Ambrosia psilostachya - Western ragweed

Western ragweed (Ambrosia psilostachya) is a weedy, rhizome-spreading perennial native to dry fields and disturbed ground across California, generally not recommended for gardens and treated as an indicator of a disturbed site.¹ It grows 0.2-1 m tall and 0.3-1 m wide.¹

Inputs

• Hardiness zone 6¹
• Hardiness zone 7¹
• Hardiness zone 8¹
• Hardiness zone 9¹
• Hardiness zone 10¹

Type

• Herb¹
• Perennial¹

Functions

• Fire resistance²

Dimension	At maturity
Height (m)	0.2-1
Diameter (m)	0.3-1

Footnotes

1. Ambrosia psilostachya, Western Ragweed | Las Pilitas Nursery Native Plant Database ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

2. Leaf burn times of California native plants, Las Pilitas Nursery, 2005 propane-torch ignition trial, live-leaf ignition time >60 seconds ↩