A close up view of the chrysanthemum

Before the white chrysanthemum
the scissors hesitate
a moment.

Yosa Buson
(1716 - 1784 / Japan)
Translated by Robert Hass

The seemingly strange name for this plant derives from the Greek “krus anthemon” which means “gold flower”. Although chrysanthemums can be found today with most of the colours of the spectrum, the first cultivated plants mentioned by Confucius about 500 BC did have small yellow blooms. Chrysanthemum cultivation is thought to have originated in China or Japan. The Chinese considered it to be the ultimate flower, and thus gave their throne the same name.

The flowers of a chrysanthemum are typically clustered over the top of the plant where they may be so abundant that they almost obscure the leaves beneath. Flowers of different plants may possess a wide range of visual characteristics. The petals may be daisy-like, narrow and lacy as in the spider form, flat and spoon-shaped, feathery, or even quill-shaped. The flower photographed for this article appears to be a hybrid of quill and spoon forms.

I chose this particular plant because of its striking colouration, with brilliant purple-red spoons, and pinkish-white quills. Chrysanthemums belong to the largest plant family on Earth – the aster family (Asteraceae). Members of this family usually possess both inner disk flowers, and outer ray flowers. Thus each of the blooms that can be seen below is composed of many individual flowers (or florets).

The three images that follow show a chrysanthemum bud. Notice that the intense colour of the final flower is nowhere to be seen in the bud form. The final image shows clearly the ring of bracts (modified leaves) that encloses the developing flowers. Notice that the centre of each bract is green in colour, and that there is a white band separating the centre from the dark brown edge.

The green leaves are lobed and possess teeth around their margins. The photomicrograph at right shows the cellular structure of the upper surface of a leaf.

Each leaf’s lower surface is composed of cells with a distinctive jigsaw appearance. Only the lower surface possesses the soft hairs that can be seen in the right-hand image.

At an early stage in the blooming process, the outer quill-shaped disk flowers have yet to move into their final position roughly perpendicular to the stem. Note the multiple rings of bracts that enclose the bases of the flowers.

Under the microscope, the outer edges of the bracts appear translucent, and have irregular shapes.

Some of the fine hairs that coat the outer surface of the green middle section of a bract can be seen in the photomicrographs below.

As mentioned earlier, the outer disk flowers of this chrysanthemum have a long, tubular quill shape with an oval opening at the tip. At the bottom end of each tubular flower is the pistil, (the female reproductive structure).

The three lobes of the stigma (the pollen accepting organ) are initially parallel to one another (left image). Later, they separate into the positions shown in the right-hand image. The style that supports the stigma can be seen at the bottom of each image.

Higher magnification reveals that the surface of each lobe is covered with dome-shaped protuberances.

Beneath the style is the cylindrical ovary in which the flower’s fruit, (or seed), forms. (The style has been removed for this image.) The stalk that connects the ovary to the base of the flower-head is visible in the image to the right.

Between the outer ray flowers, and the inner disk flowers, there is an intermediate ring of shorter quills with spatulate (spoon-shaped) tips. These flowers contribute greatly to the flower-head’s striking appearance.

Notice how the edge of the quill’s opening is ‘rolled’ outwards.

The two photomicrographs that follow show the cellular structure of one of the spoon-shaped petals. The image at left is ‘true’ colour, while that on the right was given a ‘levels’ adjustment in Adobe Photoshop to enhance contrast, and accentuate detail.

In the occasional petal, there is some green colour along with the red. The higher magnification image on the right shows the ‘banded’ surface appearance of each cell.

Some of the cells at the topmost edge of a quill can be seen below.

Each flower on the plant is subtly different from the others. In the bloom below, there are approximately equal numbers of quill and spoon flowers.

Other blooms have more spoon flowers than quill flowers.

At the centre of the flower-head, the tubular base of each spoon flower is so short that the flowers seem to have simple oval petals.

Strangely, although I searched long and hard for male stamens in the chrysanthemum flower-heads, I was unable to find any. Perhaps an interested reader could give me a hint as to where they might be found!

Although chrysanthemum blooms are very diverse in structure, one can always identify the genus with the aid of one’s nose. Their unusual, and very distinctive scent gives them away!

Photographic Equipment

The macro-photographs were taken with an eight megapixel Canon 20D DSLR equipped with a Canon EF 100 mm f 2.8 Macro lens which focuses to 1:1. A Canon 250D achromatic close-up lens was used to obtain higher magnifications in several images.

The photomicrographs were taken with a Leitz SM-Pol microscope (using a dark ground condenser), and the Coolpix 4500.

A Flower Garden of Macroscopic Delights

A complete graphical index of all of my flower articles can be found here.

The Colourful World of Chemical Crystals

A complete graphical index of all of my crystal articles can be found here.

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