Appendix F Detailed Cover Type Tables - USDA Rural Development

Bemidji – Grand Rapids
Biological Assessment and Evaluation
limited, but may reappear after clearing, possibly due to new shoots from dormant buds, or from seeds
known to remain viable for long periods.
4.2.5.16 Ram's‐Head Ladyslipper (Cypripedium arietinum)
Ram’s‐head ladyslipper is listed as DNR Threatened, CNF RFSS, and DRM Threatened.
Potential effects for this species are described in the following Guilds: Cedar and Mixed Conifer Swamps.
Species Description
Like all members of this genus, C. arietinum has 3 petals, 1 modified into a pouch or “slipper.” In C.
arietinum the pouch is densely pubescent and white with purple markings, which, with a little
imagination, looks like the head of a charging ram. It has 2 or more alternate leaves borne nearly to the
top of the stem. The lateral sepals are free rather than fused, which distinguishes C. arietinum from all
other Cypripediums (Smith, 1993).
Species Habitat
The Minnesota populations of C. arietinum occur in a variety of coniferous forest habitats. Several
populations occur in swamps, bogs, or lowland forests dominated by Thuja occidentalis (northern white
cedar), Larix laricina (tamarack), Abies balsamea (balsam fir), or Picea mariana (black spruce). The
species also occurs in the drier upland conifer forests that may be dominated by Pinus strobus (white
pine), P. resinosa (red pine), or P. banksiana. All these habitats appear to be weakly acidic or
circumneutral, but vary in their mineral composition from poor to rich (Coffin and Pfannmuller, 1988).
Forest, bogs, acidic; bedrock; shorelines‐interdunal areas; wide variety of forested habitats; (tends to
uplands on Superior NF; wetlands on CNF). This orchid occurs in shaded low dunes along the Great
Lakes, under jack pine‐oak forest, in coniferous swamps, and fir‐ cedar‐spruce bogs. Case (1987) notes
that it occurs on both sub‐acid and neutral soils. Associated species include white cedar, balsam fir,
spruce, pine, paper birch, Ledum groenlandicum, Linnaea borealis, Gaultheria hispidula, Arctostaphylos
uva‐ursi, Cypripedium acaule, Chimaphila umbellata, and Aster species (Case, 1987; Ostlie, 1990d).
Species Distribution and Occurrences within the Study Area
C. arietinum ranges from Ontario and the Canadian Atlantic
Provinces to Maine and New York, west to Northern Minnesota and
in a band extending through central Manitoba and Saskatchewan
(Brzeskiewicz, 2000).
USDA Plants Database at:
http://plants.usda.gov/java/county?state_name=Minnesota&statefi
ps=27&symbol=CYAR5
Cyprepidium arietinum is listed by the DNR, DRM and the CNF with
element occurrence data available by each agency. Point data
provided by these agencies identifies approximately 12 distinct
populations located throughout the Study Area (point data within the same basin is grouped).
Risk Factors
Principle recognized threats to this species include timber clearing, associated ground disturbance and
increased light with accompanying soil drying. The species appears to prefer mid‐successional forest
habitats formed from past disturbance, so full canopy closure may adversely affect the species as do
forest clearing practices. Other potential threats to this species include alteration of drainage patterns
July 2010 Species and Associated Habitat Page 4‐59