An Oak Savanna is Born

Converting a dense closed canopy forest overrun with buckthorn and other nonnative brush into an oak savanna has proven to be a challenging endeavor. While the transformation is still a work in progress, it has reached a stage where referring to it as a savanna is not entirely implausible...or perhaps it should be called a budding savanna. You can witness the ongoing changes by trekking up Hickory Trail from the lower Hixon parking lot to Savanna Trail. On Savanna Trail, you will be greeted with this view (though significantly distorted in the panoramic photo) of the area:

If you're feeling ambitious, you can proceed up Savanna Trail, then turn left onto Vista Trail. Follow this trail to a spur trail that leads to the summit of Lookout Prairie. From there, you'll be treated to breathtaking views of the prairie, with the City of La Crosse and the Mississippi Valley in the distance:

A few years ago, the project began with the aim of creating a more natural transition from the prairie above to a savanna below, which was considered to have greater habitat value compared to a sudden shift from prairie to a dense forest. The image below, taken in June 2022, after work had already begun, shows this previous dense forest with a thick buckthorn understory:

The project has progressed successfully thanks to the collaborative work of contractors and many volunteers. Over the last few years many trees and brush have been removed and either hauled off the savanna or burned as seen in this photo taken on April 4, 2024:

The most recent effort came from a WisCorp Crew during the first week of June.

Standing at the back are Beth, Maddie, Will, and Grace. Kneeling in front are Mars, Noah, and Bella.

But, what exactly is a savanna? Here is one definition provided by the USDA:

"Although definitions vary, one common definition is: an oak savanna is a plant community with scattered “open-grown” fire tolerant oak trees. Other terms for these savannas are “oak openings” and “barrens”. In contrast to a forest, which has a closed canopy, the oak savanna canopy ranges from about 10% to 30%. In such a habitat, the ground layer receives sun and shade, which permits growth of a wide diversity of grasses and flowering plants. There is usually enough sun to the ground to permit the growth of typical prairie species, such as big and little bluestem grass, and many goldenrods and asters."

Today, less than 1% of the original native prairie remains, as reported by The Prairie Enthusiasts. Original oak savannas are even more scarce, with some estimates suggesting only 0.01% still exist. It's important to note that our savanna is not original, as any remnants from a previous era had disappeared entirely. However, by restoring the original or remnant prairie above, there is optimism that many of the more shade tolerant prairie plants will naturally spread into the savanna, a process that is already underway, or with our assistance in dispersing their seeds.

We have also dispersed seed on the savanna that was purchased from a local nursery. The plants from these seeds are considered to pose no threat of invasion or disruption to the prairie above, and include Virginia wild rye, slender wheatgrass, poverty oats, tall thistle, sweet Joe-Pye weed, and yellow pimpernel as recommended by experts at The Prairie Enthusiasts. Other desirable native plants have appeared naturally on the site, such as American figwort, poke milkweed, and common milkweed. One of the goals for these plants, particularly the grasses in combination with oak leaves, will be to supply sufficient fuel for a controlled burn this autumn or winter. Savannas, like prairies, depend on fire, and regular burning will be essential for the upkeep of this area. Notably, we have observed increasing animal activity as the area has been opened, including many more insects, particularly bumblebees on the figwort. Beth from the WisCorp Crew also discovered a monarch caterpillar on one of the common milkweed plants growing in the savanna:

And one year ago, we saw this unfortunate toad being consumed by a garter snake:

We believe that this new habitat will only increase in its value to many other plants and animals as it matures.

We would like to express our gratitude to all the volunteers who have played a part in this project, transforming a dense monoculture dominated by buckthorn into the lively savanna showcased in the photos above, with a special mention of the exceptional recent work done by the WisCorp Gang! However, there is still a significant amount of work to be done on this savanna and on other sites. If you are interested in joining our volunteer team, please reach out to us at friendsoftheblufflands@gmail.com.