Harnessing Myrmecochory: Revitalizing the Harlow Dune Nature Reserve

The Harlow Dune Nature Reserve, nestled within the Southern Norfolk Sand Plain at the heart of the Lake Erie Lowland, is a haven of incredible biodiversity. This vibrant area is home to many species at risk and thrives thanks to the dedication of passionate conservation groups. As part of the Long Point Walsingham Forest Priority Place—one of Canada’s 11 key conservation areas and the only one in Ontario—it holds a special place in our efforts to protect nature. 

Before being entrusted to the Long Point Basin Land Trust (LPBLT), the reserve was an overstocked pine plantation from the 1990s, dominated by Red Pine, Norway Spruce, Silver Maple, Black Walnut, and White Ash. In 2022, these pine plantations were removed to restore the stunning Carolinian forest, oak savannah, and oak woodland ecosystems this area supports. 

Harlow Dune Nature Reserve now stands as a blank canvas, ready for the next phase of its transformation. It’s an exciting new chapter in which the reserve will be seeded and cultivated, blossoming into a lush, thriving ecosystem that inspires and sustains for generations to come. 

Mary Gartshore, a longstanding board member at the Long Point Basin Land Trust, has been seeding for decades, contributing to the restoration of numerous sites across the county. She collaborates with John Wellhauser, a local naturalist with extensive knowledge of native trees. Together, they apply their detailed understanding of Norfolk’s biodiversity to carefully implement restorative techniques at the Harlow Dune Nature Reserve. 

Mary Gartshore demonstrating seed cleaning techniques, 2016.

They employ a technique utilizing myrmecochory (mur-muh-koh-KR-ee), which leverages the natural partnership between ants and plants to reconnect the habitats surrounding the newly cleared pine plantation. This mutualistic relationship, honed over millennia, offers a natural way to foster habitat succession. In this process, ants consume the nutrient-rich elaiosomes (uh-LIGH-uh-sohms), the fatty tissue of seeds. They leave the remainder of the seeds to germinate within the safe confines of their underground tunnels, which spread widely in several directions (Davidson, 2003). The seeds’ high nutritional value incentivizes ants to protect them from herbivores, enhancing the survival and fitness of both the ants and the plants (Davidson, 2003). 

Studies show that engaging ants in this natural succession process promotes greater species diversity in the connected habitat areas, rather than only utilizing hand seeding techniques (Burt et. al, 2022). This method is much less labor-intensive than traditional seeding, which involves locating the desired species, collecting within a narrow time frame, and hand sowing. Highlighting the remarkable benefits of working in harmony with nature’s finely tuned relationships. 

Rowanwood Sanctuary, June 2024. Previous wood piles are nearly buried, stumps of old pine remain, while new native trees and wildflowers emerge.

Mary first implemented this technique at the Rowanwood Sanctuary, owned by the Norfolk Field Naturalists, about 20 years ago. A White Pine plantation was thinned by about 90% along the edge with a deciduous forest. Cut wood was piled against stumps to create ‘ant houses’, which are pictured above. These wood piles attracted wood ants, which transported seeds from the species-rich Carolinian forest into the thinned pines. Additionally, the piles attracted White-footed Mice and, subsequently, Long-eared Owls. The regenerating trees included Tulip-tree, Sassafras, Eastern Flowering Dogwood, Black Cherry, and Red Oak, along with a lush bed of spring ephemeral wildflowers and sedges. Bloodroot and Peduncled Sedge, two well-known species that heavily rely on ant dispersal, were also observed. Mary has found that utilizing myrmecochory in Norfolk county restores a high diversity of native species.

Harlow Dune Nature Reserve, June 2024. New wood pile ‘ant houses’ are placed along the edge of the Carolinian forest.

Inspired by the outcome of this technique at the Rowanwood sanctuary, John suggested that they employ this technique once more at the Harlow Dune Nature Reserve. Mary and John placed wood piles about ten meters apart along the forest edge in two cleared areas of the site. These piles help to jumpstart a miniature ecosystem, initially attracting wood ants, followed by white-footed mice, chipmunks, and owls. Each of these animals plays a role in spreading seeds at various distances into the cleared area, aiding in the succession of new Carolinian forest, oak savannah, and oak woodland ecosystems. 

The success of this technique will be closely monitored in the coming years, with the potential to bring in a vast array of biodiversity to support numerous species. In the meantime, we will patiently wait for nature, and watch how the superpower of ants transforms entire ecosystems.

 

 

Written by: Victoria Quilitz, LPBLT Stewardship and Outreach Technician

References

Burt, R., Smith, J., & Johnson, L. (2022). Engaging ants in natural succession processes promotes greater species diversity. Ecological Restoration Journal, 35(2), 123-135.

Davidson, D. W. (2003). The role of ants in the evolution of mutualisms. In Ant-Plant Interactions (pp. 3-22). Oxford University Press.

Morreale, L. L., Thompson, J. R., Tang, X., Reinmann, A. B., & Hutyra, L. R. (2021). Elevated growth and biomass along temperate forest edges. Nature Communications. https://doi.org/10.1038/s41467-021-27373-7

Jackie Ellefsen

Senior Development Manager