The shrubby tree acacia saligna is considered the most invasive plant in Israel. A new exhibit shows that it, and other invasive species, can be viewed in a different light
Shira Makin. Aug 22, 2023
Israel has a bitter, violent, toxic enemy. I’m referring not to our current government, though this description fits it too, but to something that for a hundred years has been sowing devastation throughout the country, destroying roads and railway tracks, ravaging pipeline infrastructures and tarmacs, bullying the local wildlife and pushing out native species.
Despite being known in Hebrew (and in English, under a secondary name) as “acacia cyanophylla” (“shita khalhala” in Hebrew, or “bluish acacia”), it is the shrub-like tree that in the spring carpets the ground beneath it with gorgeous yellow blossoms (and a recurring answer on New York Times’ Spelling Bee).
This tree, which can be seen through the window as one drives along the coastal road or walks the banks of streams, was brought to Israel from Australia by the British in the 1920s for forestation purposes – and has since spiraled out of control. It has become a serious threat, squeezing out habitats from the northern border to the northern Negev desert in Israel’s south.
Its story is one example among many of how humanity, with its inexhaustible hubris, interfered with complex ecosystems without understanding the potential damage. Today it is considered the most dangerous and problematic invasive plant species in the country, so hated that it is the only tree anyone can cut down without a permit. But attempts to burn or cut it down have failed since it renews easily. In desperation, authorities have escalated the violence of their attempts to eradicate this menace (which costs them millions) by, for instance, drilling in the acacia’s trunk and injecting a pesticide. Meanwhile, nothing really works. The acacia has put down roots here and isn’t going anywhere.
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But perhaps a new approach is needed? In light of the failure of the management and control approach, perhaps a more holistic worldview would work better? And perhaps, rather than fight the acacia, it can be harnessed for our needs? This is the question raised by artists Amalia Shem Tov and Orr Dagan, who examine other, original solutions to the problem of the acacia saligna. Their proposal is on display at the exhibit “Shmura” (“Preserve”) to mark the reopening of Beit Harishonim (“The Founders’ House”), a beautiful structure built on a sandstone bluff by the Ottoman Turks in the late 19th century which was abandoned in recent years, in Emek Hefer.
Beit Harishonim stands beside a nature preserve under the same name, as well as the Yaari sanitarium. Together they stretch over some hundred dunums (25 acres) of red loam and sandstone soil. It is a magnificent piece of nature, which in the winter and spring blooms with scilla hyacinthoides, lilies, naked ladies, cyclamen and daffodils among other flowers. Shem Tov and Dagan explored this wild natural space and the unique ecosystem surrounding it, and marked the points of friction between its preservation and human construction and development.
First they invited experts, including Dr. Boaz Shacham from the national nature collections at Hebrew University and Prof. Amram Eshel, alongside local residents, to map all the invasive species in the area. In the exhibit (which runs until September 2) the map of these species, including Bermuda buttercup, eucalyptus camaldulensis, chinaberry, camphorweed, West Indian lantana, and Ricinus communis is on display. The mapping also shows the differences between the two natural areas surrounding the structure – that of the nature preserve, meticulously maintained, and that of the abandoned sanitarium, which nature has taken over in post-apocalyptic style.
“We had one of our most interesting conversations with Dr. Oded Cohen, an expert on invasive species,” says Shem Tov (full disclosure: Her mother is a Haaretz employee.) “The approach is that invasive species are not a ‘black or white’ situation, and it always depends on the specific ecosystem.
Therefore, the plant has to be looked at individually, and we cannot come to sweeping conclusions like ‘let’s get rid of all the chinaberry throughout the country because it’s a bad species.’ There are places where it causes damage and has to be stopped, and places where it’s ok.”
She and Dagan tried to apply this concept to the acacia saligna as well. For four months, they worked with experts from the materials development lab at the plant and environmental sciences department to examine all possible uses of the acacia saligna – from the roots through the trunk to the leaves and fruit.
The whole process, including experiments with textures and colors, is on display at the exhibit. They propose to shear the tree a moment before the fruits fall, thus reducing its spread potential. Then to dry and grind it, and mix it into various composites – from which they created tiles, cylinders, and natural paint, produced by a process of extracting the lignin from the ground tree mixtures.
The rationale is on one hand to dilute its spread, and on the other not to eliminate it completely, so as not to harm the natural environment in the long term,” says Shem Tov. “Due to the prevalence of the acacia saligna here, we asked if it could be used otherwise, because eradication is mission impossible and potentially unwise as well. It’s a repeat of the approach of managing and controlling nature, and we doubt that. We don’t know what will happen in 20 years, after all.
Maybe we’ll need it? Maybe it will have positive elements? With all the forecasts of drying and desertification, it may be vital in 20 years, because it’s full of protein. So our proposal is to conduct ourselves less stridently and not kill it, and instead consider, as much as possible, that there are long-term implications in this matter of intervention and control, and that ecosystems change and move, with and without invasive species.”
In contrast to the acacia saligna, Shem Tov and Dagan show in the exhibit a testament to another eco-disaster in the area, caused by human activity – the grievous harm caused to the coastal sandstone bluff range, which is a unique geological formation that also serves as a habitat for a variety of local flora and fauna.
“The sandstone has undergone human abuse throughout history,” Shem Tov says. “They quarried the sandstone ranges and produced building blocks, drywall, and decorative elements from it. This use of it as a local raw building material and the urbanization process accelerated its reduction almost to the point of disappearance from the local landscape, and today many plants and animals unique to the sandstone range are at risk of extinction.”
The exhibit shows remnants of these uses, collected from various places around the country. “When they used the sandstone they didn’t know that a few years later, 38 species at risk of extinction would vanish from the world forever,” said Dagan.
This tension between nature and urbanity is one Shem Tov explores in another work dealing with the wadis of Haifa, some of which are threatened by construction plans. The work, “Bakarat Shehika” (“Erosion Control), curated by Dan Handel, is currently on display through December at the Haifa Museum of Art. It consists of three columns, totems of sorts, each of which is made of geological textures unique to three separate wadis, textures the artist copied with silicon molds. “It’s an attempt to bring the wadi into the museum,” she said. “To mimic something natural and dynamic and wild within my capability.”