Some Big Bluestem is tall enough to “tie across a horse’s back” due to plentiful rainfall this season at Lewis & Clark Recreation Area. One of the mature native grass stands can be seen up the hill to the east of the Gavins Point Road entrance near the disc golf trail. Shane Bertsch, district park supervisor and Dale Dawson, conservation foreman, discuss native grass, wildflower and tree projects this season at the state park. Jake Manning, park manager completing his first year at the park, takes in the discussion of projects begun earlier.
Park Entrance Wildflower Project
Three-acre pollinator demonstration plots displayed native grasses and wildflowers on either side of the Lewis & Clark Recreation Area entrance in 2015. The plots also encouraged a wide range of insects, part of a pheasant’s diet. Stewart Elementary 4th graders from Susan Goeden’s and Michele Fleer’s classes hand sowed wildflower seeds on the snow during the late winter of 2015 in one of the large native grass plots. Pheasants Forever volunteers were project partners. A Pheasants Forever member presented a program to the class about wildflowers and pollinators. Flowers bloomed, but by late July, Marestail, a persistent weed, had overtaken the plots.
After an herbicide treatment and then seeding, native grasses and wildflowers displayed again in 2016 and in 2017. Halfway through the season, noxious Marestail appeared in the plots and overtook the pollinator plots. Marestail has several cycles to produce seed in a season and is resistant to glyphosate. Finding effective treatments to keep native grasses and the desired array of wildflowers, while eradicating Marestail, is a challenge.
“I sprayed Milestone broadleaf herbicide in September, 2017. It’s a pre-and post-emergent chemical. Some of the wildflowers are tolerant to Milestone,” Dawson said. He says he is careful to stay within application restrictions. This is a product that can be used for habitat restoration.
“I hope we’ll get some of the wildflowers back,” he said. When Marestail is in the “rosette” stage of growth as a young vulnerable plant, he plans to apply another application of Milestone. “The bad thing is that the wildflowers may be in the young and vulnerable stage then too. But if I don’t do something aggressive, I’ll never get ahead of Marestail. My Dow Agro representative says I’m not the only one having trouble with this plant. We might have to sacrifice color to get the Marestail under control. Hopefully no more plants will emerge from Marestail seed.”
“We did a dormant wildflower/native grass re-seeding on Nov. 6, 2017,” he said, “using the Yankton Conservation District’s food plot seeder.” Native wildflowers included: Black-eyed Susan, Meriwether Blanket flower, Blue Flax, Lance-Leaf Coreopsis, Partridge Pea, Plains Coreopsis, Prairie and Purple Coneflower, Purple and White Prairie Clover, Smooth Blue Aster and Western Yarrow. Native grasses selected for the re-seeding included Bad River Blue Grama, Itasca Little Bluestem and Butte Side Oats Grama. They wanted native grasses that were short enough so that the wildflowers would display well. A lawn starter was included in the seeding.
“We had a cool, wet spring (in 2018). Chemicals didn’t seem to work. It rained and pre-emergent herbicides became ineffective,” Dawson said. Invasive Marestail grew again and choked out other plants in the plots by the end of July. “We had 70-80 percent coverage of the plot with Marestail.
Bertsch says the park might try to burn too next spring if we have enough vegetation. “We’ll always have native grasses in the plots.”
“Next spring we’ll apply Milestone pre- and post-emergent herbicide, and maybe again, and see what happens,” Dawson said. “Having the wildflowers with them is the most challenging thing to deal with. It limits what you can do.”
“With these plots, we didn’t wait the extra year to start growing wildflowers. We could have kept it bare ground or planted a cover crop. We wanted the plots (by the entrance) to look decent and turn out the best they could,” Bertsch said. An alternative two-year weed eradication plan is underway with a multi-use trail plot described below.
Other Native Plots
Though land for native grass and wildflower plots is limited at the park, a four-acre pollinator plot is in its second year of preparation before seeding. The plot is located at the west end of Gavins Point Road next to the multi-use trail. It’s going to be the park’s next pollinator plot and will have wildflowers as well as native grasses.
“I sprayed this plot in the fall of 2016 and the spring of 2017 to kill all the vegetation. To prepare the soil I sowed sod-buster turnips and radishes as a nutrient-building cover crop in July of 2018. Next spring we’ll burn it or mow it. Then we’ll sow the native grasses and wildflowers,” Dawson said. This two-year method was used to help eliminate weeds before sowing the wildflowers with native grasses in contrast to how the entrance pollinator plots were established.
Stands of established native grasses can be seen on the south side of Highway 52 near the rural fire station. Other mature native grass stands are up the hill to the east, past the entrance to Gavins Point Road, and by the parking lot at Gavins Point Nature Trail.
Selective Tree Removal
Taking down and replacing trees is part of the management plan at the park.
“Every year I take down about a hundred trees,” Dawson said. As for tree removal criteria, Dawson said, “It is the “three D’s” — dead, dying, or diseased. I look for lightning strikes or mower damage. If it’s an ash tree in decline I might take it since it will come out later,” he said.
“Some of the trees we have to remove were planted here in the 1960’s,” Bertsch said. “Initially, enough trees were removed to put camper pads in. We’ve thinned as trees have grown together. We often plant a new tree in the area we had to take one out.”
“Campers have grown larger so we’ve had to extend pads. We also have added some 50 amp upgrades for today’s larger camping units,” he said.
One of the uses of wood at the park is to replenish the firewood supply for the camper season.
“We had more of our firewood used this year because of change in regulations due to the presence of Emerald Ash Borer in Sioux Falls and two adjacent counties, and no firewood from out-of-state. We confiscated 240 bundles of firewood that people brought in from out-of-state or one of the quarantined areas in South Dakota,” Bertsch said.
“We’ve taken thirty or forty dead Austrian and Scotch pines off the Gavins Point Nature Trail that were killed by Pine Wilt Nematode. “It’s tedious because of the slope and hard to get to. We don’t use the pine for firewood. They are very dry and brittle,” Dawson said.
Austrian and Scotch pines with Pine Wilt are on the tops of hills along Gavins Point Road. They were planted there in the early 1960’s and are not native trees.
“I don’t want to take them down before their time,” he said. “We leave trees with green needles, and only take the dead ones. If all the trees were removed it would look like the hills were clear cut.”
Pine Wilt comes from native nematodes commonly found in the soil. Nematodes are carried from one infested exotic Scotch or Austrian pine tree to another by the Sawyer beetle. Tree death usually occurs within the same season. Individual trees may be injected. Lack of selective spray for Sawyer beetles makes spraying pines that are close together not feasible.
The native Ponderosa pine has more defenses against Pine Wilt, according to Dr. John Ball, SDSU Extension Forestry Specialist. Pine Wilt was found at Lake Andes in 1981, according to Ball. It appears to be moving north and he has seen it in Watertown and Spearfish, but it is commonly found in southeast South Dakota. Pine Wilt is prominent in Nebraska. The Backyard Farmer website at University of Nebraska-Lincoln has additional information on the disease. See: www.byf.unl.edu.
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