TREASURE COAST - Dr. Carey Minteer is a University of Florida Institute of Food and Agricultural Sciences entomologist leading a state plan to control 700,000 acres of invasive Brazilian peppertrees through the introduction of insects that feed on the tree in its native Brazil.
Dr. Minteer and her associates work at the UF Norman C. Hayslip Biological Control Research and Containment Laboratory in Fort Pierce, part of UF’s Institute of Food and Agricultural Sciences. The lab is a high-security facility where possible biological control insects are quarantined and tested against the state’s costly invasive species.
“We do biological control of invasive weeds, using natural enemies like insects, mites, sometimes fungus, to naturally reduce the impact of these invasive weeds,” Dr. Minteer told Hometown News.
“To do that, we go to the areas that these weeds are from, like Brazilian peppertree is from Brazil. We look for things that are feeding on these plant species. We narrow that down and bring some into a special lab we have here called a quarantine or containment lab, and we work for 10 or 15 years to make sure these things are going to be safe, they’re not going to feed on any other Florida plant species, they’re not going to bite people, they’re not going to spread disease, they’re not going to be toxic to cattle. We really want this to be safe.”
“Once the federal government approves us to release them into the environment, we put them out and this acts as a natural pest control. They feed on the plant, the plant has to defend itself using resources it would otherwise use to grow faster and produce a lot of berries. So it’s a very sustainable way of controlling invasive plants. There is zero chemical use. Once the insects are out there they make more insects and spread on their own, so we can move on to looking at other invasive plant species, so it’s extremely cost-effective and, in my opinion, the best way to control landscape-level invasive plant species.”
We asked Dr. Minteer if bringing in such insects could have negative, unforeseen consequences, and she said that their research makes that highly unlikely.
“We do a lot of research on these insects, and we are very highly regulated. There is a team of federal scientists, academic scientists, scientists from Canada and Mexico that review our work. We once were using a species of insect that was related to another insect that was toxic to wildlife, so that insect did not get released. We’ve been doing biological control in the United States since 1902, and there are very few instances of direct non-target impacts from the biological control of weeds. We’ve had very few instances of our insects feeding on other plant species, and most of the time those were predicted in the lab. There are zero instances of insect species we put out, for example, being fed upon by frogs, and then the frogs die, or the species that eat the frog die. We are also doing research to see if the food web in a given area changes due to the introduction of an insect. So far we have found no effect outside the direct plant-insect relationship.”
In 2019, Dr. Minteer led the statewide effort to distribute the first insect, the Brazilian pepper thrips, onto state parklands and private ranches. Dr. Minteer and her team aim to replace chemicals with insects tested to affect only the Brazilian peppertree, which costs one rancher a quarter of a million in chemicals annually.
“The money we spend to control these plant species is hard to quantify, but it’s definitely in the millions of dollars. For Brazilian peppertree in just conservation areas of Florida, they spend about $2.1 million annually controlling it. That’s just actual control costs in conservation areas in Florida, not including private land and not including a lot of the public lands. So it’s millions of dollars.”
One implication to the research could be a massive reduction in the use of chemicals, but Dr. Minteer was careful to note that she is not anti-chemical.
“I don’t want to demonize all chemicals. A lot of the chemicals are necessary and very specific, and very helpful. But the long term impacts of some of these things we don’t know. Remember DDT in the 50s and 60s. We thought the chemical was the be-all-end-all for insecticides. Later we found out about non-target impacts on birds and people. So any reduction in the amount of chemicals that we put out there is going to be beneficial, not just from an ecological standpoint, but from an economic standpoint. Chemicals are expensive, and paying people to put them out there is expensive. Reducing that is a benefit for both the environment and the economy.”
Dr. Minteer teaches all of this to children in a six-week program at Glendale Elementary School in Vero Beach and Samuel Gaines Academy in Fort Pierce.
“We teach these kids about invasive species, not just plants but also animals, so they understand how they get here, the damage they can cause, what we can do to prevent bringing those in. A lot of the invasives we have here are because we have brought them in on purpose. So if you educate kids at third grade, or at Samuel Gaines its sixth graders, hopefully that will start to change and people will make better choices, like planting native species, and not bringing back seeds from other countries because you thought the plant was pretty.”
If it sounds like a complicated topic for third and sixth grade students, Dr. Minteer says that the subject matter is taught at an elementary school level, molded by their teachers, and the children grasp it well.
“We do it over six weeks. It can be complicated but we speak to them at a third grade level, and we play games, where some kids play native plants and some kids play invasive plants, and they get to have this big habitat that they’re growing in, so they can actually see what happens. Then we introduce biocontrol agents and talk to them about how biocontrol agents only eat their target plant species. We do that in all sorts of activities where we can break it down into small chunks.”
“The kids have really responded well to this. We do pre- and post-tests, and their test scores are way up at the end. We have a quiz bowl where the classes or groups can play against each other and see who’s learned more.”
“And we work really closely with our teachers. I am not a third grade teacher, I’m not a sixth grade teacher. We rely on teachers to help us modify the programs so it will be more easily digested by these age groups.”
The program at the two schools has another important aspect unrelated to the specific subject matter. Dr. Minteer loves that she is exposing underrepresented groups to the idea that they can be scientists.
“The benefits of that are getting kids interested in science. My lab is extremely diverse. Many kids have never seen a female scientist or a Black scientist, so to be able to see Black scientists and women scientists and Latino scientists is eye-opening for some of these children. For them to see themselves in something like this helps. If just one kid in that class says ‘I didn’t realize I could be a scientist’ and then finds a love for science, I think that’s tremendous and I would consider that as evidence the program has been successful.”
“We’ve had comments from the young children, especially children from under represented groups, comments like ‘I didn’t know girls could be scientists.’ That breaks my heart, but now she knows that she can be a scientist.”
“We’re hoping this program can get some funding to take it Treasure Coast-wide. Right now we’re doing a lot in these two schools, but if we could to this Treasure Coast-wide that would be the most impactful to actually making change on the Treasure Coast.”