Arborescence – making a tree

What is Arborescence? Arborescence is the term used to describe a plant as “tree-like”. And there are many plants that are arborescent , pines, eucalyptus, balga’s, palms and tree ferns to name a few. Plants like pines and eucalyptus are what fall into the “correct” definition of a tree.

To begin at basics a plant will grow by creating “primary growth” which makes the phloem and xylem that we are familiar with. A “tree” goes a step further by producing what is called secondary growth from the vascular cambium layer, although it looks more like a ring in cross section.  What this means is that secondary phloem and xylem is created, thickening and widening the stem.

Other plants however also achieve arborescence without using a cambium layer. Monocots like Xanthorrhoea, Pandanus and the palm family achieve this by different methods.

1.       Thick persistent leaf bases seen in Xanthorrhoea are one solution, by allowing your leaf bases to take the main support role this overcomes the need for a cambium layer.

2.       Pandanus achieve arborescent  status by growing prop roots to support an expanding canopy.

3.       The palm family Arecaeae, the most famous arborescent monocots use a different method, they use secondary thickening. But not from a single cambium layer. Rather the parenchyma cells within individual vascular bundles do. This is called anomalous secondary growth.

Now within the ferns there are two primary methods.

1.       The first is by strengthening the internal stem with hard sclerenchyma, this hardened tissue runs lengthways through the stem.

2.       The second method is by the growth of special fibrous, interlocking roots called a Root Mantle.  These roots can grow all up the stem and is widest at the base. An extinct tree fern species called Tempskya relied entirely upon it’s root mantle, reaching heights of 6m. This reliance on the root mantle also gave the plant a peculiar appearance (as seen above).

3.       Finally ferns also use persistent leaf bases.

Now we might think that is the end of it, but wait. I found another method used by the now extinct lepidodendrids. Lepidodendrids could grow as high as 55m and have a trunk diameter of 2m. they gained arborescence by enlarging and thickening their outer bark layer.

So there you have it all of the methods (that I could find) of becoming arborescent.

Moran, R,C. 2004. A Natural history of Ferns, Timber Press INC. London

Mary Bremner Bequest Grant Program – 2017 round

Large Grants

There were six applications which well exceeded the available funds of $36,000. Three applications were successful, and each received only part of the amount requested.

1. Wildflower Society of WA – Roadside Vegetation Sub-committee

Project title: Strategic Response to Clearing Applications



2. WSWA – Educational Sub-committee

Project title: Wildflowers Educational Outreach for Young People



3. WSWA – Plant Survey Programme

Project title: Plant Survey Data to NatureMap



Small Grants

There were four applications, again exceeding the available funds.

1. Wildflower Society of WA – Armadale Branch

Project title: Botanical Art Exhibition

To promote the WA native flora by exhibiting and selling artworks depicting WA wildflowers. The exhibition is timed to coincide with the WSWA State Conference and to celebrate the 60th Anniversary of the Society.


2. Wildflower Society of WA – Eastern Hills Branch

Project title: Blue Sky Festival.

Branch stall at the festival with displays, activities and plant sales.



3. Chittering Landcare Group

Project title: Enhancing the Wildflower experience in Chittering.

Project title: To prepare and print a Self-guided tour of Blackboy Ridge Reserve in the Chittering Valley and the making of, or purchase of, a perspex box to store them in at the site. (Project part funded).


Blue Sky Festival


On Saturday 17th March, the Eastern Hills Branch participated in the Blue Sky Festival at Mundaring. Held in and around Sculpture Park,. the festival focussed on sustainability and environmental issues. Our display had a theme of Wattles- get rid of the weeds and grow local. With the help of photographs and actual foliage samples, we were able to demonstrate the difference. We gave away propagation kits comprising pre-treated acacia seeds- we had A.alata, A.celastrifolia, A.pulchella and A.dentifera- and starter pots containing seed raising mix. These were popular and quite a lot of people already knew of the proliferation of some of the eastern states wattles such as Flinder’s Range Wattle.


Acacia dentifera

The festival had many community groups participating such as the Naturalists, Kenyana, St Barbe’s Nursery and a range of talks on nest boxes, bushfire preparation, battery storage and revegetation. The Tiny House was very interesting as was the entertainment from the Junkadelic band! The festival was supported by The Mary Bremner Small Funds bequest via our branch.


Giving away acacia propagation kits


Blooming Biodiversity Video

Here is a tone poem of visual images of Albany and the South West – just to get you in the mood for the ANPSA National Conference in 2019.  We’ll be adding in more flower footage as the season progresses, so that it is representative of the scenery at that time of year.  Link here.  Enjoy!

Blooming Biodiversity wildflower slideshow

Here are some amazing Western Australian wildflowers which, if all goes well, you might see on the ‘Blooming Biodiversity’ Conference tour. Photos by renowned artist and Society member Margaret Pieroni, who designed our Conference logo. See slideshow here.

While you are at it, why not register for Conference updates?  Or just keep checking back on our website, under the ‘ANPSA’ menu item at the top right of the page.

Newsletter now available – Members Only

The Wildflower Society of WA newsletter (February 2018, Vol 56 No 1) has now been published electronically.  All members are entitled to view and download the electronic newsletter.  The printed newsletter should be posted to those who have requested a hard copy (no green discount) in the next several weeks.

You may view the newsletter online by going to the ‘Members’ tab at the top of any page of the WSWA website, then choose ‘Newsletters’ at the side of the page.

Or link to the newsletter page here.

If you are having trouble logging in, it may be that your membership is overdue.  Please ring Perry House to enquire during office hours, or email at any time.

Front cover: Helena and Aurora Range. Photo: Brian Moyle.  More photos of declared rare flora Tetratheca paynteri and Leucopogon spectabilis from the Helena and Aurora Range in the inside cover.

Darling Range NatureBase

Members of the Darling Range Branch of the Wildflower Society and the Naturalists Club have coordinated with Michael and Lesley Brooker to produce a ‘Darling Range Naturebase’ document which is a guide to plants and animals to be found in the area. You are free to download this wonderful reference guide at or link here.  For more information about Darling Range Branch of the Wildflower Society, check out their page here.

Thank You, Tasmania

Thanks to the Australian Plant Society Tasmania for a wonderful conference!  They did a brilliant job and set a high standard for us to follow in 2019.  Wonderful tours, fantastic speakers, and even the weather was spectacular.  Thanks from all of the Western Australian attendees !

Congratulations Michael Morcombe AM

Michael was appointed a Member of the Order of Australia in the Australia Day 2018 Honours list … ”for significant service to conservation and the environment in the fields of natural history and ornithology as a photographer, illustrator, and author“.

Michael is a foundation member of the Wildflower Society of WA, Armadale Branch (since March 1961), past branch president and patron (2008–2016), and since 2015 an Honorary Life Member of the Society. Michael – along with wife Irene – has published approximately 40 books plus many other publications. His photography, flora and bird illustrations, written works and ‘Australian Birds’ smartphone app have won many awards both nationally and internationally. Being made a Member of the Order of Australia is a well-deserved recognition of his endeavours in the field of natural history.

Thank you, Minister Dawson

Our heartfelt thanks to WA Environment Minister Stephen Dawson, who has announced the final outright rejection of mining of the Helena Aurora Range and the intention to create a Helena Aurora Range national park.

We invite our members to personally thank Minister Dawson, and to look at the proposal for a national park prepared by the Wildflower Society, the Wilderness Society, and the Helena and Aurora Advocates.

Download the Helena and Aurora National Park Proposal here (3mb).