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This plant has been growing in the same location on the 18-Acre Elysian Park Parcel since, at least, the late 1990s. It is the only one I've seen in my exploration of vacant parcels in the neighborhood. It's about 4-6" tall, in a patch about 6' in diameter. The spiky filaments on every part of the plant would discourage grazing animals.
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It grows at the base of the northernmost slope, on the first plateau up from Riverside Drive. According to Figure 2.5 (page 9) on plans posted on Rec & Parks' website, it appears to grow in the path of the berm they plan to build for a bioswale. The plant does not appear to have been mentioned in the environmental review for the park improvements: Chapter 3, also posted on Rec & Parks' Website.
Deadline for public comment:
3PM, Monday, October 19, 2009.
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If it is a rare native plant, then we need to ensure Rec & Parks includes it in the environmental review. If you can help identify this plant, please send us an email: redcarproperty@gmail.com. Turkish Rugging was suggested. Looking at CalFlora, we're still looking for an ID.
*UPDATE March 9, 2010. Plant ID via CalFlora: Dove Weed (Croton setigerus), a native plant.