Mississippi River Wildlife Biologist for the Wisconsin Department of Natural Resources, Brenda Kelly, wanted to get to the ending first.
“We don’t know.” They have an idea possibilities of why there has been a bumper crop of wild rice in the waters surrounding Potosi along the Mississippi River, and they believe that some rumors are simply not true, but to have a definitive answer is not something that is known.
Could it have been washed in when the Mississippi River had very high water this past spring? It is possible.
Was it the result of an erosion prevention project being washed into the river? Most likely not.
“I am pretty comfortable saying no,” Kelly said last week in a telephone interview about one of the rumors on why there was so much wild rice. The rumor had been that the rice had been planted along a river bank to prevent erosion.
Kelly said she checked on every project that was taking place along tributaries that empty into the Mississippi River, and simply found no project that used rice.
The more plausible conclusion - conditions have been such that have allowed the native plant to make a resurgence back into the river.
Historically, wild rice has been up and down the Mississippi River. “We had a free-flowing river system before 1930s,” Kelly stated, and noted there are plenty of historic accounts that wild rice was plentiful in the river, including in this region.
For whatever reason, rice disappeared from sections of the river, at least visibly.
But in more recent years, the plant has made a resurgence in pools north of here. Kelly pointed to the U.S. Geological Survey, that stated that wild rice was detected at only 1-3 % of sites annually between 1998 and 2008 but expanded rapidly between the mid-2000s and 2019.
High detection despite sustained high water in the spring of 2018 and 2019 suggests that wild rice tolerates high water velocity and low light conditions in its early stages of germination and development. In 2020, prevalence decreased sharply to only 10% of sites however, wild rice has since rebounded and, in 2023, was detected at 37% of sites in Pool 8. Interestingly, prior to 20212023, the highest frequencies of wild rice were observed in the years of highest growing season discharge and water depth.
“We are seeing that increase across the pools,” Kelly continued, noting strong amounts of rice in upper pools in past years.
One possibility was that the high waters in the spring flushed through pools, like the one Potosi is in, and what it did was wash out preexisting plants, and allowed for rice to come in.
Then, with the low water of summer, it may have made conditions just right for the rice to grow rapidly.
So, is the rice a good thing or a bad thing? For Kelly, it is a good thing, providing food and cover for wildlife in the river refuge.
Unlike invasive plants like Flowering Rush, the rice is bringing “What we are talking about is a native plant that has a niche in the ecosystem,” Kelly said.
