10/14/2014 6:49 PM
There are two onions in Drumheller Springs
Park
Allium acuminatum, Hooker’s onion, taper-tip onion. They
have both been moved from the Liliaceae family to the Amaryllidaceae family.
Their anthesis [I finally remembered that word when I wanted
to use it … their flowering period.] does not over lap. A. geyeri is earlier,
A. acuminatum is later.
Paul Slichter says: A. acuminatum “… is the most common and
widespread of our Pacific Northwest onions. It
is commonly found in thick drifts, and may paint whole hillsides pink when in
bloom.” Paul apparently lives in the Willamette
Valley , much wetter country than Spokane . However, his
photos are ‘dated’ in eastern Washington as
well as Western Oregon .
Allium geyeri is the more common onion in Drumheller Springs
Park
This damned word processor won’t let me put A. geyeri as the
first word in a paragraph without assuming it’s a list and indenting it and
succeeding lines. Ok, I could read some documentation. Ugly thought.
Lots of the photos of A. acuminatum on other sites show
rather lurid red-purple tepals. Few show white tepals with a red-purple streak.
My photos of A. acuminatum are tepals that are a light pink and striped.
Reminder - tepals
The usual configuration of a flower has petals around the
reproductive organs forming a corolla and sepals, often green and leaf like,
around the petals forming a calyx.
The corolla and the calyx are also called the inner and
outer perianth. If there is only one perianth or if the inner and outer
perianth are similar botanists use the term ‘tepals’, an anagram of ‘petals’.
The two three-tepal perianths of Allium are roughly similar
in appearance.
*
Allium geyeri is usually pink to light red. Sources say they
are rarely white. There are fewer white in the park but they are not rare.
Allium are monocots so their flower parts are in 3s and 6s.
The inflorescence for onions is an umbel. My available
photos show A. geyeri’s umbel with shorter pedicles. The flowers look tighter
and they have more flowers than the umbel of A. acuminatum.
My internet resources are conflicted on the number of
flowers in an umbel. There is some agreement on other issues of identification.
As is always the case. I need more and better photos next
year.
My best photo of an Allium geyeri umbel is a photo of a
white variety. All of my photos have the pedicels quite short on A. geyeri when
it is in flower, the flowers are compact. The photos of dry husks have pedicels
that are longer. So perhaps it is an accident that I photographed only early A.
geyeri in bloom. That would be consistent with searching for the earliest plant
in bloom of every species.
The thickened receptacle at the top of the flower stalk is
well represented in the photo below. The white structures dangling from the
receptacle are referred to as bracts by my sources. They look, here, a little
like the phyllaries of an involucre. But in other photos it seems the role of
involucre is played by a thin, enclosing, membrane, not a circle of green
bracts as in an ordinary involucre [Involucre – like a calyx but at the base of
an inflorescence rather than at the base of a flower.] In the photo below the
membrane looks torn away, not like re-curved bracts [phyllaries] of an
involucre.
Again, the botanists call tepals, what we would call petals.
There are two rings. I wonder if the green base on the outer ring of tepals
suggests remnant sepals, what’s left of a calyx.
Allium geyeri, white
010
I’m fairly sure the photo below is A. geyeri, gone to seed.
I believe the many flower stalks identify it. The pedicels are as long as those
of A. acuminatum.
There is one seed showing just to the right of center.
020
I believed this was late stage A. geyeri when I processed
the photo but now I think the smaller number of flowers identifies it as A.
acuminatum, even though the outer ring of tepals are not distinctively
re-curved on most of the flowers. But the central flower, the newest flower, the
one on the shortest pedicle, does have the distinctive spread outer tepals of
A. acuminatum.
[Burke says of both plants that the pedicels are of equal
length. That doesn’t seem to be true in my photos. Even the husk umbel in the
previous photo has shorter pedicels on the central flowers.]
030
The photo below is the inflorescence of A. acuminatum in an
early stage. The newest flowers of the umbel are very clearly the central
flowers. Hmm. I assume the fully developed flowers were once the ‘leading bud’
and were central flowers and that they have been pushed aside by successive
leading buds. An umbel is an indeterminate inflorescence.
040
These photos are A. geyeri flowers. The tepals of the outer
ring are re-curved but not so much.
050
The resolution isn’t good enough to show a wavy character to
the inner ring of petals, never mind the minute teeth that would identify A.
acuminatum if they existed. Assume they don’t exist.
060
The flower of A. acuminatum.
070
080
090
I don’t see the wavy character of the margin of the inner
tepals mentioned by Paul Slichter but we may see his minute teeth on the margin
of the inner tepals. Hmm. The inner tepals curve to a point [A. acuminatum -
from acuminate, narrowing to a point, they are ‘taper tipped’, their ‘common
name’].
100
The resources have detail on the ovary, the styles and the
stigma that cannot be seen in my photos. The ovary of A. geyeri is
‘inconspicuously crested’. The ovary of A. acuminatum is crested. There is more
detail, especially in Flora of North America. It is too difficult for me to
understand or it is too poorly written to understand. I suspect the latter.
I have no clear photos of the stigma of A. acuminatum. The
stigma of A. geyeri is said to be capitate or obscurely lobed. The stigma of A.
acuminatum is said to be obscurely three lobed.
*
Both plants have a scape, a stem with no leaves. Both plants
have basal leaves. But the basal leaves of A. acuminatum wither at anthesis.
A. acuminatum, basal leaves absent during anthesis
110
120
A. geyeri, basal leaves present during anthesis
140
150
Paul Slichter says A. acuminatum grows in ‘thick drifts’.
Not in Drumheller
Springs Park
160
I don’t have photos of A. acuminatum in bud. Gerald Carr has
a nice comparison photo of buds of A. geyeri, A. acuminatum and A. douglasii
I have lots of photos of A. geyeri in bud.
Often its bud seems to be enclosed in a smooth membrane
170
But here it looks a little more like an involucre, phyllaries
fused at the base, with an indication of separate points at the top. If they
are bracts they do not look leaf-like.
180
Phyllaries are not apparent, here, but it looks like there
are weak places in the covering.
190
Looks like this one got sick.
200
Pink A. geyeri buds opening
In the following series the covering looks a lot more like a
membrane has split and been pushed down by the expanding flowers than like phyllaries
have re-curved to permit the expansion of the flowers.
210
220
230
240
250
I suppose that’s an aphid.
260
White A. geyeri buds opening
270
280
290
300
The leaves develop early. The flower stalks develop later.
The flower stalks will be longer than the leaves.
310
320
I have no photograph of A. acuminatum in fruit or an A.
acuminatum husk.
A. Geyeri inflorescence in fruit
330
A fruit. If we could see the other septa [points of division
on the fruit] we would see that there are three sections.
340
I suppose these are the outer tepals, dry
350
The prominent ridge suggests strength, the tepals functioning
as if they were protecting sepals, a calyx.
360
Top view
An inadequate attempt to show the three locules
[compartments] that contain the seeds.
There should be six seeds, two seeds in each of three
chambers.
370
The seed
380
Flora of North America says of A. geyeri: “… not producing bulbils, or
0–5-flowered, largely replaced by ovoid, acuminate [pointed] bulbils; …”
Flora of North America says of A. acuminatum: “…bulbils unknown; …”
We have to watch for bulbils next year.
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