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5/7/2019, 6pm: Millikan pond rose garden, Caltech, Pasadena, CA

These foldscope photos are of rose flower pollen obtained from the stamen of one flower (the bright pink/orange one in the close-up). A slide was prepared by shaking the stamen so that its yellow, powdery pollen fell on the slide, wetting the slide with a drop of water, and finishing with a cover slip.

The two distinct pollens in the images actually are aggregates of many small pollen grains, which suggests that the sticky, yellow pollen of roses likes to clump. It is possible that this cohesion between grains increases the probability of several pollens being transported at a time by some force like the wind, or pollinating insects, so that there are better chances of pollination. The actual shape of the pollens themselves is spherical to oblate.

I identified the variety of rose as a hybrid tea rose of the genus Rosa due to its tall height around .75 meters (a 2 m tall friend is in the background), the petal-enclosed stamen and pistil, and its individual rose buds on each stems. According to the web, these features are in contrast to most other roses that either have multiple buds per stem, are shorter in height, or have a much wider flower. Apparently, the hybrid tea cultivar was first developed as a hybrid between the hybrid perpetual cultivar and the tea rose cultivar

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