Thirsty salt cedar trees are wreaking havoc with area water supplies, competing for precious resources.
But fortunately, there’s a solution — bugs.
Rather than eliminate the trees with chemicals, researchers introduced to their habitat a species of beetle that does the destruction for them. The salt cedar leaf beetles and their larvae eat the tree’s leaves, but don’t seem attracted to regular cedar trees — or hardly anything else, for that matter.
“The beetles will strictly eat the salt cedar,” said Glen Killough, district conservationist in Garza County. “They’re pretty amazing.”
The salt cedars, also known as tamarisks, are considered an invasive species. That means they’re not native to the areas they live now, but have pretty much taken them over. They have higher water demands than many of their indigenous peers, and are likely to be found where they can find lots of it.
“They are a big water consumer, and that’s where they grow — along rivers and lakes,” Killough said.
One of those water sources is Lake Alan Henry, which — like other municipal water suppliers — could have better uses for its limited resources. City and area officials have listed water as a top concern, and most have voiced support for projects that help conserve it.
“Many years of studies indicate salt cedar takes a lot more water than most vegetation,” said Aubrey Spear, Lubbock’s director of water resources and environmental management. “...The beetles will be good partners.”
The salt cedars don’t seem to be very good neighbors to fellow plants, either. While not only drinking more than their fair share, their roots also tend to alter the balance of the soil content.
“They change the soil pH and make the ground saltier, which inhibits natural plant growth,” said Greg Jones, agriculture agent for the Garza County branch of Texas AgriLife Extension Service.
A pH number reflects whether soil is acidic or alkaline.
The trees are native to Asia and the Middle East. How and when they landed in Texas is not completely certain, Jones said, but could have been related to landscaping aesthetics and erosion control.
Herbicide applications are a standard method for dealing with most unwanted vegetation, but they can have unintended effects on the surrounding environment. They’re also temporary — the sprayed-upon trees will return.
“When you spray chemicals on an area, anything that will kill salt cedar will also kill native plants you want to keep,” Jones said. “Biological control is the most logical control. It’s a lot more economical in the long run.”
After the beetle consumes the salt cedar leaves, the process of photosynthethis halts and the roots die.
Migrants themselves, the bugs are native to the islands of Crete and Tunisia. Researchers introduced them in Texas a few years ago, hoping they can grow as abundant as the trees they were put there to stop.
“We’re hoping to get them established so they’ll spread on their own, and they have in some areas,” Jones said.
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