Close-up view of the wildflower heal-all, Prunella vulgaris
View of the Wildflower
by Brian Johnston (Canada)
This extremely common plant is found
worldwide, and may grow as tall as 40 cm in the “wild”, or as short as
2 cm in locations such as your lawn, where it is frequently cut or
mowed. Its common names, Heal-All, Self-Heal, and Cure-All are a
reference to its use in “herbal medicine”. Wouldn’t it be
wonderful if the appellations were actually correct! (I suspect
that the “-All” part might be a slight exaggeration!)
Prunella vulgaris is a member
of the mint family (Lamiaceae).
botanists refer to two varieties of the species, the European one
being called vulgaris, and
the North American one being referred to as
lanceolata. Both species
grow in most locations, and since they
are almost indistinguishable, the particular species name is not overly
important for this discussion.
The image above shows a Heal-All flowerhead in full bloom. The
many shades of purple, violet, and green make this a very attractive,
(but small), wildflower.
Two images of the bud-stage of the flowerhead, (inflorescence), can be
seen below. The structure is composed of parts that are so
tightly packed, that they are difficult to distinguish. Keep in
mind that the inflorescence of Prunella
vulgaris is described as a
flowers are borne in rings, (or whorls), of
decreasing diameter at intervals up the stem. As the tip of the
stem continues to grow, additional whorls are added. This type of
inflorescence is common in members of the mint family. In the
images, there are green leaflets indicating each new level, and
reddish-purple sepals (modified leaves) that are flattened into an
envelope, from which the buds and flowers will emerge.
When a flower blooms, its pale purple petals emerge from the sepal
Notice that the top of the verticillaster is flattened. In most
flowerheads, the blooms are arranged vertically in rows, at
right-angles to one another.
Other Prunella vulgaris
plants, like the one shown in the images that
follow, look quite different. This is an example taken from a
lawn which is cut frequently. The purple colouration of the
bracts doesn’t have enough time to intensify, and so the flowerhead
appears much greener than the earlier one. Also notice that the
flowers are not arranged in the perfect four-fold symmetry of the
Heal-All flowers have two petal-lobes, forming an upper lip that is
hooded, arching out over the stamens, and a lower lip which is less
intensely coloured. Notice that the sepal pockets have a sharply
pointed fringe. The green leaflets are also fringed, but this
time with long white hairs.
A front and side view of a blooming flower can be seen below.
Beneath the upper and lower lips, the flower’s petals are fused to form
the corolla tube.
Under the upper, hood-like lip are the flower’s four stamens, arranged
in two pairs – an upper and lower. The flower’s pistil grows
between the two upper stamens, but it is difficult to see in this image.
In the closer view at left, below, one of the stigma’s two lobes can
just be seen beneath the hood, projecting down like a fang. In
the view on the right, the entire stigma is visible, with both its
lobes, in the middle of the group of anthers.
Speaking of anthers (male pollen producing structures), here is a
photomicrograph showing one. A multitude of white pollen grains
sit on the top surface, which is purple in colour. Between the
white base and the purple top, is a light blue band. The forked
filament that supports the anther is also present in the image.
Closer views of Heal-All’s pollen grains can be seen below. Each
is ellipsoidal in shape, and has a noticeable longitudinal groove on
Here is a much better view of the forked stigma, (female pollen
accepting organ), positioned between the upper two anthers.
Under the microscope, each lobe has adhering pollen grains.
Higher magnification views of a stigma lobe follow. In the first
image, you can see that part of the lobe’s surface is covered by thick,
Segmented hairs growing from the top surface of the flower’s upper
petal are shown below.
Once a flower has bloomed, the wind, or some other disturbance, causes
it to fall out of the sepal pocket. The pocket then looks like a
bulged open envelope. Examples of these flowerless envelopes can
be seen below. (Purple-fringed sepals, like those shown below,
tend to occur more in “wild”, rather than “lawn” plants.)
For comparison, here is an example showing a lawn flowerhead that has
completely finished blooming.
The plant’s leaves are lance-shaped (lanceolate), and are positioned
opposite one another.
Upper and lower views of a leaf’s surface are shown below. Notice
the extremely tiny hairs that grow on the leaf’s edge, and on the
prominent vein on its underside.
In my area, Heal-All plants begin to bloom in early May, and continue
until the end of September. They are truly ubiquitous – I have
found them in the most unlikely places! Unfortunately, many are
so small, that a passerby might miss them. The next time you go
for a walk, look for them. They are worth a close-up view!
Approximately half 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. An eight megapixel Sony CyberShot DSC-F 828 equipped with
achromatic close-up lenses (Canon 250D, Nikon 6T, and Sony VCL-M3358
used singly, or in combination), was used to take the remainder of the
The photomicrographs were taken with a Leitz SM-Pol microscope (using a
dark ground condenser), and the Coolpix 4500.
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.
- Dickinson, Timothy, et al.
2004. The ROM Field Guide to Wildflowers of Ontario. Royal
Ontario Museum & McClelland and Stewart Ltd, Toronto, Canada.
- Thieret, John W. et al.
National Audubon Society Field Guide to North American Wildflowers -
Eastern Region. 2002. Alfred A. Knopf, Inc. (Chanticleer Press,
Inc. New York)
- Kershaw, Linda. 2002. Ontario
Wildflowers. Lone Pine Publishing, Edmonton, Alberta,Canada.
- Royer, France and Dickinson,
Richard. 1999. Weeds of Canada. University of Alberta
Press and Lone Pine Publishing, Edmonton, Alberta, Canada.
- Crockett, Lawrence, J.
2003. A Field Guide to Weeds (Based on Wildly Successful
Plants, 1977) Sterling Publishing Company, Inc. New York,
- Mathews, Schuyler F.
2003. A Field Guide to Wildflowers (Adapted from Field Book
of American Wildflowers, 1902), Sterling Publishing Company, Inc.
New York, NY.
- Barker, Joan.
2004. The Encyclopedia of North American Wildflowers.
Parragon Publishing, Bath, UK.
A Flower Garden of
A complete graphical index of all
of my flower articles can be found here.
The Colourful World of
A complete graphical index of all
of my crystal articles can be found here.
Microscopy UK or their contributors.
Published in the
November 2010 edition of Micscape.
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