This pollen is from a yellow flower from a tree in Ruddock courtyard in the California Institute of Technology, in Pasadena CA (since found on college campus, may or may not be native to Southern CA). The pollen was collected at 3:00 pm on 5/4/19. To prepare the sample, I removed a petal from a flower and stuck the base to a sticky coverslip and then removed the petal, depositing pollen onto the cover slip. I then covered the pollen with another sticky cover slip before imaging.
The plant from which the flower sample was obtained.
Close up of flower, help with species identification would be welcome.
Foldscope magnification: 140x
Pollen size in image: 3 mm
Actual pollen size: 21 micrometers
Some questions: Why do some of the pollen grains appear to have a divot in the center? How many grains of pollen does one flower contain?
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