Hydrocotyle moschata

This is another very specialized post that will only be of interest to a very small number of people. However, I hope that it might help those that are interested in such things to identify this plant.

A couple years ago an attractive little ground cover showed up in my garden in Oakland, in among the Mazus reptans that I had planted. I knew that anything that shows up on its own is probably a weed, but, it was very attractive, didn’t appear to be moving very fast, and didn’t seem to throw seeds. So, I left it until I could find out what it was.

I took samples of the plant to a number of local nurseries, but no one was able to ID it. They all asked what the flower was like, but, as far as I knew I had never seen it in bloom. Well, this year I caught it flowering (the flowers are almost microscopic), and I identified the plant (though not from its inflorescence.) It is Hydrocotyle moschata, a somewhat invasive non-native from New Zealand. Here are some useful links for further info:

• Calfora Taxon Report 4280
• New Zealand Plant Conservation Network

The following are photos of the plant, its leaves, stolons, and of the inflorescence taken using a microscope at 40x. I hope this is useful for someone.

Hydrocotyle moschata sprigs showing leaves, flowers, and stolons

Hydrocotyle moschata sprig with flower head

Hydrocotyle moschata flower under microscope at 40x

Hydrocotyle moschata flower under microscope at 40x (another view)