Portraits of Wildflowers

Perspectives on Nature Photography

Posts Tagged ‘prickly pear

Mottled

with 30 comments

As the pads of a prickly pear cactus (Opuntia engelmannii) die, they often become
mottled in ways that are bound to intrigue a nature photograph—or at least this one.

I made these portraits on September 3rd near the Sierra Nevada entrance to Great Hills Park. The overcast skies preceding rain led me to use flash for a change, and that had the advantage of letting me stop down in all three of these pictures to f/14 for good depth of field and crisp details. In the last picture the drying needles and little fruits had fallen from an Ashe juniper tree (Juniperus ashei).

And here’s a thought for today: You’ve probably heard someone say “You can’t prove a negative.” It depends. Some negatives can be proved. For example, take the question of whether a fraction exists such that when you multiply the fraction by itself the result is exactly 2. An infinite number of fractions exist, so you can’t multiply each and every fraction by itself to find out whether the result is ever 2. Maybe you’ll get close: for instance, 99/70 multiplied by itself gives 9801/4900, which is close to 2, but you can see that the top is just slightly more than twice the bottom. It turns out that no fraction has the property that when you multiply it by itself you get exactly 2. Maybe equally surprising is the fact that smart people were able to prove that negative as long ago as ancient Greece. Hats off to the ancient Greeks.

© 2020 Steven Schwartzman

Written by Steve Schwartzman

September 5, 2020 at 4:34 AM

Two tuna takes today, Tuesday

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Tuna is the Aztec-to-Spanish-to English name for the fruit of the prickly pear cactus. Tunas start out green and ripen to various shades of red. Here are two rather abstract takes on Opuntia engelmannii from my neighborhood on August 3rd. In the first, I focused on the tip of an adjacent spine. In the second and much closer view of a different tuna, you see a clump of the short spines called glochids (with the ch pronounced k, as in other words of Greek origin like chasm, stomach, and psychology). Shadows, which are many a photographer’s delight, including mine, play a role in both of these portraits.

Here’s a little-known fact from American history: I certainly wasn’t taught in elementary school, high school, or even college, that before the end of slavery in the United States some free blacks (many actually of mixed race) owned slaves themselves. Hard to believe, isn’t it? And yet it turns out to be true: a thoroughly footnoted 1985 book confirms the practice in one state, South Carolina, via census data, bills of sale, wills, letters, and other documents. It just goes to show that people are people.

© 2020 Steven Schwartzman

Written by Steve Schwartzman

August 18, 2020 at 4:30 AM

Small grasshopper on prickly pear cactus by ripening tuna

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grasshopper-on-prickly-pear-pad-by-tuna-0091

Place: greenbelt along the upper reaches of Bull Creek.

Date: September 12.

Reminder: tuna is the Spanish (and now English) name for the fruit of the prickly pear cactus.

© 2016 Steven Schwartzman

Written by Steve Schwartzman

September 30, 2016 at 5:14 AM

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