Leucaena leucocephala: friend and foe

· Guest post by Dave Pratchett ·

Goondaloo Creek Landcare site became the focus of my Landcare volunteering in 2019, soon after we moved to Townsville. Assisting with weed control and watering in the newly planted section opposite Tech NQ, I could look upstream to an area rejuvenated through years of sustained effort. But downstream was dominated by leucaena trees, heavy with seed pods. From a local Landcare perspective, these trees are a major foe.  

I cannot help but feel partly responsible for the invasion by this particular weed species, because early in my career in Australia, I worked hard to grow it!

The establishment of leucaena as a cattle fodder in Australia was led by Dr Ray Jones and is a fascinating story. The plant contains toxic mimosine and Ray proved that ruminants can tolerate this only when they have a very specific gut bacterium; he identified the bacterium (which was then named Synergistes jonesii) and by sheer persistence, brought samples to Australia.     https://csiropedia.csiro.au/leucaena-toxicity-solution/

In the 1980s I worked with Ray running trials in the Ord River Irrigation area to determine the optimal stocking rate and plant density for finishing cattle bred on Kimberley stations. Although various problems reduced marketing potential, the value of leucaena as a fodder crop was proven spectacularly as we reached 1500 kg (5 head) per hectare. https://researchlibrary.agric.wa.gov.au/cgi/viewcontent.cgi?article=3401&context=journal_agriculture4

I noted “Leucaena seedlings are difficult to establish under dryland conditions and under irrigation. Germination and emergence are usually not a problem, provided the seed is treated with hot water to break dormancy. Once the seedlings are two to three centimetres high, growth slows down and weeds can compete with and smother them’.

No one has boiled the seeds of the leucaena plants which have now invaded much of Northern Australia and they establish particularly well along river banks, and in cleared areas. The species is however a useful fodder plant cultivated by cattle producers in parts of Queensland, including our local area. It is also a ‘friend’ to many in  its native South America and countries such as Indonesia and India, where leucaena is a valuable dryland fodder and has an amazing variety of other uses, including human nutrition. http://archive.unu.edu/unupress/food/8F163e/8F163E08.htm

So, like all weeds, leucaena is a problem only when it invades areas where it is not wanted. It is certainly not wanted on our Landcare sites and I look forward to spending my later years in Australia working with Coastal Dry Tropics Landcare volunteers to reduce the damage it has caused here.

Birdwings and butterfly vines

· Guest post by Malcolm Tattersall ·

Many of us know that we should grow a particular vine to attract Birdwing butterflies to our gardens but just what the vine is called, and which butterflies rely on it, are recurring questions.

Very briefly, the caterpillars of one group of Swallowtail butterflies feed exclusively on one group of closely-related plants. The butterflies are the Troidini, a “tribe” (in scientific language that’s a level between “family” and “genus”) of Swallowtails (Papilionidae) and the plants are the Birthworts (Aristolochiaceae).

Our Troidini are the Clearwing Swallowtail (Cressida cressida), Red-bodied Swallowtail (Pachliopta polydorus) and all of the Birdwings (Ornithoptera species). The Aristolochiaceae we’re interested in are in the genus Aristolochia, or used to be. Many of them are commonly known as Dutchman’s Pipe vines.

Everything gets messy at the next level of detail. If you want to avoid that but still attract the butterflies to your garden, this is all you need to know:

  • Aristolochia acuminata, also known as Aristolochia tagala, is a food plant of all our Birdwing species and of the Red-bodied and Clearwing Swallowtails, and it is the vine most widely grown in Townsville gardens. It is sold by the Bush Garden Nursery as Aristolochia acuminata.
  • Richmond Butterfly Vine, Pararistolochia praevenosa, is a food plant of all Birdwing species and the Red-bodied Swallowtail. It is the vine widely promoted in SE Queensland as the “birdwing butterfly vine.”
  • Dutchman’s Pipe Vine, Aristolochia elegans also known as Aristolochia littoralis, is the main one to avoid. It’s an exotic, introduced from South America, and it poisons our butterflies. The adults lay their eggs on it but the caterpillars rarely survive.
  • If you stick to the Latin names, there should be no confusion about which vine is which.‬

One reason that the questions never seem to go away is that there have been changes in the scientific names of both the vines and the butterflies. Another is that “common names” (the names in English) are used inconsistently to cover several similar species. And, finally, there are several other native vines which are food plants for one swallowtail butterfly or another. All of these are discussed in the longer original version of this article on my blog “Green Path”.


Guest post by Tim Doolan

Worm farms have become all the rage recently, and I’ve been lucky enough to have received one for my birthday.

For the uninitiated, worm farms are a container where you throw food scraps and provide an environment for particular types of worms to flourish. In return they give you worm juice and castings to purportedly make your soil healthier and plants grow better. It seems to make sense, but I’m yet to experience this in practice.

The most popular at the moment as far as I can tell is the Worm Café, which is what I’ve got. The photo above shows the worm farm stack positioned in my downstairs laundry. The photo below shows the inside, covered by a hessian sack.

People also commonly make their own worm farm using something like an old bath tub or old wheelie bin.

The particular types of worms aren’t your regular earthworms. They are special little gutses who eat a lot faster and break down waste into useful garden products. There’s various types, I have read Blue Worms (Perionyx excavatus) being well suited to warm climates but there’s differing opinions, there are also cool sounding names like Red Wrigglers and African Nightcrawlers. The photo at the top of this post shows the wrigglers at work in my worm farm.

Whatever the worm, they break down waste and produce worm juice and castings. It’s not exactly fertiliser but more about the microbes that break organic material into usable nutrients and well-structured soil for plants to thrive. Worm castings are basically the same sort of thing as worm juice but in solid form to also add bulk and structure to the soil. The goods – castings from the bottom bin – can be seen in the photo below.

I’ve had the worm farm for about 10 months now, so I’m hardly an expert, but these are a couple of things I’ve found to be of some relevance trying to set up a worm farm in our climate:

Land planarian – These worm/slug flat looking things eat your worms and are apparently rife in the tropics. I had a bunch that were eating my worms so picked them all out by hand and haven’t seen any since. I think they got in there in the first place from contaminated worms.

Ants – From time to time I’ve had ants try to set up a nest or steal food, but it’s usually because it’s a bit dry in there. Add water and wah-lah, they are gone. Also helps to cover the top of the food with a hessian sack.

Acidity – There was a stage at the beginning where it smelt a bit like a dodgy seafood basket the second time around, but that was because I was adding too many acidic things (oranges, lemons, onions). Once I stopped doing that and added some alkaline crusher dust things balanced out and the smell went away. Your worm farm should magically smell pretty much like nothing, or damp soil if you really put your nose in there.

Temperature control – This was a big problem until I found a suitable place in the dark out of the wind. The worms tried to escape or retreated to the wettest coldest corners of the container away from the food (and their job!) to try to not get cooked in the heat.

Other creatures – there’s a lot of other life in my worm farm, little crustaceans, crawly things, but it all seems to co-exist with the worms just fine.

Lorikeet with Black Beans

· Guest post by Malcolm Tattersall ·

No, this isn’t a recipe.

The Black Bean in my title is a local tree, Castanospermum australe, and you wouldn’t want to cook with its seeds because they are too too big and too toxic. Two of our neighbours in Mundingburra have well-grown specimens and I am simply taking this opportunity to share an October photo of its attractive flowers.

I know the tree as a local species but didn’t realise just how limited its range was until I looked it up: a patchy distribution along our tropical coast, and that’s all. Nor did I realise just how high it can grow – forty metres. (I wonder if our neighbours know, but I’m not going to tell them in case they start worrying and get their trees chopped down. We need all the trees we can get, and these are very beautiful.)

Black Bean timber is both beautiful and rot-resistant. The latter quality has seen it used for fenceposts, but that seems a terrible waste when it makes such attractive furniture.

According to the Australian National Herbarium, “it is native to coastal rainforests and beaches in Australia from around Lismore, New South Wales to the Iron Range, Cape York Peninsula, on the Queensland coast and 160 km west to the Bunya Mountains. It grows in moist, fertile, well-drained soils on terraces on the side of mountains or along the banks of rivers and streams.” It also grows in many Townsville primary school grounds, where the heavy seed pods tempt children into mischief.

Flowerpot snakes

· Guest post by Malcolm Tattersall ·

We were moving lots of pot-plants last October, planting out many of them and re-potting others, and one day we disturbed a few strange worms in the process  … or so I thought. All of them were typical worm size, perhaps 8 – 12 cm long and shoelace-thick. Most were black, but one was a delicate lilac colour; and they were all very active, wriggling for their lives until they could vanish into the soil. When I handled them, I found them very dry and slippery, which puzzled me. It didn’t intrigue me enough to stop work, however, or I might have trapped them for closer observation and discovered that they weren’t worms at all but snakes.

A reptile chart at the Bush Garden Nursery alerted me to the fact that I had been playing with Flowerpot Snakes, Indotyphlops braminus.

The species isn’t native to Australia, but is a fairly recent arrival from SE Asia, probably arriving in boat cargo. Like the Mourning Gecko its invasiveness is enhanced by the fact that it is parthenogenetic, i.e., all individuals are females and a new population can be started by a single stowaway. It was first noticed in Darwin and the Torres Strait, and it was first reported in Townsville in 1998. It is now found in scattered populations from (at least) the Pilbara to Brisbane.

I was ready for the next one we found and was able to get the photo above (I have to say she wasn’t the easiest portrait subject, being very dark, quite small and quite uncooperative.)

She (all of them are female, remember) was about 12 cm long, which means she was close to fully grown. Her head was just slightly rounder (blunter) than her tail, although I wasn’t really sure which was which until I saw her tongue flicking out since the eyes are almost invisible and I couldn’t see the mouth at all. The scales are tiny, shiny and close-fitting, obviously designed to help her slip through the dirt but making her difficult to hold on to without injuring her.

Wikipedia says:

Adults measure 2–4 inches (5.1–10.2 cm) long, uncommonly to 6 inches (15 cm). It is the smallest known snake species. The head and tail are superficially similar as the head and neck are indistinct. Unlike other snakes, the head scales resemble the body scales. The eyes are barely discernible as small dots under the head scales. … Coloration ranges from charcoal gray, silver-gray, light yellow-beige, purplish, or infrequently albino, the ventral surface more pale. … Behavior ranges from lethargic to energetic, quickly seeking the cover of soil or leaf litter to avoid light. … The tiny eyes are covered with translucent scales, rendering these snakes almost entirely blind. The eyes cannot form images, but are still capable of registering light intensity. … Their diet consists of the larvae, eggs, and pupae of ants and termites.

The Wikipedia page also has the best collection of names for the species. The only one which might cause some confusion is Ramphotyphlops braminus, which is the name given to them by Steve Wilson in his Field Guide to Reptiles of Queensland and JCU on their wildlife pages. Australia does have its own blind snakes, all in the genus Ramphotyphlops, and Queensland is home to 18 species. They are all bigger than the Flowerpot Snake (up to 400 mm) but are otherwise very similar: non-venomous, subterranean predators of ants and termites.

This article first appeared on Green Path, Malcolm’s wildlife and environment blog, in October 2019.

Water chestnuts at Wongaloo

 • Guest post by Carolyn Osterhaus •

I had heard about the Wongaloo wetlands from the Birdlife Townsville people. I also found out, to my chagrin, you can only go there on a tour. How serendipitous that the celebration of National Landcare Week in September included a bus tour to just this spot.

The Wongaloo trip was bracketed by an informative walk through the Bush Garden in Mundingburra, showcasing nursery manager Christine Dalliston’s encyclopaedic knowledge of the plants there. People found it difficult to tear themselves away for a bus which didn’t show up, then did. The day ended at Morratt’s Pit, a site revegetated by Lower Burdekin Landcare Association.

You’d be amazed at how many people have never visited Wongaloo wetlands, even people who live nearby. The bus driver couldn’t talk enough about his first-time visit. Seeing thousands of birds on water in a region where it rarely rains was a great treat. As the bus driver said, it made the Town Common look like an airport.

The Wongaloo Regional Park sits adjacent to the Bowling Green Bay Ramsar site and is managed jointly by the non-profit Wetlands and Grasslands Foundation, a public company and registered charity, and Queensland’s Parks and Wildlife Service. The Foundation received a grant to remove weeds lantana, pink bauhinia and candle bush from the 50 hectare site. Several kilometres of fencing were erected to help manage stock and control weeds.

Wongaloo wetlands support the largest concentration of brolga recorded in Australia: around 12,000. It is a breeding site for both brolga and magpie geese. The main reason is the bulkurru, botanical name Eleocharis dulcis, common name Chinese water chestnut. Bulkurru forms dense beds during the wet season then dies back to tubers as waters recede during the dry. Birds breed during the wet then dig into the mud to harvest the tubers in the dry. Wongaloo is also an important habitat for waterbirds and seasonal fish. Freshwater fish move onto the site from streams during the wet season to spawn.

Water at the site originates from three sources. First, runoff from the Mt Elliott Range. Second, a massive sand ridge deposited over thousands of years by the Burdekin River collects and stores rainwater, releasing it gradually into the swamps. And third, occasional flooding of the Haughton River.

Weeds are kept in check by grazing cattle, carefully monitored. Lakes were fenced in such a way that cattle could not just wander up to them and damage shorelines. Feral pigs are a problem. In the past Conservation Volunteers have helped with weeding. According to Christine: “The other really important thing in managing Wongaloo to me was finding the salt intrusions and managing them to bring back the freshwater wetland.”

At Morratt’s Pit in Ayr a forest of green tree guards showed the huge amount of work being done to restore the area. Lower Burdekin Landcare Association has planted more than 2,500 trees there in the first half of 2017.

The day ended with a sausage sizzle. Vegetarian sausages always look like they might taste OK but actually taste like dirt with sage added. Next time I’ll go with the birds and try water chestnuts.

National​ ​Bird​ ​Week​ ​in​ ​the​ ​Bush​ ​Garden

We celebrated National Bird Week (23 – 29 October 2017) with a bird watching visit to the Bush Garden, led by our wonderful guide Michael McMaster from Birdlife Townsville. We had a fantastic turnout with 17 volunteers attended, including Cub Scouts and their parents from Pimlico-Mundingburra, Loam Island and Bluewater Scout troops.

The Bush Garden made for the perfect location to wander through the bush in peace and quiet, listening for any signs of the birds we sought. We had an exciting find from Sue who brought along what we identified to be a honeyeater nest, discarded after the chicks had hatched. The strength in the design and construction of the nest was incredible and it was great to show to the kids.

We discussed the recent installation of an owl box by Birdlife Townsville, which is now actually housing possums. These boxes are designed to provide habitat for large, hollow dwelling birds and have been constructed and installed because of the distinct lack of old trees with good sized hollows in our urban environment.

Jacanas provided a great talking point with kids eagerly watching through binoculars and trying to decide just how a bird could walk on lilypads, consensus seemed to be that their very long toes had something to do with it.

Our walk led us to the end of the Bush Garden at Aplin’s Weir where we came across, what some of us thought, the highlight of the day…a family of Tawny frogmouths! Two adults and two juveniles, of different ages, perched together on a branch. We also found the nest around 10 metres away in a beautiful paperbark overhanging the river.

Thank you to Michael McMaster, Birdlife Townsville and all the volunteers that turned up for a bit of birding and to celebrate our wonderful wildlife. We hope you had an enjoyable morning and that we’ll see you in the bush again sometime soon.