[fosc] scary invasive parasitic plant -- on the edge of our watershed

Karen Paulsell kpaulsell at pacbell.net
Fri Sep 8 16:11:19 PDT 2006

A very invasive parasitic plant has recently been discovered in the 
Bay Area by creek activist Susan Schwartz.  We haven't seen it in our 
watershed -- but it's right on the edge! Just half a block away. 
Susan did a lot of advocacy work when she found the plant, and has 
inspected the site and confirmed the ID.

The plant is Japanese dodder (Cuscuta japonica). It's a really weird 
plant -- no chlorophyll, so it is totally parasitic. It's different 
from our native dodders -- bright yellow (sometimes with red or 
purple splotches) and much bigger, so it's able to climb 
trees.  Experts suspect that birds use the stringy plant material 
during nesting season. Any bits of dodder that come into contact with 
a host plant are able to grow and spread. (It doesn't seem to be 
known whether it blooms and produces by seed here, or not.)

The location is at the east end if Inyo Avenue off East 27th Street. 
It is on the grounds of the Salem Lutheran Home and also 2 or 3 
residential yards. Yes, just 4 blocks from Sausal Creek, and our 
restoration site at Barry Place.  There's a small oak in an Inyo 
Avenue back yard that looks like a bale of straw was dropped on top! 
Other trees have been cut, but the infestation is coming back.

According to a fellow from the state Agriculture department, they 
have a list of several sites in Oakland. But they don't do anything 
about them, citing lack of funding. Contra Costa County immediately 
attacked the infestation she discovered and reported. This is very 
scary, because the state Agriculture website tells property owners 
not to try to manage the infestation themselves, to notify the 
authorites. The residents on Inyo Avenue and the Salem Lutheran Home 
have tried somewhat to control it, but have not succeeded. And part 
of  the infestation is at sidewalk level -- the stuff looks like 
Silly String, I can imagine kids playing with pieces, dropping them 
in other places, decorating other plants with them.

So, FoSC has written  a letter to the Ag Department, urging prompt action.

You can help by being alert for infestations of this plant. There are 
reported other infestations near the Salem site. Take a look at the 
info below for identification information. Note that there is a 
native dodder, but it's much smaller, and orange, not yellow.

Dodder Information online:

Cal-IPC featured dodder on the cover of its summer '06 newsletter: 

California Dept. of Food and Agriculture information page:
(There's a link to some scary photos!)

Some photos of the local infestation are in the "Dodder" album at:


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