Quickribbon

Eucalyptus species identification: bark is not always enough

Share

By their fruits ye shall know them
Small tips on Eucalyptus Identification

Gustavo Iglesias Trabado Contact GIT Forestry Consulting
GIT Forestry Consulting - Consultoría y Servicios de Ingeniería Agroforestal - www.git-forestry.com


Eucalyptus
species determination is not just a matter of botanical interest. It can be quite important for its implications in regard to the different genetic pools (be them species, subspecies, provenances, or races) in cultivation. Important issues as cold hardiness (tolerance to winter frosts), growth rates (timber productivity) and physical and chemical properties of wood (timber quality) can depend on this variability, and hence be subject of forestry engineering.

Two forms of Eucalyptus delegatensis, Tasmanian Oak, growing in Galicia, Northwestern Spain. / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundoFig. 1: Two types of Ash ("Fraxinus wood-like") Eucalyptus: Tasmanian Oak

Telling Eucalyptus species apart can be difficult or confusing if differentiation criteria are based on a limited amount of variables. Bark type and characteristics can be one of the criteria for species identification, and can be considerably useful sometimes because some species are so strikingly different nothing else is needed. The chances of using bark successfully as "main criterium" are better for areas where eucalypts are introduced species, simply because the number of possibilities tends to be more limited than in a multispecific natural forest in Australia.


However, bark based identification can also be misleading. Pictured above (Fig. 1) you have two different types of eucalypts. If based on "bark only" criteria, maybe the first thought is they are two different species. But in fact, we are seeing two types of eucalypt belonging to the same species, but different gene pools. Both are Alpine Ash, a type of Tasmanian Oak (Roble de Tasmania).

Tasmanian Oak timber plantation in Galicia / Plantacion maderera de Roble de Tasmania en Galicia / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundoFig 3: Mature stand of rough barked Tasmanian Oak in the central plateau of Galicia, Spain

To the left
(Fig. 1), the classical form, rough stringy bark in the lower portion of the main stem, clean withish bark in the upper portion and in the main branches. In mainland Southeastern Australia it has also received the vernacular name of "White Top". To the right, a variant, rough stringy persistant bark almost to the very top and on the main branches too. The latter type is restricted to natural habitats in Tasmania.

So, what the botanists say about this? Let's read Dean Nicolle:


  • Eucalyptus delegatensis subsp. delegatensis (mainland Australia Alpine Ash) "Single stemmed tree 30 to 60 metres tall (...) Bark rough on the trunk up to 10 to 30 metres above ground level, moderately fissured and hard-fibrous, grey-brown; smooth above, ribbony, grey to pale grey over white"
  • Eucalyptus delegatensis subsp. tasmaniensis (also known as E. tasmaniensis) "Single stemmed tree 20 to 90 metres tall (...) Bark rough over most of the entire trunk, moderately fissured and stringy-fibrous, grey brown to red-brown, smooth on branches, pale grey over cream"

An encouraging bark-based diagnosis indeed. But, back to the initial point, given the high chances of confusing both these types of eucalypt with others of the Ash type (E. obliqua, E. fastigata, E. regnans sometimes), and the extra options given by the possibility for some of these species to produce hybrid seed when grown in close spatial relationship, bark can help in some cases.

Eucalyptus Identification, example of sample collection for species determination / Identificación de eucaliptos, ejemplo de recolecta de muestras para determinación botánica de la especie / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundoFig. 4: Example of botanical sample gathering methodology for accurate Eucalyptus species identification (Click to enlarge)

But the most important information to work out what Eucalyptus we are seeing and defining geographically the original gene pools is to be sourced from comparison of flower buds and seed pods (fruit capsules) (Fig. 4) for the case of adult trees.

Eucalyptus species identification / Identificacion de especies de eucalipto / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundoFig. 5: Example of mature Eucalyptus specimen bearing flower buds and seed pods (capsules), essential organs for accurate Eucalyptus species identification. (Click image to enlarge).

Of course, once these trees are able to lure us into patient observation of their flower blooms and their seed bearing capsules in order to get them identified, little is left before you start collecting the later to obtain seed, and attempt to raise some plants.
Eucalyptus species identification: bark is not enough / Identificacion botanica de especies de eucalipto: la corteza no basta / Eucalyptus botanical sampling / Flower buds, capsules, bark / Flores, capsulas, corteza / GIT Forestry Consulting, Consultoria y Servicios de Ingenieria Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics: Information Resources on Eucalyptus Cultivation Around the World


Eucalyptus species identification by botanical comparison of flower buds and fruits / Identificacion botanica de especies de eucalipto por comparacion de flores y frutos / Eucalyptus gomphocephala, Tuart / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundo




Eucalyptus species identification by botanical comparison of flower buds and fruits / Identificacion botanica de especies de eucalipto por comparacion de flores y frutos / Eucalyptus cladocalyx, Sugar Gum / Gustavo Iglesias Trabado / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundo



Eucalyptus species identification by botanical comparison of leaves, flower buds and fruits / Identificacion botanica de especies de eucalipto por comparacion de hojas flores y frutos / Eucalyptus kybeanensis, Kybean Mallee Ash / Gustavo Iglesias Trabado / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundo




Botanical identification of cold hardy hybrid Eucalyptus gunnii x nitens found in Denmark / Identificacion botánica del eucalipto híbrido E. gunnii x nitens resistente a las heladas localizado en Dinamarca / Martin Reimers, Eucalyptus Knowledge from Denmark, www.eukalyptus.dk / Gustavo Iglesias Trabado, Roberto Carballeira Tenreiro, Javier Folgueira Lozano y Asociados / GIT Forestry Consulting SL, Consultoría y Servicios de Ingeniería Agroforestal, Lugo, Galicia, España, Spain / Eucalyptologics, information resources on Eucalyptus cultivation around the world / Eucalyptologics, recursos de informacion sobre el cultivo del eucalipto en el mundo




Eucalyptus seed capsules, flower buds, immature seed pods, mature seed pods, senescent seed pods, capsule collection and seed extraction methodology / Semilla de eucalipto, flor de eucalipto, capsulas inmaduras de eucalipto, capsulas maduras de eucalipto, capsulas extramaduras de eucalipto y metodos para cosecha de semilla de eucalipto / Eucalyptus pauciflora seed / Snow Gum Seed / Semilla de Eucalipto de las Nieves / GIT Forestry Consulting, Consultoria y Servicios de Ingenieria Agroforestal, Lugo, Galicia, Spain, España, Europe, EuropaFig. 7: Different simultaneous stages of the reproductive cycle and eucalypt seed maturation process in a standing Snow Gum Eucalyptus tree.(Click to enlarge)


Eucalyptus seed capsules, flower buds, immature seed pods, mature seed pods, senescent seed pods, capsule collection and seed extraction methodology / Semilla de eucalipto, flor de eucalipto, capsulas inmaduras de eucalipto, capsulas maduras de eucalipto, capsulas extramaduras de eucalipto y metodos para cosecha de semilla de eucalipto / Corymbia calophylla seed / Red Flowering Gum Seed / Semilla de eucalipto de flor roja / GIT Forestry Consulting, Consultoria y Servicios de Ingenieria Agroforestal, Lugo, Galicia, Spain, España, Europe, EuropaFig. 8: Maturation stages for eucalypt fruits collected on Corymbia calophylla trees in a single visit, showing some of the internal organs within Eucalyptus infrutescences in each phase. (Click to enlarge)



Cold hardy Eucalyptus forestry seedling nurseries in Galicia / Viveros de planta de eucalipto resistente a la helada en Galicia / GIT Forestry Consulting, Consultoría y Servicios de Ingeniería Agroforestal, Galicia, España, SpainFig. 9: Examples of Eucalyptus seedling nursery stock for afforestation


Find a local expert to ID your Eucalyptus

If you have an unknown eucalypt around and you are able to collect and photograph samples of the key organs needed for identification, do not hesitate contacting GIT Forestry Consulting.

Eucalyptus species identification: Contact GIT Forestry Consulting / Identificación de especies de eucalipto: Contacte a GIT Forestry Consulting
Contact GIT Forestry Consulting / Contact Eucalyptologics / Contacto GIT Forestry Consulting / Contacto Eucalyptologics / Lugo, Galicia, Spain, EspañaContact GIT Forestry Consulting - Eucalyptologics

If you are in the USA and find it easier to post fresh samples to a local expert, you can also contact Dr. Matt Ritter, resident eucalypt hunter at the California Polytechnic State University.


EUCALYPTOLOGICS: GIT Forestry Consulting Eucalyptus Blog / Information Resources on Eucalyptus Cultivation Worldwide / Forestry Engineering, Eucalyptus Seed, Eucalyptus Plants, Eucalyptus Wood, Eucalyptus Honey, Eucalyptus Essential Oil, Eucalyptus Forests, Eucalyptus Plantations, Eucalyptus Timber, Eucalyptus Lumber, Eucalyptus Furniture, Eucalyptus Veneer, Eucalyptus Plywood, Eucalyptus MDF Board, Eucalyptus Cellulose, Eucalyptus Paper, Eucalyptus Biomass, Eucalyptus Energy, Eucalyptus Floristry, Eucalyptus Foliage, Eucalyptus Garden / Ingenieria Forestal, Semilla de eucalipto, Plantas de eucalipto, Madera de eucalipto, Miel de eucalipto, Aceite Esencial de eucalipto, Bosque de eucalipto, Plantacion de eucalipto, Muebles de eucalipto, Tablero de eucalipto, MDF de eucalipto, Celulosa de eucalipto, Papel de eucalipto, Biomasa de eucalipto, Energia de eucalipto, Ramillo Verde Ornamental de Eucalipto, Jardin de EucaliptoGIT's Eucalyptology Topics

Subscribe to receive EUCALYPTOLOGICS via RSS


© 2007 Gustavo Iglesias Trabado. Please contact us if you want to use all or part of this text and photography elsewhere. We like to share, but we do not like rudeness.

0 Comments by our readers :::


GIT's Eucalyptology Topics
Subscribe via RSS Subscribe via e-mail