Dry rainforests of Mt Berryman. Photo by Paul Grimshaw.
To most people, the mention of the word rainforest conjures up visions of lush green tall vegetation festooned with epiphytes (orchids mosses and ferns), numerous vines, palms and ferns. In South East Queensland (SEQ) in places such as Lamington, Springbrook, Tamborine and Mt Glorious these types of luxuriant rainforests are commonly encountered.
However there are other rainforests that are not as lush and tropical-looking as these types, one type in particular is ‘dry rainforest’. Though not as moist as other types of rainforests, dry rainforests can easily be distinguished from other surrounding vegetation such as open eucalypt forests and woodlands, due to their dark green colour and the tight, compact crown seen from a distance.
Dry rainforest is a term used to describe vegetation, where rainfall is low because of topographic conditions (sometimes referred to as rain-shadow). Other terms used to describe variants of dry rainforests are dry vine forest, dry vine scrub, softwood scrub, Brigalow scrub, bottletree scrub, Hoop Pine scrub and microphyll (small-leaved) vine forest. At the drier extreme these vegetation communities sometimes grade into what is known as semi-evergreen vine thicket, or SEVT for short. A feature of some dry rainforests is that many of their tree species have the capacity to shed most or all of their leaves as a strategy to survive long periods of drought (this is where the term semievergreen is derived from). Compared to wetter types of rainforest in higher rainfall areas the dominant canopy height of dry rainforest is considerably lower.
In most cases dry rainforest has a lower canopy layer plus an upper layer of emergent trees rising above the canopy. The lower canopy usually consists of 10-30 tree species and the upper layer consists of scattered taller trees. Common emergent trees include Hoop Pine, Lacebark (Brachychiton discolor), Rusty Fig (Ficus rubiginosa) and Crows Ash (Flindersia australis).
Due to past clearing, dry rainforest remnants are considerably diminished and the remaining patches are still under further threat from vegetation clearing, grazing, wildfires and weed invasion. In times past, dry rainforests were cleared for grazing and other types of agricultural use in the mistaken belief that the soils, that they were occurring on, were more fertile and nutritious than the soils supporting other drier types of surrounding vegetation such as eucalypt forests and woodlands. In most situations this was untrue as once the dry rainforests were cleared and utilised, for whatever agricultural activity was needed, the fertility was quickly depleted. This is because the fertility and nutrients were stored in the top few centimetres of soil and ground litter, while the dry rainforest still existed.
While some of the tree, shrub and vine species occurring in dry rainforests are confined only to dry rainforests (e.g. Narrow-leaved Bottle Tree, Brachychiton rupestris; Leopard Ash, Flindersia collina; Small-leaved Scrub Ironbark, Bridelia leichhardtii) many other species also occur in other moister rainforest ecosystems (e.g. White Cedar, Melia azedarach; Guioa, Guioa semiglauca; Hairy Birdseye, Alectryon tomentosa). These species that occur in both dry and wet rainforests often occur as pioneers (early successional) plants in the moister rainforest types.
Climate change is likely to increasingly affect our moister rainforest types in SEQ with many of the moisture dependent plants becoming stressed during long dry periods and possibly facing local extinctions. This is where many species of dry tolerant plants found in dry rainforests will be most likely to replace them and help the less drought resistant rainforests to continue to survive.
Once established, many dry rainforest plants are more likely to cope with lowering annual rainfall and warmer temperatures as a result of climate change. It is therefore suggested that the many plant species found in dry rainforest be considered for regeneration projects, or in rainforest areas where loss of moisture dependant species is already occurring.
Equally, it is extremely important to continue to protect, manage and maintain the integrity of all remnants of dry rainforests. Dry rainforests contain a good number of threatened and uncommon plant species and a large percentage of the Regional Ecosystems, in which they are represented, are listed as Endangered under Queensland legislation.
Some of the greatest threats to our SEQ dry rainforests currently are introduced weeds, wildfires, grazing and a lack of funding streams for active conservation management. Some of the worst weed threats include vines such as Madeira Vine, Cat’s Claw Vine, Climbing Asparagus and Glycine. Weedy shrubs and trees include Lantana, Chinese Celtis, Tree Pear, Ochna, Coral Berry and Privet. Weedy grasses include Green Panic, Guinea Grass, Rhodes Grass and Broad-leaved Paspalum.
Introduced grasses are a major threat to dry rainforests as the grasses grow quickly and produce huge amounts of biomass. When dry, this biomass is highly flammable. If these grasses become established on the edges of dry rainforests, when a fire comes through, the fire will kill many fire-sensitive rainforest plants. Fire will also cause the dry rainforest to contract in size, getting smaller and smaller until it is no-longer a functioning ecosystem.
Introduced grasses can also find their way deep into a dry rainforest patch. This often occurs during drought conditions when stock is allowed to enter the dry rainforest areas for shelter. Drought causes many rainforest trees to drop their leaves making the canopy more open. During these dry periods the grass seeds contained in the stock droppings, are able to germinate, and the grasses become established, thrive and eventually cure off leaving a highly combustible fuel load within the rainforests. In such scenarios, fires can encroach deep within the dry rainforest reducing the health of the ecosystem.
If you are lucky enough to have dry rainforest on your property, please do what you can to protect it from wildfires and introduced grasses.
Article by Paul Grimshaw
Land for Wildlife member
Mt Crosby, Brisbane
Good Afternoon,
Thank you for all the above.
We have dry rain forest vegetation, hoop pine, crows ash, on our property on the western side of Lake Wivenhoe at Belz Road Coal Creek via Esk. I am interested to know if there are palm species suitable to grow here.
No
I’m wondering if any cycads could grow there and if they would interest you. Although not related they are somewhat palm-like but not very tall, and very slow-growing,
For palms you could give the Australia Cabbage Tree Palm (Livistona Australis) a try – generally these tend to grow in swampier/wetter areas but they seem to be reasonably drought tolerant once they are established – though they may need some looking after until they mature, But if you can find more sheltered areas that is probably the most suitable spot for them.
If you are going to plant these I’d suggest to try and source the plant from a local rainforest supplier that uses local seed stock – its a common enough palm to source from generic nurseries but i’m not sure about the genetic diversity of these. A specialised rainforest nursery should be taking into consideration genetic diversity in seedlings.
I am very keen to plant such trees associated with SEVT on my backyard. In my opinion many of the plants I have observed in the dry scrub remnants are far more attractive then the exotic ornamentals most people stick in their gardens. I would like to know if there is any where I can:
1. Acquire these plants as tube stock with out setting up my own nursery for propagation.
2. Acquire a plant species list of all plants common to SEVT in SEQ.
Crows nest Community Nursery connected with Toowoomba shire Council has some of the species, I understand..
I can still remember when i was younger, up visiting Grandma at Toowoomba, and going down into Redwood Park via the gully. Privit was a major problem shading out forests, back then i took a handsaw with me and cut it down in patches. I can recall the dry rainforest with its vines, though it was invested in parts with i believe cats claw creeper, i havent been back there for years, so I wonder if local groups cleared the creeper
We live next to Mt Chinghee and have successfully encouraged dry rainforest regrowth on our property for years. I planted a couple of Owenia cepiodora last year but lost them to the extended drought and want to try again soon. W’ve cleared a lot of lantana and continue doing so but have left some at the forest edge for black-breasted button quail and regent bowerbirds. We have Eucalyptus tereticornis with Themeda understory win the more exposed slopes, and had been gradually giving the Themeda the competitive edge over the bladey grass and Rhodes grass that are also there.
Hi Ronda. Good on you. Sounds like fabulous work you are doing. If you are not already a member of Land for Wildlife, you may wish to consider joining!
I am a member, and we’ve also had a Vegetation Conservation Covenant placed on our land
Hi . I work as a proffessional bushregenerator. I am based in lismore NSW. One of my projects is restoring a heavily degraded old quarry adjacent to a very high conservation value dry rainforest remnant ( araucaria / drypetes suballiance ) (contains the only known occurance of triflorenza cameronii in NSW ). It is basically a project to extend rotary park . I also work in rotary park as well . Weeds , fruit bat , ibis and other human encroachment issues are a constant challenge . Im sure u can relate to some of them . I just want to say i am happy to hear about the dry rainforest and vine thicket restoration projects in south east QLD and would like to visit one day and check it out . It would be an interesting challenge to identify some of the species that dont occure south of the border . Keep up the good work .
Thanks Alex for your comment and its is great to hear of your good work down in northern NSW too. Cheers!
Dry rainforest is a silly name. It is oxymoronic. Why dont you call it dry jungle?
Toowoomba Redwood Park on the slopes of the Toowoomba Range is a magnificent example of a Dry Rainforest, It is maintained twice a week by a group called Friends of the Escarpment Parks. They work there Monday and Thursday mornings from 7 to 10.30. To date they have rehabilitate 32 hectares of the parks 250 hectares in partnership with the Toowoomba Regional Council.
Last year these volunteers discovered that the Council wants to run four mountain bikes trails straight through the heart of the Park to capitalise on the Australia wide Mountain Bike Sport. In so doing South East Qld risks losing what for the past 100 years has been a bird conservation paradise home to the rare Black Breasted Button Quails, Rufus Fantails, Spectacle Monarchs and Powerful Owls.
The Darling Downs Environment Council is currently running the Save Redwood Park campaign. Find us on Twitter or Facebook. Checkout Scott McPhies interview from Birdlife Australia on the impact of Mt Bikes on Redwood Park birds. Also you can donate at chuffed.com to help fight this decision.
That is good to hear Sandy, i was concerned about Redwood Dry Rainforest, as when i was younger and visiting grandma over a decade ago, weeds particularly vines were impacting on it, i was very upset how they bulldozed fire trails through the rainforest. It needs care as its quite a large patch of dry rainforest. Leave the trails for Jubilee park instead. Instead of this the council can invest is keeping it weed free. I will look at the links you mentioned, cheers Sam
I have to see Redwood Park again, i was a frequent visitor when younger.
I live in the Gold Coast hinterland, The western side of the rain near home has dry rainforest with hoop pine as the emergence species its under threat from the homes on the eastern side dumping garden waste.
I have a,small market of native trees…I have become aware of rain and dry Forrest trees..I am finding that I can get plantly of rainforest trees, struggling to find dry one or Evan a list of name, sixe and so forth thank you. These are for the Lockyer Valley Area, Qld.
Hi Cozza. There are some good factsheets on certain dry rainforest ecosystems, with species lists, on the LfWSEQ website under Resources > Ecosystem Factsheets.
https://www.lfwseq.org.au/wp-content/uploads/2017/06/RE-Fact-Sheet_12.8.21_HLW.pdf
https://www.lfwseq.org.au/wp-content/uploads/2017/06/RE-Fact-Sheet_12.9-10.15_HLW.pdf
We have 67 acres at Mount Beppo (half way betwen Esk and Toogoolawah) and have planted over 2000 cabinet timber trees over time. – lots of the Flindersias, White Beech, Silky Oak, Grey Box, Hoop Pine and many others, trying to create our own dry rainforest. Our property is now very beautiful and a haven for a host of different birds. Always open to advice as to what other trees we could plant.
Trisha at Didohama Suri Stud.
Hi Trisha. Thanks for sharing and congratulations on planting all those trees and creating your own dry rainforest. There is more information about the various dry rainforest ecosystems on these factsheets at https://www.lfwseq.org.au/ecosystem-factsheets/
I agree that ‘Dry rainforest’ doesn’t appear to be the most appropriate title for these drier types of rainforests. There are other names given to describe these plant communities such as Dry vine forest, Dry vine thicket, Dry vine scrub, Bottle tree scrub, Softwood scrub and Semi-evergreen vine forest/thicket, However the title Dry rainforest has been used as a title used for the drier types of rainforests by some of the top rainforest ecologists in Australia in the book ‘Rainforest Trees and Shrubs’ by authors Gwen Harden, Bill McDonald, John Williams and Alex Floyd. Therefore who are we as mere mortals to question the use of the Dry rainforest title.
A great source of native rainforest plant species and a wide range of other native plant species are the Native Plants Queensland seasonal plant sales held every year at the Belmont Range Complex, Samford Valley Showgrounds and the Rosewood Showgrounds west of Ipswich. The next Native Plant Sales are happening at Rosewood very soon on Saturday 28th October 9.30am – 3.00pm. So get yourselves there and join the crowds in buying a wide range and variety of great plants at bargain prices.