New and long-gone plants popping up at Presidio

A surprising outburst of flowering plants in the Presidio has delighted biologists working to restore the park’s legendary Mountain Lake and its surroundings.

The lake’s East Arm was once a patch of dry land with dense masses of wild vines and matted weeds, but this winter’s abundant rainfall, coupled with a rise in the level of the aquifer underground, have nourished the area, ecologists say.

Stringer acknowledged that some of the plants may have appeared because migratory birds carried in their seeds.



[...] the only remaining native population of the plant was growing at Oso Flaco Lake, in Oceano Dunes State Vehicular Recreation Area in San Luis Obispo County.

The new wetland, he said, is rapidly filling with other unexpected flowering plants: grand redstems (Ammania robusta), burheads (Echinodorus berteroi) and giant arrowheads (Sagittaria montevidensis).

A single great blue heron, plus several blue-winged teal, have been spotted flying over the shallow water, and more wild birds are expected, drawn to the area by the new vegetation.

The East Arm is visible through a chain-link fence along Mountain Lake Trail off of West Pacific Avenue,between the Presidio and San Francisco’s Inner Richmond District.