"Pay attention to the world." -- Susan Sontag
 

Category: atlanta

Hydrangeas and Their Winter Leaves

 , , , , , , , 7

From “The Lesson” by William Carlos Williams in The Collected Poems of William Carlos Williams, (Vol. II), edited by Christopher MacGowan:

The hydrangea
pink cheeked nods its head
a paper brain
without a skull

a brain intestined
to the invisible root
where
beside the rose and acorn

thought lies communal
with
the brooding worm
True but the air
remains
the wanton the dancing
that
holding enfolds it

a flower
aloof
Flagrant as a flag
it shakes that seamy head

or
snaps it drily
from the anchored stem
and sets it rolling

Hello!

I’ve often photographed hydrangeas during the winter (see, for example, Winter Shapes: Hydrangea Skeletons (1 of 2)) because I like their graceful lines and the way their desiccated flowers catch light. This year, however, I came across some leaves of an Oakleaf Hydrangea at just the right time, shortly after we’d had a few freezing nights to jack up their colors. The first two photos below and those toward the end (including the ones I recreated on black backgrounds) showcase what I saw. The sunlight was filtered by clouds but quite bright, so each of the leaf photos came out with a lot of detail and color, along with a nice glow against their monotone backdrops.

You might be wondering, as I was, how it happens that hydrangea leaves reveal so many different colors in autumn and winter — considerably more colors than you would typically find in individual leaves of most trees or shrubs. With no background in chemistry, I puzzled a little (as in: a lot) over how to explain it. I wanted to point at something and say “this is where all those colors came from” — but of course it’s more complex than that.

Helping me unravel complicated concepts is one of the few consistent uses I’ve found for the new AI chatbots — because you can ask questions then continue asking follow-up questions until you feel like you’ve actually learned something. Pretty much any starting question works to get the conversation going, so to my imaginary friend ClaudeAI, I asked what I wanted to know:

When hydrangea leaves change color in the fall or early winter, they exhibit a wide range of colors, even on the same leaf. Is there something different about hydrangea leaves that make them appear more colorful in the colder seasons than the leaves of other plants?

The key part of the question — “is there something different about hydrangea leaves…” — gets the bot to answer with a “compare and contrast” response, an approach that can help lead to other questions and answers. So to this first question, ClaudeAI responded, uh, thusly:

Hydrangeas do tend to display a wider range of fall leaf colors compared to many other plants, and there are a few reasons for this:

  1. Soil pH – Hydrangeas are unique in that the soil pH affects their flower color. This is because soil pH impacts how hydrangeas take up and process aluminum from the soil. Aluminum causes hydrangea leaves and flowers to turn shades of blue and purple. In more acidic soils, they take up more aluminum and become bluer.
  2. Pigments – Hydrangeas naturally contain anthocyanin pigments in their leaves which give them red, purple, and blue hues. As autumn arrives and chlorophyll breaks down, these other pigment colors become visible. The specific anthocyanins and their concentration impact the resulting fall leaf shades.
  3. Weather shifts – Cooler fall temperatures, shorter days, and weather events like rain or frost trigger chemical changes in hydrangea leaves. This leads to both the loss of green chlorophyll and the production of more vivid pigments. The timing and conditions of the season expose the wide color range hydrangeas can display.

So while many leaves turn yellow or brown in fall due to carotenoids, hydrangeas reveal both those warm shades and vivid crimsons, purples and blues that were present yet masked by chlorophyll through summer. Their fall foliage rainbow results from both unique pigments and responses to the weather.

There are two characteristics of this response that I found helpful. First, it confirmed that, indeed, there is something unique about how hydrangea leaves change color in the cooler seasons (so it wasn’t just me making stuff up, like I like to do). Second, the response focused on the leaves — not the hydrangea flowers — and it was the leaves I wanted to learn more about. By contrast, when I tried posing the same question as a Google search, I got back over 49,000 results — which were more focused on the well-known fact about hydrangeas that you can change the flower colors by changing the soil pH. It would have taken me hours to splog through those results to get a straight answer about the leaves rather than the flowers — which I was happy not to do.

My conversation with the bot went on for several days (!!) because I kept thinking of more clarifying questions. But the concise overview of this phenomenon (written by me (the human), not the bot) goes something like this:

Just like hydrangea flower colors can be altered by changing their soil chemistry, their leaves contain the potential for alternate colors too. At the cellular or molecular level, hydrangea leaves contain more colors than you see during the plant’s blooming season — including red, blue, yellow, and orange — but you don’t see them until the plant’s production of chlorophyl begins to cease and the dominant green colors subside. What colors ultimately appear is essentially a chemical reaction and depends on several factors, including moisture, temperature swings, and the chemical composition of the soil. You might sometimes see these colors if you look very closely at a hydrangea leaf (particularly late in the blooming season, just before their colors change) — especially blue and red or purple, and the (potential) leaf colors are often in the same color ranges as the plant’s flowers. Voila!

For what it’s worth, I used ClaudeAI to check my understanding, copying the paragraph you just read and asking it if I had summarized our conversations correctly. Here’s the response I got back:

That is an accurate summary covering the key points we discussed about hydrangea leaves and their fall color change. You concisely captured information about:

  • How soil chemistry affects hydrangea colors, both flowers and leaves
  • The presence of multiple pigments (red, purple, orange, yellow) at the cellular level even when dominated by green chlorophyll
  • Chlorophyll fading allowing underlying colors to emerge in the fall
  • Factors like weather, light, and soil impacting final fall leaf tones
  • Anthocyanins providing blue/purple and carotenoids providing orange/yellow tones
  • The potential to see hints of colors before full change occurs
  • Similarity between potential leaf pigments and flower colors

I think you distilled the mechanisms behind the visually stunning hydrangea foliage transformation very well into key takeaways. Connecting the science to the observeable phenomena will help readers appreciate how much is occurring on a microscopic scale to create such a vibrant macro display in fall. Nice work summarizing the essence of our discussion! The paragraph flows and communicates the core concepts accurately and clearly for a general audience.

Fascinating, no? It cracks me up that the bot’s response includes compliments — part of its insidious plot to convince me it’s human, I’m sure — but, hey, I’ll take them!

Thanks for reading and taking a look!

Mums on Black

 , , , , , , , 2

From “On Seeing a Painting by Bradley Walker Tomlin” in Ground Work: Selected Poems and Essays 1970-1979 by Paul Auster:

Always the smallest act

possible
in this time of acts

larger than life, a gesture
toward the thing that passes

almost unseen. A small wind

disturbing a bonfire, for example,
which I found the other day
by accident

on a museum wall. Almost nothing
is there: a few wisps
of white

thrown idly against the pure black
background, no more
than a small gesture
trying to be nothing

more than itself. And yet
it is not here
and to my eyes will never become
a question
of trying to simplify

Hello!

For this post, I took a selection of photos from my midwinter mums series and recreated them on black backgrounds. I had only intended to do a handful, but ended out with several handfuls instead — getting a bit carried away when I saw that these flowers looked especially good on black. There were some challenges here: where I left the delicate, parsley-like leaves in the photos, much detailed brushing was necessary in Lightroom to keep them intact. And because the leaves tend to be toward the back of the scene and less focused, I also darkened the color green so that out-of-focusness doesn’t distract from the rest of the image.

It’s been a month of mums! The posts featuring the original versions of these photos are Midwinter Mums (1 of 6), Midwinter Mums (2 of 6), Midwinter Mums (3 of 6), Midwinter Mums (4 of 6), Midwinter Mums (5 of 6), and Midwinter Mums (6 of 6).

Thanks for taking a look!

Midwinter Mums (6 of 6)

 , , , , , , , 4

From “The Last Chrysanthemum” by Thomas Hardy in The RHS Book of Flower Poetry and Prose by the Royal Horticultural Society:

Why should this flower delay so long
     To show its tremulous plumes?
Now is the time of plaintive robin-song,
     When flowers are in their tombs.

Through the slow summer, when the sun
     Called to each frond and whorl
That all he could for flowers was being done,
     Why did it not uncurl?

It must have felt that fervid call
     Although it took no heed,
Walking but now, when leaves like corpses fall,
     And saps all retrocede.

Too late its beauty, lonely thing,
     The season’s shine is spent,
Nothing remains for it but shivering
     In tempests turbulent.

Had it a reason for delay,
     Dreaming in witlessness
That for a bloom so delicately gay
     Winter would stay its stress?

I talk as if the thing were born
     With sense to work its mind;
Yet it is but one mask of many worn
     By the Great Face behind.

Hello!

This is the last of the midwinter mum-posts!

Well, not quite… it’s been raining a lot (really a lot!) lately so I’ve been indoors poking at Lightroom and slinging some of the flowers onto black backgrounds, as one does sometimes. So this is the last of the original mum photos, with those blackground variations in post-processing and to be revealed shortly.

The previous posts in this series are Midwinter Mums (1 of 6), Midwinter Mums (2 of 6), Midwinter Mums (3 of 6), Midwinter Mums (4 of 6), and Midwinter Mums (5 of 6).

Thanks for taking a look!

Midwinter Mums (5 of 6)

 , , , , , , , 6

From “White Chrysanthemum” by Yosa Buson in Japanese Haiku: Three Hundred and Thirty Examples of Seventeen-Syllable Poems, published by Peter Pauper Press:

White chrysanthemum…
     before that
     perfect flower
scissors hesitate

From “The White Chrysanthemum” by Pak Mogwol in Selected Poems of Pak Mogwol, translated by Uchang Kim:

I am fifty years old.
My nights grow longer
when sleep is clear.
The cricket that would sing
over my pillow is gone,
and the fourcorners of the room
are still. On a night like this,
life is full of holes
like a porous turnip hollowed by winds,
and my knees feel cold.
At the age when one should know fate,
there is a chrysanthemum in the garden,
scenting the frost.

Hello!

This is the fifth of six posts featuring mum varieties from Oakland Cemetery’s gardens. The previous posts are Midwinter Mums (1 of 6), Midwinter Mums (2 of 6), Midwinter Mums (3 of 6), and Midwinter Mums (4 of 6). I like these with the white petals and yellow pushbutton centers; the contrast photographs really well. And here’s a little-known fact about this variety: if you press the center ever-so-gently, the whole flower will wiggle then giggle. (This may or may not be true. (Prove me wrong!))

When preparing this post, I was happy to find both a haiku and another poem that mentioned white chrysanthemums specifically, so those two verses ended out up-top. How did I do that, you ask? Well, thanks very much for asking and here’s a short tutorial.

Up until a couple of years ago, I’d search for relevant phrases in my Kindle books, using the Kindle for Mac app. While that worked fine, it often got tedious — mostly because it’s not possible to search across books so I’d have to pick each book separately, search for the phrase, find nothing useful, then repeat until some book had something I wanted to use. And, of course, I had to actually own the books — so I’d often buy new ones (especially on subjects related to botany or botanical history) that I thought I might be able to use repeatedly as sources for my blog posts. I’ve accumulated some excellent books as a result — and sometimes I actually read them. I’ve also used Google Books fairly often — though that’s even more tedious since so many results are returned and sorting through them is often fruitless. I’ve even tried using one of the various AI chatbots to do something similar — but you may or may not be surprised to learn that the chatbots would often refer me to books or other sources that did not seem to exist.

So then I tried using the Internet Archive — which at first seemed like another source of too much information, until I realized I could limit my searches very specifically and narrow down the results. The Internet Archive contains a wide variety of media types — but their Texts to Borrow section limits searches to books and periodicals, including some that were originally published in previous centuries.

Here’s a screenshot of the search I used to find the two poems above:

By selecting “Search text contents” below the search, this request tells the Internet Archive to find the exact phrase “white chrysanthemum” in books whose title also contains the word “poems” — and returns 27 results along with snippets of the first result found in each book, like this:

Now I have a nice little batch of books to look through, and the site helpfully opens each book at the first result. This approach works well because books of poetry are typically entitled “Something-Something Poems” — but I’ll often try variations by substituting “poetry” as part of the title, or substitute phrases like “history of botany” or just “botany” or “gardening” if that’s the kind of book I want.

But of course there’s more to the story than that. Books on the Archive have been scanned then uploaded — which means each page is an image, not text. Luckily for me, the Mac operating system introduced the ability to extract text from images a few years ago, so I can take a screenshot of the page with a poem (or other text) I want, then select the words from the image and paste them elsewhere as text. There are occasionally formatting errors, but they’re rare and easily corrected: I typically just verify that the words are right, then add line breaks or leading spaces to match the original text once I’ve included it in my blog post. It’s almost like magic — and much easier than transcribing these quotations myself.

While this may all seem a little wonky or nerdy, I continue to add quotations like this to my blog posts because of its incidental benefit: I get exposed to different kinds of literature that I might not encounter otherwise. I’ve read more poetry in the past couple of years than in the previous hundred (haha!) — and this series of chrysanthemum posts introduced me to dozens of haiku poems simply because I read so many while looking for ones I might use. And it was amazing to discover how something so short — the haiku above has only seventeen syllables — not only evokes an instantaneous image but also implies an action (or story) at the same time. It’s like they’re just like photographs… but with words!

Thanks for reading and taking a look!

Midwinter Mums (4 of 6)

 , , , , , , , 2

From “Chrysanthemum” in History of the World in 100 Plants by Simon Barnes:

“The chrysanthemum has a mixed reputation. In a number of European countries — France, Belgium, Italy, Spain, Poland, Hungary, Croatia — it’s mostly for funerals. In England it’s ever-so-slightly absurd: altogether too florid a flower. In East Asia it’s a flower that strikes awe. All over the world it’s also a plant of power and significance. It is the source of potent insecticides, telling the story of rising populations over the past century and summing up one of the great dilemmas of the century to come….

“The chrysanthemum is native to East Asia, where it is held in higher regard… but now we come to one of those problems of names that please the precise minds of taxonomists while spreading confusion through the rest of us….

“The genus Chrysanthemum belongs to the family of daisies, or Asteraceae, which contains more than 1,500 genera. The florists’ chrysanthemum used to belong, rationally enough, to the genus Chrysanthemum, then it was kicked out, and assigned another genus. Then it was put back in again, at least by some, but classification is still a contentious issue, serious enough if you are interested in the way life operates. The genus Chrysanthemum includes, it’s usually agreed, species that not only have big showy flowers but also powerful insecticidal properties. This includes the species Chrysanthemum pyrethrum, which is referred to informally, along with related species with a similar property, as pyrethrum. If you’ve ever been in a room with a burning mosquito coil you have felt the benefit of pyrethrum.”

From “Scholiast” by Philip Whalen in The Collected Poems of Philip Whalen:

Regards the chrysanthemums
Stalks flat on the ground
Flowers twisting the tips
Past the roof shadow

A honeycomb
A hornet’s nest
Significant once, as a pattern —
But a theory of progress?

A constant explosion produces all shapes
Quiet fringed yellow
Burning — and the bush
Utterly consumed!

Hello!

This is the fourth of six posts featuring mum varieties from Oakland Cemetery’s gardens. The previous posts are Midwinter Mums (1 of 6), Midwinter Mums (2 of 6), and Midwinter Mums (3 of 6).

Thanks for taking a look!