FOVB Approves Site Habitat Restoration Expenditure at Volo Bog SNA
At its January 25, 2018 meeting, the Friends of Volo Bog Board approved an expenditure up to $12,000 for a major site habitat restoration project at the Volo Bog State Natural Area. This expenditure will be matched with a comparable State Wildlife Incentive grant. The State grant program is designed “to preserve, protect, perpetuate and enhance non-game wildlife and native plant resources of this state through preservation of a satisfactory environment and an ecological balance,” according to the Illinois Department of Natural Resources (IDNR) website. Together, the funds will provide the complete financing for this important Volo Bog SNA restoration project.
According to Brad Semel, who is the State Natural Heritage Biologist for the IDNR District that includes the Lake, McHenry, Boone and Winnebago Counties of Illinois, the purpose of this project is to “clean up for visual and ecologic reasons the area south of the Visitor Center to the Maintenance Building, then along Sullivan Lake Road as far as the available funds will allow” (refer to map). Years ago, this area along the bog in its more natural state of native grasses was visually open along the Tamarack View Trail so visitors could enjoy views of the bog. More recently, as reported by Mr. Semel, invasive species such as European or Common Buckthorn (Rhamnus cathartica) and Glossy Buckthorn (Frangula alnus) with their thick growth have gradually choked out the natural flora of native grasses and, therefore, also adversely impacted attracting natural fauna such as Blue-winged Teal (Spatula discors) and Yellow-headed Blackbird (Xanthocephalus xanthocephalus) that would normally inhabit this area. Also, the thick growth prevents underbrush development and growth and air movement to the upper woodland and permits more topsoil erosion and detrimental sediment to wash into the bog. In addition, the buckthorn has allelopathic chemical properties that inhibits the growth of salamanders and newts within the aquatic environment.
Restoration of the area will involve several steps consisting of: (1) initial clearing of brush, weeds and undesirable trees; (2) application of herbicide treatment; (3) maintenance (removal) of any exotics prior to seeding; (4) seeding of prairie grasses during next winter; (5) establishing a growth of prairie grass; (6) mowing the grass during the first season; and (7) periodic maintenance of the area using controlled fire burns.
Initial clearing will occur during winter by Eureka Tree Movers, an IDNR contractor, employing a “Geo-Boy SLGP 250. This equipment is a super-low ground pressure, 250-horsepower tractor with mounted high-speed Fecon brush cutter/mulcher head and riding on 30-inch wide rubber cross link tracks (refer to photo). This equipment imparts only 4.0 pounds per square inch pressure on the soil. It can clear unwanted trees and underbrush in a safer, more environmentally friendly way, protecting the soil structure and eliminating erosion and runoff pollution. Also, the feeder roots of desirable neighboring trees are not disturbed by the operations of this equipment, saving them from damage. The mulch created is so fine that no burning, hauling, dumping or chipping is necessary. Clearing is planned while the soil is frozen to further protect its integrity and will follow the Tamarack View Trail that will be used as the firebreak. Tight areas and steep slopes that cannot be cleared with the Geo-Boy will be cleared with IDNR’s Bobcat.
After clearing, herbicide treatment will be applied to disturbed areas by IDNR staff or its contractors to prevent further germination of invasive species. The herbicide is a type that is approved by the Illinois EPA for use in wetland areas.
During the summer, any exotics that grow will be removed by the IDNR staff and volunteers. After maintenance of the exotics during the summer, the area will be seeded next winter. Seeding in winter helps to control the growth of undesirable weeds in sown prairie grass seed.
Once the next growing season commences, the prairie grass will grow and develop and IDNR staff will periodically mow the grass during this season to further control weeds and to selectively allow the prairie grass to thicken.
During the second and third growing seasons, IDNR staff will use control burns to further develop the prairie grass, which requires fire to help cause new seed germination. Control burns will be conducted using drip torches (fuel is a diesel/gasoline mixture that burns slowly and non-explosively) while riding on ATV’s equipped with water for further fire control as necessary. The IDNR already has established fire burn plans for this purpose.
After this three-year period, the prairie grass should be well-established and future maintenance will then be limited to infrequent control fire burns that will further enhance the prairie grass growth. The IDNR staff already has completed well-established restoration and performs the necessary fire maintenance in areas at Moraine Hills State Park, so they are well-versed in the requirements and effort needed for developing and maintaining prairie-restored areas.
Mr. Semel explained that by removing the invasive species and restoring the area to a diversity of native prairie grasses including forb (broadleaf) grasses, switchgrass (Panicum virgatum), prairie dropseed (Sporobolus heterolepis) and other native grasses, this will improve the ecological diversity and health and make this area conducive to its native flora and fauna. The native grasses can grow roots from 12-20 feet so will significantly stabilize the soil A-horizon (topsoil) erosion that is occurring, aerate the soil, and enable precipitation from the upper areas to soak into the soil and not into the bog, thereby helping to better control the natural biology within the bog. As the native grasses develop, native fauna will gradually return to the area. Butterflies will return to lay their eggs and larvae/pupae will develop. A diversity of other invertebrates will also return. Flowers such as asters and goldenrods will establish and provide a variety of color during the warm months. In addition to teals and blackbirds as mentioned above, Virginia Rails and Sora Rails will frequent the area. Sightlines of the bog along the Tamarack View Trail will be greatly improved for hikers, once again allowing them to sit quietly and contemplate the wonders of nature in Volo Bog SNA.
(Article by Andy Ftacek after interview with Brad Semel on 2/8/18)