Monarch on Milkweed

I got this picture of a Monarch landing on a milkweed (probably Common Milkweed). Although this plant looked pretty young, most milkweeds had blossomed earlier in the summer [1], and I don't see flowers on it. My suspicion is that this is a female looking for a good spot to lay an egg, which will hatch into a milkweed-eating caterpillar.

I'm told that under favorable conditions a Monarch can go from egg to adult butterfly in a little over 25 days:

  • 3-8 days to hatch
  • 3-5 days for each instar X 5 instars = 15-25 days as a caterpillar
  • 8-15 days in chrysalis
  • 26-48 days to become a butterfly
Any egg laid on this day should be a functional adult by either mid-September or very early October. Both these dates most likely mean it would be in the super generation that migrates down to winter in Mexico [2].
August 15, 2021 at Duke Farms
Photo 152591256, (c) jpviolette, some rights reserved (CC BY-NC)

[1] You can see flowering milkweed any time of the summer. If a plant is cut before it goes to seed, it'll usually attempt to start over, flowering again, hoping to be pollinated, and then going on to produce seeds.

[2] I do wonder what happens to Monarch eggs laid late in September. If the weather is warm enough, their offspring might grow into adults and be in the rear guard of their southern migration.

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