SYCs review

OK a couple of readers don't quite get the disk/ray flower thing that TPP mentioned in last week's FFF on goldenrod.  So here is a better example, the ordinary sunflower, Helianthus annuus.  This is not a flower, it is an inflorescence that mimics a flower's image.  When you have little flowers, best to group them together because the bigger the display, the more visitors you get, the more pollination, and so on and so forth (my major professor always used to say that when he thought the explanation was obvious).  At any rate what appear to be petals are a ring of ray flowers with one long corolla lobe making the ray flowers highly bilaterally symmetrical.  They surround a spiral array of radially symmetrical disk flowers.  The inner most ones are still unopened buds, so start taking a close look at those composite "flowers".  Dandelions have all ray flowers, and others have nothing by disk flowers.  Enjoy.  

Friday Fabulous Flower - Compass Plant

As mentioned yesterday, the prairie is in bloom, and given the reasonably abundant rain, the vegetation is lush and tall.  The compass plant (Silphium laciniatum) is one of the prairie emergents whose inflorescence emerges above the other prairie vegetation at least at this time of year.  The inflorescences are around 6-6.5 feet tall and it is just beginning to flower, and as this image shows it is quite stunning.  Each "flower" is actually an inflorescence typical of the sunflower/aster family.  The image of a flower, and without question the image floral visitors react to is the whole "bloom", is presented by the ray flowers around the periphery each with a strap-like corolla lobe and the central disk flowers each with a smaller 5-lobed corolla.  Each "bloom" is around 3 inches across.  This is a common enough strategy; when you have small flowers, cluster them together for a bigger display. 

Friday Fabulous Flower - Globe Thistle, a drought survivor

While lots of plants are looking rather sad, the globe thistle (Echinops and uncertain of the cultivar or its origin), while a bit shorter than usual, is flowering pretty normally.  These are tough plants and quite drought tolerant, up to a point, and the upper midwest is getting to that point awfully fast.  As you can tell from the inflorescence, this is a member of the Aster or Sunflower family.  Rather than forming a flat head, the globe thistle gets its name from having a globose head.  It also has no ray flowers, the ones that form the "petals" in sunflowers.  This one is just beginning to flower and it will attract a pretty wide array of visitors.  The individual flowers with 5 corolla lobes are pretty easy to see while in things like sunflowers you have to look much closer.  The plant's foliage is a bit coarse, thistly, so best to plant them among other perennials of similar height.  It's good to have some tough plants around that will provide some color no matter what.

Ligularia in flower

Midsummer means lots of lilies and ligularias in this instance Ligularia japonica are in flower. It should be obvious that this is a member of the sunflower family, but that isn't so obvious to everyone. A recent visitor remarked, "Oh, that one has a big flower." In fact the flowers are pretty small, but they are grouped together into a large flat disk of an inflorescence that produces the image of a large flower. Each of the yellow "petals" is an individual ray flower whose corolla is a big strap shaped affair narrowing at its base to a little tube. The rest of the flowers are disk flowers with short symmetrical corolla tubes and you can see unopened disk flower buds in the center. So there are several dozen flowers open. The style extends out of each flower and the bilobed style makes a double loop at the top. Flowers open first around the margin (bottom) and proceed to open in towards the middle (top). No question that insect pollinators are reacting to a "floral" image presented by this inflorescence.

Friday Fabulous Flower - Yellow Coneflower

The sweltering heat and humidity of the midwestern summer season are upon us, and many of my exotic babies, natives of milder climates, suffer, while a few plants hailing from more southern climates, rejoice. But the plants that do best, year in and year out, are natives. So this friday's fabulous flower is a native of the tall grass prairie, the yellow coneflower (Ratibida pinnata). Some people confuse the yellow coneflower with the black-eyed susan, which is in another genus altogether. Both are members of the sunflower family, so actually this isn't a fabulous flower, but a fabulous inflorescence composed of brown radially symmetrical disk flowers centrally and yellow bilaterally symmetrical ray flowers appearing like petals (as in "she loves me, she loves me not") around the periphery. The yellow corollas of ray flowers droop downward (as shown), while the corollas of black-eyed susans are held more or less out at right angles (there are other differences too). The disk flowers in the center (top) of the button haven't opened yet. Inflorescences like these present the appearance of a single flower because that's the point, to cluster a bunch of small flowers in such a way as to present a bigger display. Pollinators always looking for the biggest reward are attracted to bigger displays, and inflorescences like these are one way plants with small flowers enhance their attractiveness and reproductive success.