Yellow flowers with circular bases, called Nelumbo Lutea , a species of Lotus flower, could have taken over Lake Raleigh on Centennial Campus.
As a possible start of an infestation, a worry that the species would be invasive to the Lake Raleigh ecosystem arose.
Jon Stucky , a professor in the department of Plant Biology, described some common traits of the invasive species.
“Many of [the lotus] produce more seeds, and the length of time the seeds remain living can be signs of invasiveness. Also there is a wide distribution of seeds rather than having only localized distribution of seeds they disperse farther away”
One of the fears with the Nelumbo Lutea was that it would grow to outcompete or out-crowd its neighboring plant life to become a dominant species in the Lake.
“Rapid growth, meaning invasive species grow faster than non-invasive species.” Stucky said. “The general thinking is that when a species moves and is distributed, by whatever mechanism, it is thought that no longer does that species face those factors that were inhibiting its spread in its native area. In other words, it sort of escapes, apparently, some restrictive factors, and when it escapes to a new area, it could take advantage of those biological characteristics.”
This species is known to reproduce quickly, Joanne Burkholder , a researcher and professor in the CALS Center for Applied Aquatic Ecology, said.
“They can grow really fast. I don’t know about the growth rates for the Lutea , but I know for the Nucifera , a close relative of the Lutea , they can take over an acre in a summer season. They can grow really fast,” Burkholder said.
Burkholder explained that much of the previous pollution of storm drainage and sewer leaks in Lake Raleigh could explain the added sediments that the Nelumbo Lutea thrive on.
“Lake Raleigh was once part of the City of Raleigh’s water supply. It also had miserable problems from sewers that cracked and contaminated the lake. So there was lot of fecal bacteria coming in and partially treated water and debris from the storm water pipes entering the water.”
Due to the rich levels of nutrients found in Lake Raleigh, the water makes a prime location for the Lotus to reproduce and grow.
“It has plenty of light, unlike a lot of aquatic plants; it’s in this rich sediment that doesn’t have much oxygen but is loaded with nutrients, so they’re in this perfect environment” Burkholder said.
Burkholder did not believe, however, that the Nelumbo are that detrimental to the Lake to be considered invasive.
“It’s just a plant that’s growing in the wrong place and we don’t like it. It might be a real pretty plant but it could take over the system and that could be a problem. Otherwise, it’s fine. I wouldn’t call it an invasive species but it could be the status of a weed right now,” Burkholder said.
In fact there are some benefits to having the Nelumbo Lutea close to the nearby ecosystems.
“It’s good habitat for water-fowl, It’s good habitat to hide in for animals like muskrat and some of the animals that are around. So it has some benefits. In some countries they eat the rhizome (roots),” Burkholder said.
The growth of the Lotus could possibly help the nearby wildlife when it comes to finding homes and safe habitats.
If it really came down to having to eradicate the plants, Burkholder listed some possible options, but all with varying consequences if used.
”You can try mechanical biological, which wouldn’t really work because we don’t know anything that eats them, like grass carpel eat hydrilla , for instance; but if you cut off the rhizome of the lotus, the upright grows back very fast. The rhizome is buried, it is thick, it is tough; In one of my aquatic plant classes three guys tried to dig one up and they couldn’t do it.”
The difficulty of having to dig up each Lotus would be inefficient at this stage in their growth, and would also cost a lot of money. The other option to eradicating the species was the usage of chemicals.
“You would have to use chemicals and I’m really not in favor of doing that if it’s just a habitat species that’s a little too thick for aesthetic tastes. I think it’s a shame to use pesticides because there’s enough of that in the landscape already. There’s enough problems due to pesticides already.”
The Neuse River Basin System is already known to be polluted by herbicides, which can have adverse impacts on the environments in which they are used.
The options of getting rid of the Lotus may have to be confronted soon, but as they are right now, they’re only a visual disturbance. They have certain visual qualities that could add to the Lake aesthetically due to their yellow blossoms and floating leaves.
“This species is just looking for habitat. All the construction that was done around centennial campus and the golf course and all the nutrients running off – there are plenty of reasons why aquatic plants or wetland plants end up taking off in areas we make it so desirable for them. It’s not the plant’s fault, it was such a disturbed area and the Lake was not taken care of well.” Burkholder said.
