Do you recognize any of these wildflowers? The one on the left is commonly referred to as Indian tobacco. Its scientific name is Lobelia inflata. The middle wildflower is Cardinal flower with the scientific name of Lobelia cardinalis. And the right-most plant is Great lobelia whose scientific name is Lobelia siphilitica.
Not only do these plants have a raceme of flowers at the top of each plant, they also develop flowers from their leaf axils.
Let’s look more closely at each lobelia’s flower. See what you notice about how similar they are.
What I notice is that each bilaterally symmetrical flower is “two-lipped” with two lobes in the upper lip and three lobes in the lower lip. They also have a long pistil which curves downward so that the tip is over the opening into the deeper parts of the flower where the nectar resides. The stamens are actually fused to the pistil.
You can see this most clearly in the Indian tobacco image above. Here are two more photos which provide closer views of the flower so you can see the unique pistil these lobelias have.
Now, let’s compare the three plants’ leaves and stems. Look carefully . . .
Each lobelia’s leaf has finely toothed margins. They also have what appear to be small white dots along the margin. As for the stems, they have fine hairs. (I realize you may not be able to see this very well with the Great lobelia photo. Click on the third composite image–up above–to see the downy hairs on the Cardinal flower’s stem.)
This last image provides a good view of the white dots along the leaf margin for Indian tobacco. You can also see its hairy stem.