Nebraskaland

AUGUST-SEPTEMBER 2015 • NEBRASKAland 17 Lowering the Yellow Flag By Justin Haag Visitors to a popular Panhandle attraction are seeing fewer blooms of one particular pretty flower – and that's being considered a good thing. T o many settlers of European descent who moved to the High Plains from the eastern United States in the 19 th century, flowers were used to brighten the landscape and add a touch of "the old country" to a new homestead. When someone planted a small stand of yellow flag irises near a pond on James Cook's storied Agate Springs Ranch in Sioux County, it's doubtful the family ever could have imagined the scene a little more than a century later. Over years, the irises from the Cooks' ranch amazingly spread eastward eight miles down the Niobrara River, near its headwaters where it flows through grasslands in the manner of a small creek. Each spring, more irises bloomed than the last, making a spectacular show of yellow during their short blooming period and delighting many visitors to Agate Fossil Beds National Monument. With the Cooks' ranch just to the west of the tourist attraction's border, most of the irises would bloom on public property easily viewed from the road. The show has proven to be too much of a pretty thing, however. Research showed the plants were not only negatively affecting water quality, but were also changing the stream's flow. In many places, for instance, plants had grown in from the sides and caused the active channel to deepen and the water to flow faster. The characteristics of the river's flow are considered to be important along the upper Niobrara with rare minnow species such as the redbelly dace and finescale dace. Nick Sanderson, the Sioux County weed superintendent, worked with the Nebraska Game and Parks Commission to gain approval from the Department of Environmental Quality to have the irises sprayed with Habitat, a herbicide approved for aquatic applications. Sanderson said funding has been a huge hurdle for the project, but the Nebraska Weed Management Area Coalition has helped secure grants from the Nebraska Environmental Trust and a few other sources. The first contracted spraying was last fall, but iris can be a stubborn plant. "We put a huge dent in them, but it's a little discouraging to see how many survived. We knew we weren't going to get rid of all of them overnight," he said. "We're making headway, and you can see grass growing in places that were covered with iris last year." Of course, the High Plains of western Nebraska isn't the only place yellow flag iris, or Iris pseudocoris, has been considered a problem. A number of states have even prohibited the pretty plant. Irises are a popular variety for beginning gardeners, but people are advised to plant them in dry locations where there's no risk of its seeds and rhizomes moving along waterways and competing with other shoreline vegetation. With such hearty characteristics, yellow flag irises will be showing their color for centuries to come – hopefully just not along the Niobrara River of Sioux County. ■ PHOTO BY JUSTIN HAAG

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