A Close-up View of the "Unsightly Weed"
Curly Dock

(Rumex crispus)

by Brian Johnston   (Canada)

I doubt very much that the average observer cares much about curly dock.  It has little if any of the charisma of its wildflower neighbours.  In fact, the plant may only be noticed in late summer or early fall when the sturdy upright stems and seeds take on an unappealing dark brown, rusty colour.  During the earlier stages of its development, the green flowers are so small, that they are almost impossible to see with the naked eye.  It is only when studied up close, with magnifier or camera, that curly dock distinguishes itself as a plant with quite beautiful, and colourful structures.

Curly dock is a member of the buckwheat family, and grows from 60 to 120 centimetres in height.  The genus name Rumex is derived from the old Latin name for dock or sorrel plants.  The species name crispus also is derived from Latin, and means curly or wavy in appearance.

It is the leaves of curly dock that give the plant its common name.  The image below shows just how curly they really are!

Most of the leaves of the plant are beneath the flowering head shown below.  At this early (bud) stage there are only hints of the red colour in the stem that will predominate later.  It is also possible to see the coloured grooves in the stem.

The buds occur in crowded whorls, one of which can be seen in the image that follows.

A closer look reveals one of the developing buds.  Three outer green sepals, (modified leaves), can be seen clasping an almost spherical white inner core.  This core is actually composed of the three inner, larger, sepals which will turn green as the bud opens.

The two images that follow show a curly dock flower in all its glory.  It has no petals, and is about 3 mm in diameter.  The green petal-like structures are the six sepals that enclose the reproductive parts of the flower.  The anthers (male, pollen producing organs), stand out because of their bright yellow-orange colour.

Although the anthers are easy to see in the image below, the octopus-shaped, pale yellow stigma (female, pollen accepting organ), is harder to make out.  One is visible in another flower to the right of the main one.  The arrow in the second image points to it.

A head-on view of one flower shows the six banana shaped anthers.  The outward curving sepal pointed to in the second image is one of the inner (larger) sepals mentioned earlier.  It is flanked by two smaller inward curving sepals.  This upper sepal and two more at 120 degrees, form the points of an equilateral triangle.  The other small sepal is hidden behind the bottom-most anther.

After fertilization has occurred, the plant soon becomes covered with developing fruit.  Each fruit is a three-sided winged achene (a small seed-like fruit that does not open and contains one seed).  In the three images that follow, the fruit is almost white in colour, and the wings are pale green and veined.

The colour transformations in the achenes as they develop are quite striking.  Fruit a little older than the ones shown above can be seen to have a slight pinkish colouration.

At this stage the stem has become dark red in colour, everywhere except beneath the whorls of fruit!
Several upper leaves can be seen in the left photograph.

The stem above a whorl of achenes has been removed to show how the fruit are attached to the main stem.  Notice that there is a tiny joint in each achene stem, two thirds of the way to the main stem.  It is interesting that the scientific family name of the plant is Polygonaceae, which is derived from the Greek words 'poly' which means many, and 'gonum' which means knee.  Certainly the whorl of achenes displays many of these “knees”.

Later still, the fruit of the achene has become red in colour, as has the edge of the “wing”.

As time passes, the red colouration of the wings increases.

Depending upon how much rainfall has fallen during the summer, plants may develop differently.  The image below shows the brown, (rather than greenish-red) colouration that occurs if there has been insufficient rainfall.

It is at the final stage of development that the plant looks its most “unsightly”.  Strangely, it is now that the achenes are their most striking when observed macroscopically.

Occasionally, malformed achenes are visible.  They too are striking in their unusual structure.

One afternoon, while photographing some achenes, I noticed movement in the Canon 20D’s viewfinder.
An insect visitor was using an achene as a perch!  For five minutes he or she? tried to prevent me from taking his or her? picture by playing “hide and seek”.  As you can see below, I won the game.  It was actually quite difficult, since the insect would stop moving for only a couple of seconds before moving on.  (On a technical note, one advantage of a high megapixel digital camera can clearly be seen in the images that follow.  The second more highly magnified picture in each pair is a crop from the smaller image.  Try doing that with a three megapixel camera!)

It’s commonly said that “there’s no accounting for taste”.  I must admit that curly dock is a great favourite of mine.  I find the dichotomy of its “ugly” appearance when viewed from afar, and striking beauty when viewed close-up, to be fascinating!

Photographic Equipment

An eight megapixel Sony CyberShot DSC-F 828 equipped with achromatic close-up lenses, (Nikon 6T, Sony VCL-M3358, and shorter focal length achromat used singly or in combination), was used to take most of the images. The lenses screw into the 58 mm filter threads of the camera lens. Still higher magnifications were obtained by using a macro coupler (which has two male threads) to attach a reversed 50 mm focal length f 1.4 Olympus SLR lens to the F 828. A few of the photographs in the article were taken with an eight megapixel Canon 20D DSLR and Canon EF 100 mm f 2.8 Macro lens.  (The photographs in the article were taken over a two year period.)


The following references have been found to be valuable in the identification of wildflowers, and they are also a good source of information about them.

 All comments to the author Brian Johnston are welcomed.

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