A Close-up View of the

Japanese Toad-Lily

Tricyrtis hirta 'Miyazaki'

by Brian Johnston   (Canada)

The Japanese Toad-Lily is also known as the Hairy Toad-Lily, or Speckled Toad-Lily.  Native to Japan, it was formerly named Tricyrtis japonica.  The modern scientific name, Tricyrtis hirta ‘Miyazaki’, refers to the Miyazaki Agricultural Station associated with Miyazaki University in Japan.  Like other Toad-Lilies, it blooms late in the summer or early fall, and continues to bloom until a hard frost occurs. The plant prefers part, to full shade, and this makes it useful for gardeners with an abundance of trees on their property.

Although the flower structure is identical to the Toad-Lily described in an earlier article,  the plant’s colouration is dramatically different.  Its leaves are light green, or yellow green, and the flowers are much lighter, resulting in a completely different appearance, not only close-up, but also from a distance.  The stems initially grow upright to about 50 centimetres, but eventually, the weight of the blooming flowers causes them to arch gracefully in random patterns.

Tricyrtis hirta ‘Miyazaki’ frequently hybridizes with other cultivars growing in close proximity, producing blooms with unpredicable patterns and colourations.  The resulting plants are called “Miyazaki hybrids”.

As you can see from the first image in the article, and the two that follow, the entire colouration of the plant is more muted than in other Toad-Lily cultivars.  The leaves are a very light yellowish-green, and the flowers are white to pale lilac with many randomly shaped, lavender spots.

Also noticeable is the extremely tight spacing of leaves, buds, flowers, and seed-pods near the top of the plant’s stem.

The arrangement of buds and flowers on the stem is rather unusual, as can be seen in the font and back views below.  At the top of the stem, there is a tightly packed group of blooms.  As you move down the stem, there is a bud located at the axil (point of connection) of each alternately positioned leaf.  Leaves like these that have little or no stalk, and that curl around the stem at their base are called “clasping”.

These clasping leaves are visible beneath the blooming flowers at the top of the stem.

A closer view shows the red base of each leaf, and its intensely hairy surface.

The fine hairs can be seen more clearly in the higher magnification images that follow.

Notice below, the progression in the blooming process from bottom to top in the images.

The two flowers shown below are almost mature. Their sepals and petals will eventually bend back until they are almost at right-angles to the stalk that holds the flower’s reproductive structures.

Japanese Toad-Lily’s buds are colourful sculptural jewels, with their swollen spurs producing a rocket-ship-like appearance.

It’s easy to see why one of the common names of the hybrid is the Hairy Toad-Lily.  Even the surface of a bud is remarkable hirsute!

Many of the fine hairs have a microscopic droplet of liquid at their tips, leading one to suspect that the hairs are glandular.

The image below shows the outer sepals of the lowest bud opening to reveal the petals beneath.

If you look at the topmost flower in each of the following images, you can see the column of red-spotted filaments that surrounds the ovary.  At the top of each filament there is a pale beige, oval anther.

The flower’s three styles grow up inside the column of filaments, and branch out to form three forked structures with a stigma pad at each tip.

By removing a sepal and petal, the column formed by the six filaments becomes easier to see.  The ovary, and the lower ends of the styles are hidden within this assembly.

The arrangement of the flower’s six anthers is not as “neat and tidy” as it is in the hybrid studied in the earlier article

Notice the great variation in spot size on the surface of a petal.  In the image on the right, numerous pollen grains can be seen clinging to the petal’s surface.

Most, if not all Toad-Lily hybrids have glistening glandular structures along the edges of the styles.

The top surface of the flower’s oval anthers matches the surface texture and colouration of the rest of the plant.  Even the supporting filaments are purple-spotted.

Here is a very high magnification macro-photograph that shows the glandular structures covering the edges of styles.  Liquid appears to be pumped into the membranous spheres through the stalks that support them.

One of the two stigma pads on a forked style can be seen curving down toward the top of an anther in the three images that follow.  Notice the stubby, hair-like protuberances that cover the stigma.  These increase its surface area, and help retain pollen grains.

A side view of an anther shows that its lower, active surface is covered with pollen grains.

After fertilization, the flower’s three-sectioned ovary begins to increase in size dramatically.  At first, it is partially hidden by the remnants of sepals and petals, but these eventually fall away to reveal the light-green, seed producing structure.

Although this hybrid is certainly unusual, it is in my opinion, not as striking as the other Toad-Lilies that I have seen.  Its colouration makes it much more difficult to differentiate between its structural components. 

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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