state of Tasmania, including traversing on foot some of the areas which are very rugged and inaccessible. He wrote over 100 papers and in 1888 published The Geology of Tasmania. (source Euclid)
Places where big specimens grow:
Mount Usher, Eire 1966 - 118ft, 111ft, 92 ft and 62 ft
Fota, Co. Cork, Eire 1948 - 80ft
Casa di Sole, Salcombe, Devon - 59ft planted 1955
Kinloch Hourn, Inverness-shire planted 1912, measures 125 ft. Also planted 1906, a tree measured at 105 ft in 1978
Hillier Arboretum, Ampfield, Hants, 72 ft measured 1984
Kilmur Forest Garden, Argyll, planted 1952, 95 ft
Castewellan, Co. Down, planted 1906, 85ft measured in 1983