September 18, 2011, 4G = Great Goldenrod Guessing Game

Tower at Bonneyville County Park

From 5-6 p.m. this evening I was near the lookout tower at Bonneyville Mill County Park trying to figure out the Goldenrods in the vicinity of the parking lot.  Not all Goldenrods are the same!  Yatskievych's Field Guide to Indiana Wildflowers describes 15 Goldenrod species in our area.  It is a challenge for me, amateur that I am, to figure them out.  I depend primarily on Newcomb's Wildflower Guide for identification.  Some of the species have unique characteristics that make them relatively easy to figure out, but others differ only in small details.  I will appreciate comments on the following identifications. [You may click on the photos to enlarge them.]

Canada Goldenrod, Solidago canadensis

The most common species, Canada Goldenrod, is on all sides of the lot. The numerous small flower-heads are "in curved, one-side clusters, together forming a large terminal cluster" (quoting Newcomb's Guide). 

Grass-leaved Goldenrod, Solidago graminifolia

The stem of Grass-leaved Goldenrod is branched at the top, forming a flat inflorescence.  Both Canada Goldenrod and Grass-leaved Goldenrod grow in a wide variety of habitats.

Rough-Leaved Goldenrod, Solidago patula

Rough-Leaved Goldenrod grows primarily in wet habitats; it grows in the wet ditch just across CR 108 from the parking lot entrance. (See what was blooming in this same spot in the May 16 blog entry.) The large, sandpaper-rough lower leaves of Rough-Leaved Goldenrod make it easier to identify than most other Goldenrods.

Large lower leaves of S. patula

S. patula flower clusters

Also growing in the same wet ditch is what I identified as Late Goldenrod, Solidago gigantea.  

Late Goldenrod, Solidago gigantea

Late Goldenrod is so similar to Canada Goldenrod.   I identified it as Late Goldenrod primarily because it grows in a wet area and its flower heads appeared a tad bigger than those of S. canadensis.  But I may be wrong.

Flower heads of Soldago gigantea, clustered on one side of stem

Just inside the woods to the west of the parking lot I spotted what I identify as Elm-Leaved Goldenrod, Solidago ulmifolia.  The lower leaves are large and sharply toothed.

Elm-Leaved Goldenrod, Solidago ulmifolia

Terminal cluster S. ulmifolia flower heads

 By now you may have more information on Goldenrods than you want or need - a good place to stop.