Small-Head Sunflower – Helianthus microcephalus

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Small-Headed Sunflower (Helianthus microcephalus) belong to the Asteraceae family

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Long about the middle of August into September plants of the Aster family begin to take over on my property and along roadsides.  Most of them are tall and bossy.  Invasive. There are several plants of the Helianthus genus in the area.  The name comes from Latin but warmed over from the Greek word for Sun – Helios, and Flower – Anthus. 

Besides reproducing from seeds which are spread by the wind and animals picking them up here and depositing them there, they spread by rhizomes, which are underground runners and thus make colonies.

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The other part of the scientific name also means exactly the same thing in English – something you don’t come across often in trying to match up scientific names and common names.  In botany, the first name alludes to the genus of the plant and the second name, the epithet, most of the time describes the plant.  Micro, of course means small, and cephalus comes to us again, in a rather circuitous way, from the Greek and means head.  In the above picture I am holding up a Woodland sunflower (Helianthus divaricatus) to show how, indeed, the flowers of the Small-Headed Sunflower are, by comparison with other sunflowers, “Small headed”.

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Besides having small flowers, there is another characteristic of the Small-Head Sunflower.  That is, that you will note many flowers growing atop the plant which is anywhere from 3 feet to 7 feet tall.

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 The leaves are opposite and can either have smooth edges or toothed edges.  They are slightly sticky and hairy.

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Sometimes Asters will be refered to as Composite flowers.  That is because what we see as “A Flower” is really composed of ray flowers (the yellow petals in the Small-Headed Sunflower) and the disk flowersIn the slightly out of focus photograph above, notice the many small flowers that compose the Disk.  Soldier beetles (Chaliognathus pensylvanicus) are particularly fond of these flowers and make great photographic subjects as they meticulously go from one tiny disk flower to another extracting its nectar and at the same time, pollinating.  They are posted insects of a win-win situation.

This plant is tall and rather invasive as it spreads with rhizomes so invited into a flower bed one needs to think things through a bit.  They need to be in a contained area as well as being placed where a tall ungainly plant will be an asset. But, indeed, the plants do not balked at being brought into the garden and make a nice show in late summer. They do well in full sun or filtered light and normal soil conditions.  In other words, they are not the prima-donnas of the Mint family who require more moisture than one is sometimes willing to give.

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