Cedar Creek Natural History Area

Plants of Cedar Creek

The Evening Primrose Family contains a variety of attractive herbaceous plants.  Flowers and stamens are 4-partite, and many are nocturnally pollinated by moths seeking nectar rewards.

Four species of Oenothera (Primrose) occur here.  O. biennis (Common Evening Primrose) is a tall plant that is fairly common in a variety of habitats (weedy gardens, even shady woods).  The petals of its yellow flowers are heart-shaped (slightly cleft in the middle).  O. rhombipetala (Rhombic Evening Primrose) is a short bushy forb with diamond-shaped yellow floral petals.  It is a ‘special concern’ species in Minnesota but is fairly common along roadsides and in xeric fields.   O. parviflora (Northern Evening Primrose) looks like a small version of O. biennis and O. clelandii looks like a small-petal version of O. rhombipetala.

Six species of Epilobium (Willow Herbs) are found here.  Epilobium angustifolium (Fireweed) is a tall forb with large pink flowers.  It is uncommon at CCNHA, but a superabundant invader of roadsides and burned areas in the northeast part of the state.  The other five species of Epilobium have tiny inconspicuous flowers.  E. coloratum is common in wet meadows and along the sandy shore of Fish Lake during periods of low water.  E. leptophyllum, E. palustre, and E. strictum are inconspicuous inhabitants of peaty marshes.  The identity of E. glandulosum is in doubt and may be a variant of E. coloratum.

Also occurring in this Family are two species of Circaea. C. alpina (Small Enchanter’s Nightshade) is a common species of cedar swamp, and C. lutetiana (Enchanter's Nightshade) is a common weedy species with sticky seeds of woodland trails.  Ludwigia palustris (Marsh Purslane) is an uncommon species of mucky marsh margins.