SWEET ACACIA AKA ​MIMOSA

​Lately I have been working the roadsides along the Newell Highway south of Moree, New South Wales Australia.
As such, I have had the privilege of seeing first hand the large variety of plant life that grows along the limited corridor of space between the edge of the road and the property boundary fence lines. In most situations the corridor alongside the highway can be up to fifty metres in width, some times more and stretches either side of the road. This generous amount of space provides growing room for a large variety of plants while simultaneously protecting them from the farmers plows on the opposite side of the fence. As such these corridors of growing space have provided ideal growing conditions for many species of plants. Looking at it from hindsight I have come to realise that these corridors are similar in construction to the ridge and furrow technique used in agriculture. Having said that whenever it rains onto these structures the water runs off the road and into the furrow (drain) allowing anything living in there an opportunity to thrive. As such, it is in these furrows that you can find the thriving life forms I have come to call corridor plants.
I classify corridor plants in the following way. A corridor plant must grow on the side of the road, they may or may not be considered a pest and they must thrive. It is this unwavering ability to thrive that made me interested in them in the first place. What piqued my interests most about them was the fact that these plants grew unintentionally without the use of fertilisers, frequent watering or any care from humans at all. They were a perfect example of life adapting to circumstance. As a result, a thought came to mind and that was that these plants could have potential uses in sustainable living practices that could be harboured to the betterment and value of all mankind.
I have previously written about one of these useful and edible “corridor” plants. This spinach looking plant is commonly known as Sorrel. Sorrel can be eaten directly from the plant, blanched under hot water or juiced to be used as a rennet for making cheese. So many uses from one plant. This lead me to think, if one single species of corridor plant could have such a variety of uses than what uses could other corridor plants have? As such I have kept my eyes wide open for all plant life on the roadside. I am frequently taking photographs for aids in later research. These photographs have helped me greatly and I have included a few to help you with identifying the plants I am writing about (see the photos at the start of the article).
During a morning tea break I come across another corridor plant of interest. The plant was lime green and about head high. It was shrubby with small spines and small yellow button flowers. Many thumb nail to thumb sized brown seed pods containing hard black seeds could be seen hanging from the branches (see the photo below).

It was not the first time I have encountered this plant, in fact I have seen this plant growing along side the road for years but could never find the time to do research into it. That has now changed.
Information regarding this plant was difficult to track down, especially when all I had was a visual description to work with.
Originally I was searching in government funded weed index’s, this was my first problem. The plant itself is not a weed in Australia, It is however considered an introduced species that has naturalised over the millennia (couldn’t it be argued that all plant species fall into this category?)
The plant is called Mimosa or as it is also commonly known the Sweet Acacia. The scientific name is Vachellia farnesiana. It is a legume from the same family of plants that yields beans and snow peas and like most legumes it is edible.
It has been recorded that the green seed pods were eaten by Australian aboriginals for thousands of years. Alternatively, the matured black seeds could be collected from the seed pods and milled into flour that was eaten in powder form.
The Mimosa (sweet acacia) legume is considered to be one of the most nutritious legumes on the planet.
The seeds when crushed into a flour contain 23% protein, 53% carbohydrates and 12% fat. The seeds are known to have a digestibility rating of 73% and 82% when cooked.
The flowers are used to make perfume, the bark for tanning and a purgative, the seeds can be pressed for oil (one of the main uses of the plant) and the leaves can be infused with water to make an insecticide.
Mimosa’s original land of origin has been linked back to Central America and southern North America. This would indicate that it travelled across the Bearing Straight before the land bridge was consumed by the ocean. After crossing the land bridge the plant travelled through south east Asia and finally into Australia. It is widely accepted that this movement was by natural means (most likely birds) and was not human assisted (as this would indicate early cultivation, a process not known to be practiced by the Australian Aboriginals).
To this day It is considered an invasive species in Australia even though evidence clearly states that the plant was here before Europeans arrived. It’s interesting to note that this plants ability to not only survive but thrive in Australia is the very reason it has been classified as an invasive species. Perhaps it is time we look see Mimosa from a different perspective, after all should a plant with so many uses ever be classified as truly invasive. I find it interesting that the rules of classification are bent to will of the agricultural industry of Australia purely to suit the interests of handful of saline soil cotton farmers. You see, classifying this plant as an invasive species has allowed farmers a loophole in which they can eradicate this species from the land without any fear of prosecution, this is an example of capitalism at its most craptastic.
I hope I have convinced you of the myriad uses of the Sweet Acacia. Clearly this is a plant that should be looked at with a fresh perspective, especially if sustainability means anything to you. Next time you see it on the side of the road consider stopping to have a look, I am sure you will come to understand my fascination with it too.