A picture of a flower bush where the flower was taken from.
A satellite view of the location in Pasadena, CA where the flower was found. [source: Google maps]
5/8/19 4:30pm plucked a flower from the south west corner of Caltech’s campus. Prepared sample by rubbing the center of the flower on a slide then taping on a cover slide (on the sides). The flower was yellow with red and the center and serrated edges, and it was about 2 inches across.
A close up of the flower I used.
I identified the flower to be a Coreopsis grandiflora of the family Asteraceae, also called a large-flowered tickseed. it is also referred to with the names Baby Sun, Sun Kiss, Early Sunrise, or Sun Ray. The image I took looks almost identical to the image below.
A picture of Coreopsis grandiflora [source:
https://www.waltersgardens.com/variety.php?ID=CORKI ].
I took a few images of the pollen with my foldscope and my phone camera (Samsung Note 9). The pollen is small, yellow, and circular and found in clusters. A few larger pieces of other plant material and some yellow looking liquid can also be seen. I also took some close up photos using the optical zoom on my phone. In these, you can see the spherical spiked structure of the pollen

A 140x foldscope image. There are many small yellow circles.

The foldscope lens is 140x magnification. Based on other foldscope images, this pollen is probably on the order of magnitude of about 10 – 30 microns. How to get more pollen on to the slide? The pollen was difficult to find. Maybe there is some way to dissect the flower.
#caltechbi1