Tuesday, September 7, 2010

Sunflowers, Coneflowers, and DYC's (part 1)



DYC's?  Yes, Damn Yellow Composites. Let's tell it like it is.  This is one of those difficult groups to get to species. I'm going to attempt to separate many of those I have seen in this area, both wild and in plantings. Rather than deal with a genus all at once, I will use morphological characters to 'try' and keep them apart. Since this is an extremely large subject, I will post in several parts.

A) Does the plant have very showy rays?  (Rays look like flower petals)
B) Are the rays extremely reduced or totally absent?  Let's deal with these first.

A) Majority of leaves simple
B) Majority of leaves compound or divided.

We have a common simple leaved species called Beggar-ticks, Bidens connata

In order to do the others, you have to look at the bracts or Phyllaries. These are the green leaf-like structures surrounding the flower head.

Rays reduced or absent
A) Phyllaries averaging 6-8...Stick-tight, Bidens frondosa
B) Phyllaries averaging 10-12...Stick-tight, Bidens vulgata

Bidens frondosa

Bidens frondosa


vulgata
Bidens vulgata, compare the two species by looking at the amount of green behind the flower head.

Now on to the showier ones.

A) Main stem of plant with distinct WINGS...we'll do these first
B) Main stem of plant without wings...4

1a) Leaves opposite... Crowns-beard, Verbesina helianthoides
1b) Leaves alternate...2


Crowns-beard is a south-central Ohio species not normally found here, but I have seen it in prairie plantings.

Continuing with alternate
2a) Flower heads compact, gumball-like, rays 3-lobed...3
2b) Flower heads loose, spreading, rays unlobed, drooping below flower head...Wingstem, Verbesina alternifolia


Wingstem is too tall to photograph in one shot, so here are the flowers, leaves, and stem. Wingstem is common in bottomlands and wet soils.

3a) Flower heads light colored, yellow-green...Common Sneezeweed, Helenium autumnale
3b) Flower heads dark colored, purple-brown...Purple-headed Sneezeweed, Helenium flexuosum

Common Sneezeweed occurs in various habitats, but I have found it more often in moist soils than the next species.
I see the Purple-headed most often in dry upland soils and prairies.


Plants with most leaves alternate.  What's this 'most' bit. Sorry, some can be both.

4a) Leaves primarily basal, large and broad, up to two feet in length...5
4b) Leaves smaller, more well distributed along the stem...6

5a) Leaves almost as wide as long, elephant ear like...Prairie Dock, Silphium terebinthinaceum
5b) Leaves similar in size but highly divided, looking fern-like...Compass Plant, Silphium laciniatum


Prairie Dock, the classic species of the prairie grasslands. It can grow up to 10 feet tall, and send roots down 10-15 feet. There is one variety whose leaves are divided similar to Compass Plant.

Compass Plant with the very divided leaves. Compass Plant turns itself to follow the sun throughout the day.

6a) Leaves simple...7
6b) Leaves compound or divided...8

7a) Leaves elongate, covered in soft velvety hairs...Black-eyed Susan, Rudbeckia hirta
7b) Leaves shorter, broader, either smooth or with a slight rough touch...Brown-eyed Susan, Rudbeckia triloba


The common Black-eyed Susan. There are many varieties of this used in gardening.




Brown-eyed Susan looks very similar to Black-eyed Susan.  The flower rays are usually shorter, blunter. The stem often turns red, and the basal leaves are often divided (triloba).


Another often planted species is the Orange Coneflower, Rudbeckia fulgida. Looking a bit like both the above, it has egg shaped leaves, and deep yellow rays with a tint of orange throughout, or at the base of each ray.



8a) Leaflets divided into narrow segments, flower head gray/black, rays growing downward, drooping...Gray-headed Coneflower, Ratibida pinnata

8b) Leaflets broadly divided, uppermost simple, flower head yellow/green, rays spreading outward or only slightly drooping...Green-headed Coneflower, Rudbeckia laciniata


Gray-headed Coneflower is a common prairie pioneer species. Over time it will be out competed by other plants.

Green-headed

Look for Green-headed Coneflower in moist soils of shady forests or forest edges.


Those were the easy ones. The impossible opposite branched ones are coming. I only say that because none of them fit easily into a "simple" key, and part two may end up as just species descriptions.






1 comment:

  1. I came across your page looking for some leaf shapes in ID, and wanted to say you are only the second person I've ever heard use the term DYC. I first heard it years ago from a friend (since passed) who used to work for a nursery.

    ReplyDelete