A Close-up View of the

Newport Plum Tree

Prunus cerasifera 'Newportii'

by Brian Johnston   (Canada)

Trees, like clothing, move into and out of fashion.  At the moment, the Newport Plum tree is decidedly fashionable.  Many of my neighbours have planted this relatively small ornamental tree on their properties because of its startling colouration.  Few trees maintain this deep purple foliage throughout the growing season, from early spring, to late fall.  Growing to about 5 metres in height, it possesses remarkable hardiness, even in the frozen winter wilderness of Southern Ontario.  (I may have exaggerated just a little!)

An added bonus provided by the tree is the profusion of pinkish-white flowers that bloom in early spring (image above).  The two images that follow show this spectacular display.

In fact, the intensity, and depth of colour of the tree’s foliage makes one wonder whether some prankster has done an exceptionally detailed spray-painting job!

Closer views reveal that the tree’s leaves are oval in shape, and minimally serrated.  Notice that the new growth stems and stalks match the leaf colour, while older branches are a more mundane light brown.  The off-white colour of the flowers provides a striking contrast with the leaves.

While examining the six images that follow, notice the oval shape of a flower’s petals.  Five such petals form the flower’s corolla.  At the centre of the corolla is a bright red disk from the circumference of which numerous bright orange stamens grow.  At this magnification it is difficult to detect the flower’s pistil.

If you look carefully at the two central flowers in the image below, you will be able to see the single yellow-brown stigma near the centre of the disk.

Immediately beneath the petals of the central flower seen below, is evidence of a whorl of pale green sepals (modified leaves) that protects the petals in the bud stage.

In some flowers these sepals are bent back, while in others they are in contact with the petals.  Notice that the sepal’s ‘upper’ surface is green in colour, while its ‘lower’ surface is purplish-green.  Also note that the sepals are positioned between the petals.

Shown below is one of the tree’s buds.  As mentioned earlier, the whorl of sepals, (called the calyx), protects the tightly packed petals and reproductive structures.  Immediately above the bud’s stalk is the lumpy ovary.

As the buds begin to open, the sepals separate, and the growing petals begin to unfurl.  Notice the strangely shaped glandular hairs, with bulbous tips, that grow from each sepal’s edge.

Closer examination of a flower reveals numerous orange, lobed anthers supported by paler hair-like filaments.  You may also be able to identify the single yellowish brown stigma in each image.

In the newly opened bloom seen below, the anthers have not yet begun to release their pollen.  At this early stage, the anther’s surface is covered by a thin membrane that later disintegrates to reveal the pollen.  The second image also shows the irregularly shaped upper surface of the flower’s stigma.

Additional images showing these multi-lobed, membrane covered anthers follow.

Eventually the membranes begin to disintegrate, and surprisingly smaller, pollen covered anthers are revealed.  Note that the pollen grains are distributed unevenly over the surface of the anther.

The next group of images shows a flower’s single pistil, composed of a bright red columnar style which supports an irregularly shaped, partially folded, light brown stigma.

Both groups of leaves and flowers appear to grow from bumpy nodes along the length of a branch.  Note that the groups of flower stalks are at right angles to the group of leaves in both images.

The sequence of images that follows, taken with increasing magnification, shows in more detail one of these ‘growth points’ along the stem.

Another similar sequence reveals an oval scar, from which a group of flower stalks or leaves has fallen.

Finally, here are three images that show the veined under-surfaces, and oval shape of a Newport plum leaf.  The finely serrated edge of a leaf is visible in the third image.

The particular hybrid Prunus cerasifera ‘Newportii’, the subject of this article, was introduced in 1923 by the University of Minnesota Horticultural Research Centre.  It is a cross between Prunus cerasifera ‘Atropurpurea’ and Prunus cerasifera ‘Omaha Plum’.

Photographic Equipment

The low magnification, (to 1:1), macro-photographs were taken using a 13 megapixel Canon 5D full frame DSLR, using a Canon EF 180 mm 1:3.5 L Macro lens.

A 10 megapixel Canon 40D DSLR, equipped with a specialized high magnification (1x to 5x) Canon macro lens, the MP-E 65 mm 1:2.8, was used to take the remainder of the images.

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.

 All comments to the author Brian Johnston are welcomed.

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