Youth Intern Program Aids in Conservation of Rare Fire-Dependent Wildflower

Tall larkspur in bloom.
Tall larkspur in bloom.

Tall larkspur (Delphinium exaltatum) is a nationally rare, fire-dependent wildflower with beautiful, purplish-blue blossoms that are highly attractive to butterflies and hummingbirds. This unusual species occurs primarily in the Appalachian corridor. The range of the tall larkspur is fragmented and populations that grow in the Missouri Ozarks are more than 400 miles west of the nearest Appalachian population. Because of the separation of the Ozark populations from those of Appalachia, there is great interest in learning more about the ecology of tall larkspur in the Ozarks.

In 2008, local botanists initiated a project to learn more about historical tall larkspur populations on NPS, state, and adjacent private land in the Ozarks. Some populations were discovered to be larger than previously known, and some had declined significantly. Several undocumented populations were also discovered. Most importantly, botanists recognized that tall larkspur in the Ozarks was strongly associated with fire-dependent open woodlands dominated by chinkapin oak.

This discovery prompted the investigation of the species’s reaction to prescribed fire, a project that was undertaken by the Missouri Area Park Group Fire Management staff at Ozark National Scenic Riverways (OZAR). OZAR’s studies of tall larkspur focused on fire ecology and restoration, particularly for populations growing within prescribed fire units managed by the NPS. Soon after the start of the project, botanists discovered a new tall larkspur colony at OZAR, which is now the largest population under prescribed fire management anywhere, with 3,522 plants.

Using funds available through the 2011 Youth Intern Program, botany intern Abby Hyduke was hired to expand and oversee the tall larkspur study. Analysis of the 2011 post-burn data suggested that tall larkspur was benefiting from prescribed fire. Plant counts from 2011 also indicated that almost 80 percent of the entire Ozark population of tall larkspur occurs within the designated boundary of OZAR.

Map of southeastern United States showing tall larkspur’s range.
Tall larkspur range distribution map.

While in the field conducting comprehensive surveys at sites with favorable tall larkspur habitat, Hyduke discovered additional tall larkspur colonies on private land adjacent to two existing prescribed fire units. The private land is managed by the L-A-D Foundation, a Missouri private operating foundation dedicated to sustainable forest management. With the cooperation of the L-A-D Foundation, Hyduke established permanent research plots and conducted inventories of the populations. These populations were burned in March 2012 through a partnership with L-A-D Foundation.

Youth Intern Program funding was used in 2012 to continue tall larkspur research. Christine Steinwand was hired for the position, but she sustained a severe knee injury that required surgery and rehabilitation and would limit her mobility in the field, turning her research to a new direction.

Botanists had wondered for many years if tall larkspur in the Ozarks had evolved into a distinct species. Steinwand was able to dedicate much of her time to a genetic study of tall larkspur across its geographic range. With assistance from the molecular genetics lab of the Missouri Botanical Garden in St. Louis, Steinwand developed genetic collection kits, which included essential materials and instructions, and distributed them to the appropriate botanists throughout Missouri and the seven eastern states within the range of tall larkspur. Collected specimens are currently being processed.

Steinwand worked diligently to raise the $1,500 needed to pay for the lab supplies used in the genetic analysis. State and private grants have been pledged to complete the analysis of the Missouri specimens. She also wrote a grant request to fund the collections from eastern states. Through these efforts, it appears that botanists will soon know whether the Ozark populations of tall larkspur are distinct enough to be designated a separate species. If that happens, this will be the only species of plant known to grow solely in the state of Missouri, and it will have significant implications for how managers approach the conservation of both the eastern and Ozark populations of tall larkspur.

Comparing monitoring data from the two prescribed fire units that were burned in March 2012, Steinwand found that the plot inventories showed that the number of plants in burned tall larkspur populations increased by an average of 9 percent from 2011 to 2012, despite record-breaking drought and heat. Monitoring data from an unburned “control” population nearby showed a 64 percent decrease in tall larkspur.

Youth Intern Program funding has been vital to the success of the tall larkspur project because none of the field work or associated research would have been possible without the botany interns. Thanks to the hard work and dedication of the Youth Intern Program botanists, the conservation of tall larkspur, and other rare plant species, may be made just a little easier.

Contact: Dan Drees, fire ecologist
Email: e-mail us
Phone: (573) 323-8027

Last updated: January 27, 2017