Photo of the Week – October 19, 2018

Dotted gayfeather (Liatris punctata) seeds at our family prairie last weekend.

This is the season of flying fluffy seeds.  Asters, thistles, blazing stars, milkweeds, and other late season flowers are sending their seeds into the air, a few of which might actually land in a place where they can germinate.  Each of those seeds is attached to a filamentous structure, variously called a pappus or coma, depending upon the species of plant.  Those fluffy structures catch the wind and allow the seed to travel many miles, in some cases – though most land within a few meters of their origin.

Seeds that can float on the air are a nice adaptation for plants, but they are also attractive photographic subjects.  Over the last week, I’ve photographed the seeds of common milkweed (Asclepias syriaca), dotted gayfeather (Liatris punctata) and tall thistle (Cirsium altissimum) in some local prairies.  Here are a few of those photos for your Friday enjoyment.

Common milkweed seeds lined up inside their pod, nearly ready for launch.
A common milkweed seed temporarily hung up on big bluestem.
The coma of this milkweed seed got stuck and was drifting lazily in the breeze, having become separated from its seed.
Tall thistle seeds.  Many of these get eaten by insects before they get a chance to fly away, but at least one of these managed to escape – so far.
Dotted gayfeather seeds, backlit by the autumn sun.

Photo of the Week – October 20, 2017

I’ve written before about the value of native thistles, both to pollinators and other parts of prairie ecosystems.  Tall thistle (Cirsium altissimum), in particular, seems to be a key food resource for pollinators during the late growing season, including the migration period for monarch butterflies.  Here in the Platte River Prairies, we include native thistles in our seed mixes for prairie restoration work and try to promote them through our management activities.  Here are some photos of tall thistle from last month.

This bee was one of many feeding from tall thistles this fall.

Skippers like this one often feed from thistles, but this one was just resting on top of a half-empty seed head.

While bees get great value from tall thistles, this one got trapped and killed by the sticky substance on the bracts beneath the flowers (which is probably meant to capture nectar-stealing ants).

Tall thistle seed.

More tall thistle seeds.

Isn’t it a little late to be nesting?

As you might remember, my Photo of the Week last week was an image of a fledgling meadowlark I’d found in mid-September.  At the time, I’d talked about how surprised I was to see such a young bird so late in the season.  Well, last Friday, Eliza Perry, one of our Hubbard Fellows, called me to say she’d just found a nest full of tiny birds – did I want to come take a look?  Of course I did.

American goldfinch chicks sit in a nest about three feet off the ground in a tall thistle (Cirsium altissimum) plant.  Platte River Prairies, Nebraska.
American goldfinch chicks sit in a nest about three feet off the ground in a tall thistle (Cirsium altissimum) plant. Platte River Prairies, Nebraska.

I’m pretty sure what Eliza found was an American goldfinch nest.  The bills and markings on the birds look right, and we spotted an adult goldfinch nearby.  However, the best supporting evidence was that the nest was located in a thistle plant (a native thistle species, by the way) and had thistle down in the nest cup.  There is a strong tie between American goldfinches and thistles.  Unlike most other bird species which feed their young on insects, goldfinches instead feed them regurgitated seeds – especially those of thistle plants.  In fact, they often delay their nesting until those thistle seeds have ripened.  Here is a link to photographer/naturalist Stan Tekiela’s post on this topic, if you’re interested in learning more about the topic.

These birds are even further behind the meadowlark in their development, and it’s already getting pretty cold overnight, so the nestlings’ chances for survival might seem slim.  Of course, the difference between the meadowlark and the goldfinches is that the goldfinches have adults around to help them.  Both have a challenging fall and winter ahead of them, but nothing others of their species haven’t dealt with countless times before, I guess.

A better view of the nest placement within the tall thistle plant.
A better view of the nest placement within the tall thistle plant.

Thanks to Anne Stine, our other Hubbard Fellow, who graciously helped hold equipment for me as we photographed the nest.  Because of the very bright early afternoon sun, I had Anne hold a diffuser near the nest to reduce the harshness of the sunlight while I held a small flash unit to better illuminate the birds.  We worked quickly and got out of the way so the parents could resume their feeding duties.