# San Diego Area - wild plant - ID???



## seawulf (May 18, 2010)

I picked these out of a quiet backwater section of the San Diego River in Santee, near San Diego. 

Years ago, this area was clogged with huge water hyacinths. But, now they have been overcome and totally replaced by this plant. It seems to be rooted in the shallows and is just clogging the area like the hyacinths used to. All along their stem, they grow clumps of roots - in the water and they grow just fine as 'floaters'. 

I now have a bunch in my 500 gal fish pond. Although I did not see any of the small yellow flowers in the backwater, they are blooming in my pond. The flowers have 5 petals and are about 1 1/2 inches in diameter. The larger leaves are about 2-3 inches long.

Some research on my part indicates that this may be "Water Primrose" - Ludwigia spp.

These things grow like weeds. You can strip all of the leaves off a stem and within a day or so, new leaves will sprout.

BTW, the barely visible black grid in the pics is bird netting. After never having a problem with bird predation in my pond, I recently came out of the house to find a huge Blue Heron flying out of the pond.

Can anyone help with the plant ID?
Thanks,
CW


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## Seattle_Aquarist (Mar 7, 2008)

Hi seawulf,

Welcome to APC! I saw your post yesterday, I am sorry no one responded. Cavan is our resident plant expert, hopefully he will spot your post this time.

Good pictured of emersed (above water) growth but I don't see any leaves that look like they were submerged. Were there any submerged leaves on these plants and did you get any pictures?

Glad you joined us!


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## Diana K (Dec 20, 2007)

Looks like what the local pond store sells as Water Primrose. IDK the botanical name.


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## Cavan Allen (Jul 22, 2004)

_Ludwigia hexapetala_. It's an invasive species from South America. It's one that's probably not a good idea to spread around.


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## Cavan Allen (Jul 22, 2004)

More here:
http://www.ars.usda.gov/Research/docs.htm?docid=15083&page=3&pf=1&cg_id=0


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## seawulf (May 18, 2010)

Thanks to all for your help.








Roy,
There are no submerged leaves, to speak of. Just some that, because of growth, wind up partially submerged. It appear that these survive for a while, but eventually turn yellow or brown and fall off. The yellow leaves in the attached pics are submerged.

The pic with my hand in it for scale, was an end piece that I inadvertently pulled off about a week ago. Notice the long runners which appeared during this time and the brownish leaves. I just threw the end piece into a bucket of water and this was the result. The brownish leaves were underwater during this period and are failing.

I can see how this thing could be really dangerous to waterways. It's interesting, though that Diana K sees it for sale at local pond stores. I suppose water hyacinths are in the same class of annoying/dangerous aquatic plants. But, they are for sale everywhere around the San Diego area. But, I notice they are NOT shipped interstate around the country. They sell for $3 to $4 each, locally at pond stores. That's why I went hunting for some local plant. I am trying to get my pond shaded to control string algae. Turns out, it's not so local, after all.

Thanks, again to all.

Charlie


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## Cavan Allen (Jul 22, 2004)

I think the plant Diana may be seeing is _Ludwigia peploides_, which is a native US plant and looks superficially similar.


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