I was only out a little over an hour and most of that time I
was doing photography in the shade. The computer says the temperature was 15 to
20 degrees above normal and it is to stay that way for a few days. I suppose it
was about 85 degrees, very hot for sudden spring heat.
106 images. 46 keepers. Less, really. Some are twice cropped
for fake close-ups.
I drove to the west end of the park to see if the Apple tree
was in bloom. It didn’t seem to be from the distance but actually the
blossoming had come and gone. I saw only 2 whold blossoms. I destroyed one
trying to photograph it.
The tree didn’t seem to ever have had many blossoms this
year. I think I remember that it was loaded with apples last fall.
*
When I arrived at the park one of the shrubs of import
corner was packed with yellow blossoms. It turned out to be the real, Purshia
tridentata, antelope bitterbrush.
I had misidentified a shrub as P. tridentata. Grant had told
me how sweet its odor was. The shrub I thought was P. tridentata was not sweet
smelling.
The real P. tridentata is very sweet smelling. The bugs love
it. But I wasn’t into bug photography in the heat. Too bad. Great light for it.
My main objective was a little exercise. I got very little.
It was too unpleasant in the spring heat.
One of several secondary objectives was to make photo-sense
of the two currently blooming Lomatium. I took several specimen of L.
macrocarpum and photographed them. I got only a ‘patch’ photo of L.
triternatum. Walking toward the apple tree I noticed Microsteris gracilis,
slender phlox here and there. I took one.
Ben Legler’s notes below his photo of M. gracilis for Burke
Herbarium points out branched stems. My specimen had a single stem. I need to
watch to see if branched stems is the usual thing for our M. gracilis.
There is a huge Cornus sericea, red osier dogwood behind the
apple tree. Burke says its habitat is moist soil. This area is quite dry. But
it may get enough water from the lawn behind it. It’s huge … high.
I wondered if it was the same species as the C. sericea in
south pond. They seem to be restricted to areas flooded in spring and as I
recall them, they do not grow high. I need to verify that.
The buds on this one look as if they will bear the same
flowers as those in south pond. The other two Cornus shown in Burke have
radically different looking blossoms.
I took a specimen of Camassia quamash to try, once again for
a photo of a stigma.
I took a specimen of the unidentified shrub [Cercocarpus
ledifolius, thank you EcoRover] in import corner
for photos of the fruit.
I carried my specimens back to the car. I faked a worktable
on the back of my station-wagon. I was very pleased with myself, till I got the
photos into the computer.
I actually realized at the time that I was working in three
levels of shade, the shade of a high hedge, the shade of the station-wagon
itself and the shade of my camera and I. But I thought I was getting away with
it. And I did, to some extent, because it was convenient to brace the camera
for slow shutter speeds. But some photos need to be reshot.
All I had to do was turn the car around so I had southern
exposure instead of northern exposure but I didn’t think of that at the time.
*
I stopped, as usual, at Skippers on the way home for a bowl
of chowder.
I asked for a senior discount. The young scoundrel said I
was too young for a senior discount. I didn’t think to offer him my I. d.
It occurred to me to try again for Draba verna seedpods from
the selection by the curb. I would use the strong light, this time.
*
The Photos
Purshia tridentata,
antelope bitterbrush, Rosaceae family
0110-0196
0120 A small shrub out away from import corner. No other
shrubs near in any direction.
0185 A fury, glandular calyx tube. It looks as though there
is a petal tube inside a sepal tube. It didn’t occur to me to cut one open.
Lomatium triternatum,
9 leaf biscuitroot, Apiaceae family
0210 Lomatium triternatum patch. They are abundant
everywhere in the park and have been for some time.
Malus sp. Rosaceae
family
310-370
310 It didn’t look, from a distance, as if blossoming had
occurred but when I got close I saw that blossoming had come and gone. I
destroyed the best remaining blossom trying to photograph it. I found only two
or three more or less complete blossoms, two inaccessible.
330 the stamen and styles look quite strange.
The ‘furry’ rim is re-curved sepals.
Cornus sericea, red
osier dogwood, Cornaceae family
410-420
I suppose this one is domestic, it seems too dry here. the
others may be domestic, as well even though they are in south pond. There were
once homes near the pond.
Microsteris gracilis,
slender phlox, Polemoniaceae family
510-540
I don’t remember seeing this plant in ‘patches’. I remember
them single, here and there. Something to watch for.
530 Another plant with a corolla tube, a tube of fused
petals. Ben Legler mentions that the base of the tube, below where it flares
into pink lobes is yellow. There is only a hint of the yellow in this photo.
540 It has distinctively opposite, clasping leaves lower on
the stem. Burke’s plant description says the leaves become alternate higher up.
510 and 530 suggest alternate leaves below the blossom.
Burke also says the blossoms occur in pairs. I have
discarded photos that suggest but do not show buds among the alternate leaves
high on the stem. Perhaps they would have been apical on branches, later.
Camassia quamash,
common camas, Liliaceae family
610-630
620 Finally got the image of the three stigmas. The styles
supporting the stigmas will be three styles, fused, leading down to three
chambers of the green capsule. It didn’t occur to me to open the capsule. Maybe
next time.
Unidentified shrub,
import corner [
710-760
720-730 It will be interesting, if I ever get an
identification for this plant, to find out about the strange structure
supporting the fruit.
750 Empty husk.
Lomatium macrocarpum,
bigseed biscuitroot, Apiaceae family
810-840
The shiny metal in some images of umbellule, the subdivision
of the compound umbel [I had to look it up] below are the tips of tweezers.
Draba verna, spring
whitlow grass, Brassicaceae family
910-960
920 That looks like a bulb under the plant. Burke says D.
verna is an annual. I didn’t notice the bulb like structure at the time of the
photo. Another next time.
I am very pleased with 930. It looks like it must have been
exposed in the shade of my body. I was leaning against the hood of my car, in
front, on the side-street beside Skippers. The light outside the shade of my
body was full sun.
*********************************************************************
TRYING TO MAKE SENSE OF SILICLES; some vocabulary
difficulties
The fruit of Draba verna and other members of the
Brassicaceae family is a dehiscent fruit [Dehiscent: It opens on maturity]
called a ‘Silicle’.
Silicle is a dehiscent fruit derived from more than one
carpel.
What the hell is a carpel?
I’ve been confused about this for some time. I need to take
a couple of steps backward.
*
Angiosperms [flowering plants] are not male or female. They
are not ‘sexual’. But apparently as a convenience the botanists refer to male
parts [the androecium] and female parts [the gynoecium].
The gynoecium has been called ‘the pistil’.
It has also been called, ‘a carpel’.
*
The female parts of a flowering plant [an angiosperm] are an
ovary with a style [usually, Draba verna has no style] and a stigma.
If there is only one set ‘female parts’ all three terms
apply. It is the gynoecium, it is a pistil, it is also a carpel.
HOWEVER, there is often more than one set of female parts.
In that case, each set is a carpel. The collected carpels
are the gynoecium or the pistil.
So, it seems that the term pistil, [The familiar term in my
experience] though used widely, is out of date … and is the source of my
confusion.
*
It’s a singular and plural sort of thing, but not really.
The gynoecium, the female parts, may include only one carpel but it might
include more than one carpel.
Why botanists think a Greek word, gynoecium, meaning ‘woman
house’ is more effective than the English phrase, ‘female parts’ is beyond me.
[Ok, it’s the old Lingua Franca thing. But they could pay attention to just who
it is that they are addressing. When they are addressing us, they can use our
language, if they choose to do so. They do not often make that choice.]
*
So much for the names of things.
Getting on with Draba verna and its silicle.
There are plants with only one carpel that has only one
ovary. Its ovary may contain a single ovule that will develop into a single
seed but it may contain two or more ovules that will develop into two or more
seeds, even many seeds.
And there are plants with two or more carpels that may be
partially or totally united. [Are there plants with multiple carpels that are
not united? I don’t know.]
*
The ovary is the swelling at the base of the carpel. The
ovary is a chamber [a locule] containing a single ovule or more than one ovule.
For some reason, a ‘united carpel’ is called a compound
ovary rather than a compound carpel.
The interior walls of the united carpels may or may not
‘breakdown’. If the interior walls breakdown the compound ovary is unilocular
[has a single chamber]. If the walls do not breakdown the ovary is multilocular
[it has more than one chamber]. [Draba verna looks to be multilocular. It seems
to have two chambers. But maybe not.]
After fertilization the ovary wall, protecting an ovule or
multiple ovules, is called ‘the pericarp’. It is now a wall protecting the
fruit.
In fleshy fruits it has three layers, one of which is good
to eat but never-mind that.
In dry fruits, like those of Draba verna, the pericarp tends
to become papery or leathery. If it opens at maturity the fruit is dehiscent
[It opens at maturity]. If it remains closed at maturity and has to rot away or
be digested away, it is indehiscent.
*
There are said to be four kinds of dehiscent fruits. I’m
only interested in one, here, but I will mention the others anyway.
If the plant has only one carpel, the dehiscent fruit is a
follicle or legume. Drumheller
Springs Park
If the plant has multiple carpels the dehiscent fruit is a
capsule or a silique. Lots of the park’s plants have capsules. The Brassicaceae
family, which includes Draba verna, has siliques. There are several other
Brassicaceae family plants in the park.
*
The silique develops from two fused carpels.
It has two parietal placentas.
[Placenta: The point on the ovary wall where the ovule is
attached by a funiculus [Funiculus a stalk attaching the ovule to the
placenta].
[Parietal placentation: a form of placentation in which the
placentae develop along the fused margins of a unilocular [single chambered]
compound ovary.]
This seems to be a place where the botanists cop-out on
their tangled vocabulary.
Parietal placentation refers to unilocular compound ovary, a
compound ovary with one chamber and the silique has two parietal placentas. The
seeds are obviously attached to both sides of the transparent septum at the
point where the fused margins of the compound ovary would have been before
dehiscing [before the ‘valves’ fell away] see photos 930, 940 and 950, May 09,
2013.
So the septum, the wall separating the chambers of the
compound ovary is not a septum, it is a ‘false septum’ because the definition
of parietal placentation requires a single chamber, not two chambers separated
by a ‘wall’ [a septum].
[The paragraph above is wild speculation. I have no idea
what the real reason for calling it a false septum is.]
*
Apparently the ovary of each carpel of Draba verna, each
carpel of its silicle, contains ovules that develop into many seeds, [see,
again, the many seeds in the photos referred to above’.
*
Each ovule is attached by a funiculus [Funiculus: a stalk
attaching the ovule and later the seed to the placenta [Placenta: The point on
the ovary wall where funiculus attach to the ovary wall.]. [See, again, the
photos for the funiculus apparently attaching the seed to the false septum. The
seeds apparently attach to the ‘false septum’ at the point where the valves
apparently enclose the septum. The valves are, of course, missing in these
photos. The have dehisced.]
*
Evolving names: The ovary wall protecting the ovules became
the pericarp protecting the developing seeds. The pericarp now becomes ‘valves’
that will expose the seeds by dehiscing.
*
At maturity differential moisture [more on one side than the
other] and perhaps other mechanisms causes the valves to fall away exposing the
seeds on both sides of the transparent septum.
The seeds fall to the ground.
Great photos as always. Thanks!
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