Sunday, July 10, 2011

Common milkweed and some visitors

Common milkweed, Asclepias syriaca, is my all time favorite wildflower.  The flowers are beautiful, the plant is always teeming with insect life, and different parts of the plant are edible (cooked) in different parts of the season (the spring shoots being my favorite).  What a shame that so many people see it as a weed and pull it out.

The photo of an umbel shows some flowers pink and others already yellowing.  I've noticed that pollinating insects seem to visit only the pink ones.  I don't know if the yellow ones are those that have been pollinated, or those that are withering, whether successfully pollinated or not.  I suspect the latter, since I've read that few flowers in each umbel are successfully pollinated.  I don't know what kind of insect that is on the umbel.

Bumble bees (Megabombus spp.), don't seem as attracted to milkweed as honey bees, but this one rested for quite awhile on that one flower yesterday morning, before flying off.  I don't really have a favorite insect, but Megabombus is definitely my favorite genus name.  Click on the photo and look at those hairs.  Insect hair differs from mammalian hair in composition:  Hair of the former is a polysaccharide called chitin, and that of the latter is a protein called keratin.

The two milkweed beetles, Tetraopes tetraophthamus, are embarking on the well worn path of passion to progeny.  this beetle feeds on milkweed, and advertises its distastefulness with bright coloration like the monarch butterfly, whose larvae also feed on milkweed.

For a spectacular photo tour of the life cycle of common milkweed, see:
http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artfeb05/bjmilkweed.html
The close-ups at that link are amazing.  Also some great info - Hope you check it out

3 comments:

  1. We had five milkweed plants growing near our pond last summer, so when the pods burst I "helped out" by raking some of the seeds into the surrounding soil. We've got about 40 new milkweed plants in bloom at the moment, and the bees and milkweed beetles couldn't be happier. I've only seen one butterfly so far, but I hope to expand our milkweed patch again this autumn.

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  2. Very interesting, Janet. I enjoyed the photo tour. Could the fly in the first picture be a tachinid, bane of the monarch butterfly? I hope not.

    http://www.oocities.org/brisbane_flies/TACHINIDAE.html

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  3. The link didn't work for me, but I just googled tachinids and see that you are probably right. Oh, well, we humans kill and eat billions of beautiful creatures, too.

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