Pampas grass, a native of the Andes, is invasive plant number one in Encinitas. It has been planted by some people for its large, showy plumes; however, those plumes produce millions of seeds that are spread by the wind. The grass is an aggressive colonizer that competes and displaces native vegetation and cannot be used by native birds and mammals that are considered pests.
Older clumps of Pampas grass can harbor rats and snakes and be a fire hazard. A group of volunteers is encouraging homeowners to remove any Pampas grass on their property. If the clumps are small, pulling or digging them out is best, especially if the soil is moist. Wear gloves, as the blades are abrasive! Most clumps, however, will be full size and the following is recommended:
1. Carefully cut off seed heads and bag them for disposal as trash
2. Apply glyphosate (aka Roundup) spray to the foliage. The herbicide is taken up by the foliage and transferred to the plant roots. It is safe for humans and pets, and breaks down soon after application.
3. After foliage has died, remove it.
Sanford Shapiro is a certified Master Gardener with the University of California Extension Service and Encinitas Parks and Recreation Commissioner.