Missouri Invasive Plant Council (MoIP) - to identify and control invasive plants

Missouri Invasive Plant Case Study Sites

Invasive plants impact society. While there are many problems with invasive plants throughout Missouri, these four sites are examples that show a history of invasive control and hope for future eradication efforts:

Golden Prairie

Location: Southeast 90th Road near Golden City, Barton County, MO 64748
Size: 630 acres
Landowner: Missouri Prairie Foundation

Species of invasives managed for: sericea lespedeza, tall fescue

History of land and invasives management: MPF purchased the remnant prairie in 1970 and 1972. Two additional tracts of degraded prairie and a crop field (which has since been planted with native prairie species) were added later to help buffer the good prairie. Management has been ongoing for exotics, and prescribed burns since 1997 have helped keep invasive woody species under control.

Results of management: Exotic control is an ongoing continuous effort. These efforts have been successful in keeping the exotics at low and manageable levels.

Current invasives management: multiple herbicide (triclopyr) spot treatments during the growing season on sericea lespedeza. It does appear to be working (hard for me to tell in two seasons) Fall treatment of fescue with glyphosate after a hard frost. This method works best if you can conduct an early fall burn and spray the fescue regrowth.

Other information: Golden Prairie is a very significant site. The 320 acre core is a remnant of unplowed original prairie that has been designated a Missouri Natural Area and National Natural Landmark. The prairie has a high biodiversity with 320 native plant species, an average coefficient of conservatism of 4.1 and 35 conservative species that indicate very good floristic integrity. There is a good array of grassland birds and 44 known species of bees (of which many are pollen specialists on prairie wildflowers and for two of them this was only their 2nd record in the state). Two species of conservation concern, the Prairie Mole Cricket and Regal Fritillary, and a candidate for federal listing (the Arkansas Darter) occur here. An upcoming survey of amphibians and reptiles, and other projects, will yield additional information about on the prairie’s flora and fauna.


Pump Hollow Natural Area

Location: Pump Hollow Natural Area, T 26N, R 3E, Sections 30 & 31
Size: 940 acres
Landowner: USDA, US Forest Service, Mark Twain National Forest, Poplar Bluff District

Species of invasives managed forThere are a few very small populations of multiflora rose (Rosa multiflora) within the natural area.  The biggest threat that is attempting to be managed is Japanese stiltgrass (Microstegeum vimineum).

History of land and invasives management: The land was likely acquired by the USFS in 1939 when it was part of the original Clark National Forest.  In 1976, the Clark and Mark Twain National Forests were combined and the Clark was absorbed by the Mark Twain NF.  Pump Hollow was designated as a state natural area in February 2015.  Before designation, the forest service had a systematic botanical survey completed.  This survey was conducted by a private contractor and consisted of a spring and a fall visit in 2012.  During these visits, both invasive plants and rare/threatened species were mapped and identified. The area also had a more general survey in the late 1980’s and again in 2008.  It was not until the 2012 survey that invasive species had been found in the area.

Results of management: Unfortunately, J. stiltgrass is highly aggressive.  It surprised land managers by how quickly it spread in just 2-3 years.  In June of 2016 the forest was able to establish resources that could start working on removal.  Because of the areas sensitivity, the forest tried to avoid the use of herbicides or contractors.  Six AmeriCorps crew members were tasked with hand pulling, bagging, and removing 5 island populations of J. stiltgrass.  Frustratingly, the 5 mapped populations had now merged and become generally 1 much larger population.  The crew was able to fill and haul out over 30, 50 gallon trash bags from the area over multiple days of laborious work.

Current invasives management: After realizing the daunting task that was hand pulling this population, the forest determined that hand pulling alone would not eradicate J. stiltgrass.  Pulling and hauling debris is too labor intensive, it demands too many personnel, and it has to be done during a brutally harsh time of year for the plants to be mature enough to pull.

The forest is adapting to the hand pulling struggle and attempting to try herbicide application using a Sideswipe®Pro herbicide applicator or similar product.  This device wets the plants evenly and eliminates the fear of drift and overspray.  This is extremely important due to the potential water threat.  Herbicide type will be appropriately determined and mixed according to labels and cautions.

Other information: This natural area features acidic seeps (a rare wetland natural community type) and a high-quality Ozark headwater stream and its surrounding watershed of restorable pine-oak woodlands.  The area supports 10 plant species of conservation concern, most of them associated with the rare seeps.  The area supports at least 258 native plant species and fish and invertebrate species associated with good quality headwater streams.

Katy Trail Honeysuckle Area

Location: The Katy Trail State Park between Dutzow & McKittrick
Size: 27 miles x 50′ wide R.O.W.
Landowner: Missouri Department of Natural Resources, Missouri State Park System

Species of invasives managed for: Asian Bush Honeysuckle – Lonicera maackii

History of land and invasives management: The Katy Trail is perhaps the most successful ‘Rails to Trails’ project in the country.  It was originally home to the M-K-T (Missouri-Kansas-Texas) railroad. It is a 240 mile long park that is only 50′ wide.  Managing such an unusual shaped park is quite a physical challenge.  Keeping the Trail passable to cyclists & hikers alike is a daunting challenge.

The Katy Land Trust (KLT) operates in a manageable region between Hermann and the confluence of the Missouri River with the Mississippi. It covers counties on either side of the Missouri River, reaching beyond the floodplain into the Riverhills region.  The 27 miles section selected is in the heart of what is now referred to as the Missouri River Country, an agriculturally rich region that boasts beautiful hills & vistas, the German Heritage District and the Missouri Wine country, as well as a very popular section of the Katy Trail.

Dan Burkhardt/Founder of the KLT and Jay Doty/registered landscape architect & field restoration specialist for the Open Space Council first met at a honeysuckle hack event along the Katy Trail 4/18/15 in Augusta, MO. The Open Space Council was operating as a support to the Katy Trail State Park & KLT.

The event was rained on, and no one was allowed to do RoundUp applications (cut stump method) so most participants were encouraged to hike and pull garlic mustard instead.  Not to be thwarted from an opportunity to eradicate honeysuckle, Mike Smith/Washington teacher, Greg Poleski/Greenway Network and Jay Doty determined to make use of honeysuckle poppers & shovels to chop roots and remove the entire stumps of some fairly large honeysuckle shrubs, including a 17′ tall shrub that the State Park staff had dubbed the ‘Granddaddy of Honeysuckles’ just below the Augusta Winery, adjacent to the Augusta Katy Trailhead.

This made an impression on Dan, who had recently formed the StopHoneysuckle.org website and put up the Enemy of the State billboards along Missouri interstates.  The core message of StopHoneysuckle.org is that as much as it seems like it, honeysuckle is not omnipresent in Missouri.  It often exists in pockets and if “outlying” plants can be located and eliminated the spread of the plant can be controlled.   The Katy Trail corridor provided an ideal location to demonstrate this thesis.  The assertion is that we desperately need a model (or several) for combatting invasive plants, like stream teams combat trash in our rivers.

He reached out to Jay and through some initial meetings describing his vision for the project. Together they determined that the mapping required was not technical enough to require a GIS system, but could be easily created within Google Earth, using its built in mapping features.

Over the course of a 3-week period of late May to mid-June of 2015, Jay mapped 27 miles of the Katy Trail.  The process was a fairly detailed drive-through technique where a vehicle was run along one side of the trail.  With each spot identification of honeysuckle along that side of the trail, a GPS reading was taken and the general size of the clump was estimated. Each incident was then mapped into Google Earth to give a easily understood visual representation of the density of honeysuckle within the KTSP right-of-way.  It does not give an accurate representation of honeysuckle plant communities adjacent to the state park, though some areas were noted for future reference.

This mapping is important because coordination of honeysuckle removal efforts along the Katy Trail are logistically challenging. Volunteers must be transported along the trail to where the honeysuckle is. (Many areas are within walking distance of a town or Trailhead, but not all).  It was also noted that perceptions were of honeysuckle getting less prevalent the farther away from the Metropolitan area one wandered.  To a degree this held true, though honeysuckle never fully disappeared from the trailside plant community.

It is also evident that streams, roads, trails and Greenways provide good sunlight for emerging Asian Bush Honeysuckle and as such are/have become ‘vectors’ for the spread of honeysuckle around the state.

Results of management: Once the mapping was complete, removal events could more easily be planned, because the initial reconnaissance footwork was complete.  The first such event was hosting the MICDS High School football team, which used it as a team building exercise in preparation for their upcoming fall season.  That was followed by the Honeysuckle Hike accompanying the Annual Treloar Elevator Party.  Other smaller events were staged, each picking different sections of the trail, often matching numbers of participants to numbers of honeysuckle.

As we got down to fewer sections, Jay was able to go out a few days on solo efforts to clean up areas that had more sparse populations.  The gravelly base along the old railroad right-of-way made for ideal hacking conditions as larger plants could come right out of the ground.  Plants were not required to be physically removed from the site, but could be left in piles that would be shredded by State Park maintenance staff mowers, which cover those sections regularly.

Only the area between Marthasville & Dutzow still contain sizable populations of honeysuckle.  Despite the initial success and pretty low regrowth rates, it is understood that there are several large honeysuckle populations just off the Trail right-of-way, often cascading down off limestone bluffs above the trail that will provide future regrowth for years to come.  However, the hope is to lead by example and encourage other nearby landowners to follow suit, and manage the honeysuckle on their properties as well.

Current invasives management: KLT is not settling for removing honeysuckle just from the Katy Trail, but also mapping roadside honeysuckles along Hwy94 and HwyU (from Warrenton to Hwy 94).

Other groups will continue to come out during KLT-sponsored celebrations in the region.  2017 is the Bicentennial of Marthasville, MO.  KLT will be preparing a celebration between Peers & Marthasville which will take another chunk out of the honeysuckle between Marthasville & Dutzow.

Other information: No one group can make the difference in honeysuckle on a region-wide scale.  The hope is to continue to enlist more and more partners in the fight as people begin to understand better how it threatens their beautiful region!

Cuivre River State Park

Location: On MO Highway 47, three miles east of Troy, MO

Size: 6,393 acres

Landowner: Missouri Department of Natural Resources, Missouri State Parks


Species of exotic invasives managed for: Garlic mustard, bush honeysuckle and European buckthorn are the top priorities because of their extent and severity. Autumn olive, sericea lespedeza, crown vetch, sweet clover and reed canary grass are scattered, or in scattered natural habitats, and control efforts are prioritized based on where they occur. Some species like burning bush, winter creeper, Japanese honeysuckle are beginning to show up in scattered pockets and will need control efforts going forward.

Current invasive management: Garlic mustard is primarily spot sprayed with 2% glyphosate in the spring (mostly April). For bush honeysuckle prescribed burning in woodlands is used to prevent its establishment, and additionally pulling, foliar spraying with 2% glyphosate, and cutting/spraying stumps with 25-30% glyphosate. European buckthorn and autumn olive are primarily controlled by cutting/spraying stumps with 30% triclopyr. Sericea lespedeza and crown vetch are spot sprayed with 2% triclopyr. Sweet clovers (both yellow and white) are primarily pulled when they occur in prairies and glades and reed canary grass is sprayed in one prairie site and pulled in a small sinkhole pond.

Results of management:  Garlic mustard control has been reasonably successful, keeping it confined to under 600 acres within the park and very significantly reducing its density within this area. Bush honeysuckle is exploding in areas surrounding the park; however, the prescribed burns are largely successful keeping it out of large portions of the park and other control efforts have been successful in some other locations. European buckthorn is bad in more disturbed habitats, but seems slow to become established in better quality woodlands and the combination of cutting and spraying and prescribed burns seems to be successful in keeping it under control. Autumn olive is not as abundant or widespread at this time, and the cutting and spraying does take care of the individuals treated, but overall it seems to be rather difficult to control. Treating sericea lespedeza, crown vetch, reed canary grass and sweet clovers in the scattered pockets of natural habitats they have invaded has generally been successful. These exotics have been eliminated or reduced from some sites, and all have been at least kept at low levels. Constant vigilance is required though, to catch reinvasions at an early stage. It is also apparent that prescribed burn units in the park promote more healthy natural communities that are more resilient to exotic species invasion.

Significant biological resources of the park: Cuivre River State Park is one of Missouri’s largest state parks, and one of the most significant natural resources in the east central region of the state. The park contains several thousand acres of woodlands, with small remnant prairies and limestone glades, and karst topography that includes sinkhole ponds, springs and caves. Over 730 native plant species are known, as well as 180 birds, 44 amphibians and reptiles, and 86 butterflies included within the list of over 2500 known invertebrates. At least 27 species are species of conservation concern in Missouri and one is federally endangered. Three natural areas cover 1968 acres (31%) of the park, plus there are two state park wilderness areas (2777 acres) and special ecological management areas cover 3935 acres (62% of the park).

All these irreplaceable natural resources absolutely depend on a significant and ongoing program for invasive exotic species control. Without these efforts thousands of acres of high quality natural communities within the Greater St. Louis Metropolitan Region are at risk.