North Black Reroute Habitat Assessment for Cardamine pratensis

Transcription

1 North Black Reroute Habitat Assessment for Cardamine pratensis North Black River Reroute Description The North Black River reroute was identified by Minnesota Power and Department of Natural Resources (DNR) staff during a September 8, 2016 field review of the reroute area. The reroute begins at Structure B367 and angles southeast for approximately 3,900 feet to Structure B370. From Structure B370, the reroute follows County Road 86 south for approximately 6.2 miles to Structure B390 where it rejoins the Public Utility Commission s (PUC) approved alignment. The reroute was not surveyed for the presence of DNR Threatened and Endangered Species. This habitat assessment is provided at the request of the DNR to assess the potential habitat for Cardamine pratensis which is known to occur within adjacent areas of similar habitat types. Native Plant Communities of the Reroute Area HDR classified native plant communities using both the Minnesota Landcover Classification System as well as the Native Plant Communities of Minnesota key. The reroute was not surveyed on the ground, but field surveys were conducted along the adjacent, PUC approved right-of-way and native plant communities noted and recorded as Minnesota Land Cover Classification System (MLCCS) features. Using familiarity with the adjacent features combined with high resolution true color and infrared aerial photography, flyover video, Minnesota DNR Forest Inventory GIS data and topographic data (LIDAR), landcover and plant community types were ascribed to features on the reroute (See Figures 1 (1-7) and 2 (1-7)). In general, the reroute crosses a peatland basin dominated by coniferous forests at the northern and southern portions with stunted tamarack and black spruce bog and poor fen present in the central portion. Surficial geology of the reroute is comprised of Koochiching Lobe till plain adjacent to B367 at the northern edge of the reroute (Baudette Lake Plain Ecological Subsection), and along the southern mile (B382-B385) (Rapid River Till Plain Ecological Subsection). The central and dominant landform of the reroute is comprised of organic peat basin (Beltrami-Pine Island Peatlands Ecological Subsection). Forests in the northern portion of the Reroute are dominated mostly by () and Northern Rich Spruce () between structures B367 and B370. These areas appear to be high density, relatively young forests, managed for timber. Between B370 and B375, (), Northern Cedar () and Northern Rich Spruce () extend East/Northeast in directional bands parallel to the edge of the larger peatland basin. Immediately south of structure B372, there is a small area of wet aspen forest surrounded by a band of cedar swamp (). The reroute crosses open and stunted conifer plant communities between B375 and B380 and aerial photography would suggest that tamarack and black spruce dominated forests occur along this portion of the reroute due to road and ditch construction where the drawdown caused by the ditch has favored the growth of tree species. pen communities are also present within the reroute to the west, away from the effects of the road ditch. Forested areas south of B380 tend to contain a mix of more mature tamarack, cedar and black spruce. None of these forests are designated as old growth and all appear to have been managed for timber in the past. Mature cedar swamps are located on DNR lands at Structure B383 and on private lands at B384. Areas near these stands have been logged. Page 1 ctober 31, 2016

2 North Black Reroute Habitat Assessment for Cardamine pratensis South of B383, logged conifer forest has given way to a mix of wet aspen, white cedar, alder swamp and open, emergent wetlands. Typical Habitat for Cardamine pratensis Voss (1985) describes the habitat of Cardamine pratensis as wet bogs and marshy ground, borders of woodland pools and creeks, tamarack and cedar swamps. thers describe the habitat of Cardamine pratensis var. pratensis as a species of wet, cold bogs and limy swamps (Robert W. Freckmann Herbarium 2014). Cuckoo flower ranges from Minnesota east to the Atlantic cean and as far south as Virginia and in Northern Canadian Provinces from Newfoundland west to Alaska (USDA, 2014). The Minnesota Biological Survey (MBS) has found six populations of this plant since The MBS status update describes this species marsh, bog, swamp, and streamside habitats as a habitat that appears to be not particularly unusual or limited in northern Minnesota. Natural Heritage Information System (NHIS) records indicate that Minnesota populations are found in both open and forested wetlands with sufficiently mineral rich groundwater to maintain circumneutral ph (>5.5) (based on habitat types described and Native Plant Communities of Minnesota descriptions). Communities identified in NHIS data points include open rich fens, cedar swamps and river/pond/lake edges. In all locations, the species appears to inhabit basin and water body edges, or rich forest/opening community types. Canopy cover does not appear to either enhance, or diminish habitat potential, whereas all populations inhabit community types supported by inputs of neutral to mineral rich ground water. Margins of large peatland settings like those of the Reroute are typical. Habitat Present in the Reroute Cardamine pratensis is adaptable to both open rich wetlands and closed canopy settings. It is typically found in peatlands or mucky water basin edges. The species appears to favor locations where mineral rich groundwater is found immediately below the ground surface. The 2016 GNTL biological surveys identified a population within a cedar swamp immediately west of the reroute between structures B360 and B361. This area is described as a rich forest of cedar and black ash in a banded pattern paralleling the northern boundary of a large peatland. This cedar swamp community extends east to the reroute. GNTL biological surveys conducted in 2016 also identified a population of Cardamine pratensis in Itasca County. The Itasca County population is located in an area affected by changes to water levels from beaver activity (dams) years prior to survey. The population at that location was thriving and in full flower. Along the reroute, Cardamine pratensis has the potential to inhabit multiple community types where mineral rich groundwater is available. Rich conifer forests of tamarack and black spruce, but especially white cedar dominated communities are potential habitat. penings within these forest types and open rich fen communities may provide habitat as well. Additionally, NHIS records suggest that the species is not limited to pristine habitats but may persist in disturbed locations, including areas where the canopy is both closed and open. Based on these descriptions, habitat for Cardamine pratensis is available throughout the reroute in any of the rich conifer swamps, including forests dominated by cedar, tamarack and black spruce. The species appears to show the greatest affinity for cedar swamps within forested settings and is typically found at the interface between this and other plant community types. As such, habitats that could harbor this species are available between Structures B367 to B375 and B379 to just south of B384. Page 2 ctober 31, 2016

3 North Black Reroute Habitat Assessment for Cardamine pratensis Risk to this species from construction within the Reroute would most likely occur if the plant is found within the construction footprint near a structure location. Compaction or alteration of soils or direct destruction of habitat through rutting and careless operation of machinery could cause a take of Cardamine pratensis. Change in habitats from rich forested conifer communities to rich open communities would not likely cause a take to this species which is adapted to a variety of habitat types. As planned, there are no expected alterations to groundwater or surface water conditions due to project activities. Protection, Avoidance and Mitigation Site level surveys for Threatened and Endangered species were not conducted for the Reroute. Habitat for Cardamine pratensis is likely present in most of the wetland areas along the Reroute corridor, and especially in forested areas dominated by white cedar. In order to reduce the risk of a take of this species, the project proposes to minimize potential impacts by ensuring that construction is conducted with the least environmental impact. The Project proposes to minimize the potential for a take of Cardamine pratensis between Structures B367 to B375 and B379 to just south of B384 by implementing the following construction procedures: Tree clearing will occur under frozen ground conditions. Ground must be sufficiently frozen to allow for tree clearing activities to cause minimal damage or alteration of soils and existing above ground plants, consistent with the Vegetation Management Plan, Access and other construction activities will use construction mats, ice roads or low ground pressure equipment to protect against soil compaction, rutting and disturbance of existing ground vegetation, consistent with the Vegetation Management Plan, Construction mats will be removed at the earliest practicable time, If there is a sufficient time span between tree clearing and structure setting, summer 2017 surveys would be conducted to identify existing populations of Cardamine pratensis, If populations are found, a protection/mitigation plan would be developed in consultation with the DNR, and Protection against the movement of weed seed and vegetative material will be strictly monitored and adhered to. Page 3 ctober 31, 2016

4 North Black Reroute Habitat Assessment for Cardamine pratensis References Minnesota DNR Field Guide to Native Plant Communities of Minnesota: The Laurentian Mixed Forest Province. Ecological Land Classification Program, Minnesota County Biological Survey, and Natural Heritage and Nongame Research Program. DNR, St. Paul, MN. Minnesota Department of Natural Resources, Central Region Minnesota Landcover Classification System, Version 5.4. Minnesota Department of Natural Resources, St. Paul, MN. Minnesota DNR Species Profile: DNR, rare species information search page. Available at: Minnesota Natural Heritage Program Element occurrence records for Cardamine pratensis. United States Department of Agriculture PLANTS Database. Last accessed ctober 21, University of Wisconsin, Stevens Point Robert W. Freckmann Herbarium. Accessed: 2/17/2014. Voss, E.G Michigan Flora, Part II. Cranbrook Institute of Science Bulletin 59. University of Michigan Herbarium, Ann Arbor, MI. Page 4 ctober 31, 2016

5 Structure B366 B367 B368 () FPn73: Northern Alder () : (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 1 F 7

6 Structure B366 B367 B368 () FPn73: Northern Alder () : (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 1 F 7

7 Structure B369 B370 WMn82b WMn82a () () WMn82a B371 () FPn73: Northern Alder () : (): : White Cedar : Northern Rich Spruce : (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 2 F 7

8 Structure B369 B370 WMn82b WMn82a () () WMn82a B371 () FPn73: Northern Alder () : (): : White Cedar : Northern Rich Spruce : (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 2 F 7

9 Structure () B372 WFn64a () B373 () FPn73: Northern Alder () : B374 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 3 F 7

10 Structure () B372 WFn64a () B373 () FPn73: Northern Alder () : B374 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 3 F 7

11 Structure B375 Pn91 B376 () FPn73: Northern Alder () : Pn91 B377 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 4 F 7

12 Structure B375 Pn91 B376 () FPn73: Northern Alder () : Pn91 B377 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 4 F 7

13 Structure B378 Pn91 B379 () FPn73: Northern Alder () : B380 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 5 F 7

14 Structure B378 Pn91 B379 () FPn73: Northern Alder () : B380 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 5 F 7

15 Structure B381 WMn82 WMn82WMn82 B382 B383 () FPn73: Northern Alder () : (): : White Cedar : Northern Rich Spruce : (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 6 F 7

16 Structure B381 WMn82 WMn82WMn82 B382 B383 () FPn73: Northern Alder () : (): : White Cedar : Northern Rich Spruce : (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 6 F 7

17 Structure MHn46a B384 FPn73 () B385 () FPn73: Northern Alder () : B386 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 2 - PAGE 7 F 7

18 Structure MHn46a B384 FPn73 () B385 () FPn73: Northern Alder () : B386 (): : : : White Cedar Northern Rich Spruce (Black Ash-Conifer (CLIENT LG) FIGURE 1 - PAGE 7 F 7