Friday, May 24, 2013

Native Species Profile - Swamp Buttercup

As the end of May approaches, Mid-Michigan is in a lull when it comes to wildflowers.  Most Spring ephemerals are done blooming and the Summer wildflowers have not started yet. Two weeks ago, when you walked into any swamp or wet woodland you were probably greeted by a carpet of Marsh Marigolds (Caltha palustris).  If you enter the same habitat today, you might still find the occasional late-blooming Marigold, but any bright yellow blooms that you find are more likely to be a Buttercup (Ranunculus sp).

There are eighteen species of Ranunculus in Michigan, so narrowing them down can be a challenge.  Most of the species have very short petals so two-thirds can be eliminated immediately when trying to identify this plant.  Of the remaining six species only only three occur in Mid-Michigan.  Of the remaining three, R. fascicularis only occurs in upland sites.  That leaves R. acris and R. hispidus as possible species.  Both species of plants favor wetlands so habitat alone cannot be used to identify them.

To complete the identification, you have to look at the leaves.  Tall Buttercup (Ranunculus acris) has simple, deeply lobed leaves.  Swamp or Bristly Buttercup (Ranunculus hispidus) also has deeply lobed leaves, but on R. hispidus the leaves are compound with the terminal lobe (leaflet) having a definite stalk.  Because these plants have compound leaves that gives us Swamp Buttercup as our identification.

Swamp Buttercup (Ranunculus hispidus)

The Swamp Buttercup blooms from April into July.  Its flowers are approximately 1/2 to 1 inch across.  The petals are widest their midpoint and are up to twice as long as the sepals.

Swamp Buttercup (Ranunculus hispidus) - note the petals are widest past their middle
 The plant itself can be found in a variety of wet habitats including wet woodlands, swamps, wet meadows, and the banks of streams.  It can grow to a height of 1 to 3 foot, but tends to sprawl or trail unless supported by other vegetation.

Swamp Buttercup (Ranunculus hispidus) - note the compound leaves

Swamp Buttercup (Ranunculus hispidus)

Basic Information

Swamp Buttercup
Ranunculus hispidus

Height:  1-3’ tall

Habitat:  wet deciduous woodlands, wet meadows, swamps, banks of streams and rivers

Flower Color:  yellow

Bloom Time:  April – July

No comments:

Post a Comment