The radishes did well this year. Planted in containers on March 29th (in St. Louis, USA), they were harvested one month later. The short, early season means that they’re a workable crop for school. Students can plant, harvest, and consume them all within a semester.
The CDC’s Fruit and Vegetable of the Month website has a little history, some information about the varieties, nutritional information, recipes, and more information about radishes. The University of Illinois Extension also has information about planting and growing.
NutritionData.self.com has some very nice graphical representations of the nutritional value of the food (although their serving size is 1 cup of slices, which seems a bit much).
These sites, however, focus on the radish bulbs, and not on the fact that the leaves are edible. Radish Leaf Pesto is quite good.
Harvested radishes. Both the red bulbs and the green leaves are edible. You'll note that radishes also spot a long tap-root.
Knap-weed or matfelon and cornflower or bluebottle, by Richard Waller (1689) from The Royal Society's Picture Library.
The Royal Society’s Picture Library is now available online. It contains images from some of the seminal scientific works of the last four centuries. It’s an excellent resource for teachers and students, who, with registration, can get free high-resolution images for presentations and unpublished theses.
I’m particularly attracted to the biological drawings at the moment because I’m trying to get students to practice their scientific drawing and diagramming.
Shaw’s website is full of details about his adventures in foraging, as well as a lot of recipes — including some excellent photographs of the work in progress.
I took a half-day trip during spring break (somewhere around the 31st) to the Shaw Nature Reserve in Gray Summit. I was hoping to find some books on native, Missouri, flora and fauna, and see if the Reserve would be a good place for a field trip (they have sleeping facilities so even overnight trips are a possibility).
I found a number of books, including a nice one on mushrooms, and while I could have, I did not pick up one on wildflowers (of which there were several). Of course, spring is the perfect time to see wildflowers, especially since we ended up hiking the Wildflower Trail, so I’m probably going to have to go back sometime soon.
The lady at the main office (where you pay $5/adult) recommended we take the Wildflower Trail and then cut down south to the sandbar on the Meramec River, which is an excellent place for skipping rocks. She also recommended I take my two kids to their outdoor “classroom” for some real, unstructured play.
Without a reference book, I’ve had to resort to the web for identifications, with only a little success, so I’ll post a few of my photographs here and update as I identify them.
The following two pictures are of a flower that was found covering the hillslope meadows; open areas with short grass.
Beautiful reddish-orange blooms on this small herb.This picture better captures the growth form and leaves of this hillslope, meadow flower.A yellow petalled variant.
Like little stars in the daylight, these small, white flowers meadow flowers almost sparkle.
Small, white, meadow flowers.
Pretty, small, yellow, meadow flowers.
Yellow, meadow flowers.
These bent-over flowers can be found on the lower, shadier edges of the hillslope meadows.
These guys like the shadier areas.I love the texture of the charred wooden stump behind the flower. The meadow itself is possibly the result of a burn.
Iris’ were also in bloom.
Small iris.
Another herbaceous, yellow flower.
Pretty yellow flowers.
More, tiny, delicate flowers.
Found in the shadier, moister parts of of the slope.
Once you get under the canopy, you run into some broader leaved plants and their own, interesting flowers.
Bell-shaped flowers in broad-leaved herbs/shrubs.
We ended up spending a lot of time on the sandbar, learning to skip rocks and hunting for clams, but I save that for another post. And we never did get to the play area; that’ll have to wait for the next trip.
Fresh daffodil pollen grains seen under 1000x magnification.
For the record: Daffodil flowers have both male and female parts, which make them good subjects for dissection. And, it’s pretty easy to collect daffodil pollen samples to look at under the microscope. 1000 times magnification seems necessary to be able to make out structures.
Since prehistoric pollen, collected from places like the bottom of lakes, are one of the easiest ways of finding past climates, a study of more recent samples might make for a good student research project in biology or environmental science. They’d need to design the study so they could avoid having to use nasty acids (hydrochloric or hydrofluoric) to concentrate the pollen grains, but that should be possible. Perhaps an ongoing survey using pollen traps, akin to the European Pollen Monitoring Program.
A discussion of the physics of flight, interspersed with birds of prey swooping just centimeters from the tops of your head, made for a captivating presentation on avian aerodynamics by the people at the World Bird Sanctuary that’s just west of St. Louis.
Lift
The presentation started with the forces involved in flight (thrust, lift, drag and gravity). In particular, they focused on lift, talking about the shape of the wings and how airfoils work: the air moves faster over the top of the wind, reducing the air pressure at the top, generating lift.
The shape of a bird's wing, and its angle to the horizontal, generates lift. Image adapted from Wikipedia User:Kraaiennest.
Then we had a demonstration of wings in flight.
Terror from the air.
We met a kestrel, one of the fastest birds, and one of the few birds of prey that can hover.
Kestrel.
Next was a barn owl. They’re getting pretty rare in the mid-continent because we’re losing all the barns.
Barn owl.
Interestingly, barn owls’ excellent night vision comes from very good optics of their eyes, but does not extend into the infrared wavelenghts.
Barn owl in flight.
Finally, we met a vulture, and learned: why they have no feathers on their heads (internal organs, like hearts and livers, are tasty); about their ability to projectile vomit (for defense); and their use of thermal convection for flying.
The ground warms when it absorbs sunlight (e.g. parking lots in summer) and in turn warm the air near the ground. Hot air rises, creating a convection current, or thermal, that the vultures use to gain height.
The Sanctuary does a great presentation, that really worth the visit.
Usually, when new, more powerful predators evolve or come in from elsewhere, the local species can often adapt by themselves becoming better defended through a variety of means [larger sizes, thicker shells for example]; but this option seems to be closed when it comes to the evolution of humans as super-predators.
— Geerat Vermeij (2012), quoted in Walker (2012): Super-predatory humanson the BBC website.
Humans, using ingenuity and tools, have become an uniquely, irresistible predator species that the world has never seen before, and to which other species are finding it very difficult to adapt. That’s the premise of a paper by Geerat Vermeij that’s nicely summarized by Matt Walker on the BBC website.
Normally, predators and prey evolve and adapt to each other. Lions are better able to attack and kill smaller buffalo, which means the larger buffalo are more likely to survive, which results, over time, in the average size of the buffalo herds getting larger.
Humans, on the other hand, like to target the larger buffalo, creating a selective pressure the other way. Unfortunately, once the larger specimens are gone, humans will go after the smaller ones, and the intensity of the attacks have often been enough to drive entire species into extinction.
Though humans have been around for a couple hundred thousand years, we still have not seen our full impact on the environment. Which is somewhat interesting to consider.
