GWEN IFILL: For those stations not taking a pledge break, we have the story of a plant native to California that scientists thought had disappeared. The report was produced by KQED San Francisco and is narrated by botanist Don Mahoney.
DON MAHONEY, San Francisco Botanical Garden Society: The Franciscana Manzanita has always been somewhat of a mystery. It went extinct in the wild. Finding a plant has always been a holy grail.
We're in the southern edge of Golden Gate Park, in the California native garden in the San Francisco Botanical Garden.
Manzanitas are the iconic plant of California. There are probably roughly 50 species of manzanitas in California. In the rest of the world, there are probably only two or three species. So California is the hot bed of manzanitas.
We have them growing from -- on the beach all the way to the High Sierra.
In Spanish, manzanita means "little apple." And just like apples, they're quite edible.
Manzanitas come in all sizes and shapes and we have lots of them here. The manzanita produces these beautiful little white bell shaped flowers. Before there were garden plants and there were only wild plants, bumblebees used manzanitas in the wintertime.
The bark can be very peely and shiny and almost a cinnamon coppery color.
Two species of manzanita grow only in San Francisco, so they're very rare. One of them is even named Franciscana.
The Franciscana manzanita is a low-growing shrub. It is very adapted to our fog zone. Most manzanitas grow in areas where it's very hot and dry and they really won't grow well in San Francisco. This one loves San Francisco. This one is particularly happy and I think it's happy with its friends at serpentine rock, which is right here. Here it is just kind of creeping slowly over the rock, as if it was a slow moving waterfall. Geologists have identified a special kind of rock with occurs in earthquake fault zones and there's a lot of this serpentine in San Francisco. And it's toxic to most plants. This manzanita thrives on serpentine.
San Francisco has not been kind to its native plants until recent years. Arctostaphylos franciscana grew on some very valuable real estate. As San Francisco developed and became more and more urbanized, it became apparent that this land was going to be developed for housing. The Franciscana manzanita was never really plentiful. It grew only in San Francisco and only on serpentine.
Luckily, those were areas where they had decided to put cemeteries and they left a lot of the natural vegetation around the edges of the cemeteries.
And so it continued to exist until they decided to move the cemeteries. And at that time, they brought bulldozers in, and there went the last of the Archtistaphulus Franciscana.
The final destruction occurred in 1940. A few botanists, with a lot of forethought, salvaged propagation material from these plants and took it to botanical gardens and it was saved.
As far as our records show, all of them were collected from Laurel Hill Cemetery, where Laurel Heights is now.
In -- in October of 2009, Doyle Drive began its construction project. Just south of the toll plaza, within several hundred meters of the south end of the Golden Gate Bridge on a serpentine outcropping.
A lot of vegetation was cleared. This exposed a wonderful plant which was noticed by a young botanist.
This was the -- considered extinct Franciscana manzanita in the middle of a billion dollar construction project.
The Franciscana manzanita was moved about a mile to a new spot in the Presidio. For its own protection, it's best if that location is kept secret.
I look at the remaining natural habitats as the original skin of the Earth. And there's very little of that left in San Francisco. And to actually find one of the anchor and key plants that originally existed in San Francisco and to be able to save it meant a lot to anybody who works with plants and the environment.
As they prepared the plant for moving, they had to clip off some of the edges. All that material was given to five different botanical institutions to propagate from cuttings. When the Presidio material arrived, it looked much like little branches of this. And what we had to do was sort through it and find almost every living green stem like this.
Once the cuttings were made, they were put in a plastic house in indirect sun. Once they have roots, you move them into the soil they're going to grow in from that point on.
It feels really good to see these growing. They're big enough that they're ready to move up to the next sized pot. We had excellent success. We had probably an 80 or 90 percent success rate.
We now have 169 plants potted up with their own roots, looking strong and happy.
There are suitable spots in the Bay Area that have serpentine that are on public property where we could plant these plants out. And that's actively being pursued. The ultimate goal is to establish breeding populations in the wild, so you pretty much need to have genes coming from different members of the population.
Well, since the Doyle Drive is just one member of that population, it's wonderful we have these former Laurel Hill members that have been saved in botanical gardens, because now we do have different members of the population. They can be planted next to each other. They can happily cross. And that will give rise to a viable wild population.
GWEN IFILL: You can find an extended version of that story by following a link on our website.