A Growing Passion
Botanic Garden in Your Backyard
Season 8 Episode 6 | 26m 46sVideo has Closed Captions
We focus on the San Diego Botanic Garden's work with plants native to Southern California.
In the second of our two-part series about the San Diego Botanic Garden, we focus on the Garden’s work with plants native to San Diego County and Southern California. The Garden’s onsite collections include three native plant displays: a landscape demonstration garden, a demonstration of plants important to the native Kumeyaay peoples, and chaparral preserve native to the site.
A Growing Passion
Botanic Garden in Your Backyard
Season 8 Episode 6 | 26m 46sVideo has Closed Captions
In the second of our two-part series about the San Diego Botanic Garden, we focus on the Garden’s work with plants native to San Diego County and Southern California. The Garden’s onsite collections include three native plant displays: a landscape demonstration garden, a demonstration of plants important to the native Kumeyaay peoples, and chaparral preserve native to the site.
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♪♪♪ Nan Sterman: San Diego Botanic Garden's mission is to inspire people of all ages to connect with plants and with nature, and it all begins with science.
The Garden's scientific underpinnings may not be obvious to the casual visitor, but they're here, and they're strong.
These curated plant collections serve as a database and a resource for research, conservation, and habitat restoration around the world and right in our own back yard.
As beautiful as these displays are, they have a deeper value, both in our community and around the world.
The dedicated people who curate and care for the plants understand the consequences and the urgency of their work.
Nan: We're behind the scenes talking to the scientists and learning about the crucial role that San Diego Botanic Garden plays in plant conservation locally, nationally, and around the world.
Today, on "A Growing Passion."
♪♪♪ ♪♪♪ Nan: At the San Diego Botanic Garden, science is behind everything you see.
Ari Novy: This is really the best spot in the garden to understand the difference between the Old World succulents and the New World cacti.
Nan: Ari Novy is Executive Director and CEO of the San Diego Botanic Garden.
At heart, Ari is an educator.
Nan: And you know, planting them with the aloes and the euphorbias, it really has a beautiful effect.
Nan: We visited one of my favorite spots: the intersection of the Old World and the New World's succulent gardens.
These two collections demonstrate the fascinating similarities in the way plants evolve, even though they live a world apart.
Nan: What does that mean, "Old World, New World"?
Ari: It's really just sort of an old, Eurocentric kind of an idea, you know, that calls the Old World Europe and the continents connected to or close to Europe, so Asia and Africa and Europe, and then the New World is really North, Central, and South America.
Nan: And why is it important to show the plants in comparison to each other?
Ari: Some really interesting things have happened in the evolution of plants, and, in particular, plants tend to evolve similarly in similar climates and environments.
And the desert, or arid-adaptive, plants are just perfect because even if you're a plant, you know, that evolved in the Southwestern US Desert versus another plant that evolved in the Gobi Desert of Asia, you look very similar, even though you come from a completely different lineage.
Nan: This is the concept of convergent evolution, how very different, unrelated plants adapt in similar ways under very similar environmental conditions.
Nan: A question I get all the time is, What's the difference between an aloe and an agave?
Ari: The agaves are New World, and the aloes are Old World.
And especially when they're not flowering, they look very, very similar.
They have very similar shapes, and that's that convergent evolution.
They're both evolving in deserts in their respective continents, and then they look similar, even though they're not related at all.
Nan: And once they flower, the differences become even clearer.
Ari: The flowers on an agave are a typically much larger and spiked group of flowers, and they're typically yellow or white, whereas the aloes have smaller flowers, and they often come in different colors.
There's a lot of reds in there.
Nan: I always think of those being more tubular shaped.
Ari: "Tubular" is exactly the right word.
Nan: Many of these plants are endangered in their native habitats.
They grow here, in part, to preserve and conserve them and, in part, for us to learn about them while we appreciate their beauty and their value.
More of the Garden's conservation work happens behind the scenes in the nursery and the labs.
All of the information about every plant gets entered into the Garden's sophisticated plant database.
Nan: This is so cool-looking.
This is an epiphytic cactus.
It's called pseudorhipsalis ramulosa.
How do I know that?
Easy.
See this metal tag?
That's called an accession tag.
All botanic gardens use these.
It's a way of cataloging and tracking their collections.
So, when a new plant comes in, it's given an accession tag that stays with it throughout its life.
Brandi Elde: Botanic gardens have documented collections of plants.
And so there is data that is affiliated with many, if not all, of the plants in a botanic garden, and that data can be everything from where the plant was acquired, if it was grown from seed, how old it is, how healthy it is, where we've shared that plant material, if we have, a lot of different information that's really valuable scientifically for us researchers and horticulturists.
Nan: Well, that's pretty.
Brandi: Yeah, this Dudleya is starting to bloom here and looks fantastic, but we can see its accession tag behind it.
So, we've got the accession tags behind or right near the base of these plants, and it's got the accession number, and that's the number, again, that's gonna tell us all of the information we need to know in our database, tells us where it is physically in place, where it came from, and any other information that's useful to us.
Nan: So, it's like the dog tag for the plant.
Brandi: It is, it is, and it's unique to this plant.
If we have another Dudleya over there, it will have a different number.
Nan: Accession data is especially important for tracking and monitoring rare and endangered plants, where plant parentage can make the difference between survival and extinction.
Nan: Brandi, this is not the most beautiful plant I've ever seen.
So, what's it doing in a botanic garden?
Brandi: Well, that's a great question.
We have a lot of beautiful plants in botanic gardens, but we also have some--sometimes scrappy-looking plants that you might not know why they're here, but all of these plants serve a pretty critical role in the ecosystem, and botanic gardens have a role in preserving them.
These are an Encinitas Baccharis, the Baccharis vanessae.
You can see the accession tag affiliated with each one here, and that's going to give us unique individual information as to which parent the plant seed was collected from.
Nan: So, what's the story behind these?
Why are these here?
Brandi: It has a really amazing story in that it's, really, only native to San Diego County mostly, and there's a population in Encinitas where there are only 26 individuals.
And so Tony Gurnoe has led some efforts to gather the seed, grow them out, and now there are 120 from that population in pots or in the ground, and we've shared with eight other botanic gardens, as well as collected 14,000 individual seeds to go into seed banks.
Nan: So, there's only 26 now.
Were there more before?
Brandi: There used to be a lot more, hundreds if not thousands, at least in the Encinitas area.
On the coastal bluffs is where they're native to, which is a beautiful spot that people also like to live, and so that poses a lot of threats with habitat loss.
Nan: So, this is, like, a classic example of urbanization causing plant extinction-- or almost-extinction.
Brandi: Yes, exactly.
Nan: So, will we stop extinction with this?
Brandi: Well, that's the goal, yes.
And with the dissemination efforts that we've started here in sharing with other botanic gardens, we've really taken some steps.
And a lot of the plant material that was grown out from that population are used in some restoration plans that we have off site.
Nan: So, this is plant conservation in our own backyard.
Brandi: It certainly is.
♪♪♪ Nan: Tony Gurnoe is the Garden's Manager of Conservation Horticulture.
He's responsible for the Garden's conservation work both onsite and off.
Tony works in concert with botanists and conservationists around the world and right here at home to protect and preserve the planet's plant diversity.
Nan: Well, we made it through the jungle.
Tony Gurnoe: Yeah, out to this cliffside here, a little bit of Hawaiian cliff garden here.
Nan: What are we looking at?
Tony: These plants actually come from a small stretch of Kauai--or at least they used to.
Nan: They used to.
Tony: Yeah, this is brighamia insignis, and we've been growing them in this garden for a couple of decades at this point.
And in that same time, they've actually gone extinct in the wild.
Nan: Oh, really?
Tony: Yeah, the story on these things is quite dramatic.
It involves goats eating a lot of the plants, wildfires coming through, even in a place like cliffs of Hawaii.
And to top it all off, the one insect that pollinated these things went extinct just before a hurricane came through and basically swept the remaining population off of the island.
Nan: That sounds like the storyline of a really bad movie.
Tony: I don't know if these plants, as a species, are cursed or what, but we're trying to help them.
And one of the ways that we're doing that is by strategic propagation.
Every one of these has been genetically sampled.
And so we know how much this one relates to that one and how much any of these relate to the plants, for instance, still in Hawaii at other gardens or in other parts of the country.
Nan: So, in botanic gardens on display, not in their native habitat.
Tony: They really don't exist in their native habitat any longer, and so every one of these plants is in captivity, so to speak, which gives us an interesting opportunity to have much more oversight over their future.
Nan: So, what are you gonna do?
Are you gonna pollinate these and make seed?
Tony: We're both gonna pollinate these and make seed and grow them out in our nursery, but also send some of our pollen and genetics to Hawaii so that they can do breeding there as well.
Ultimately, we hope to bring all these plants together and put out a whole new population where they once existed.
Nan: So, you're gonna use the horticultural specimens to repopulate the native population.
Tony: It's really all that is left, and so this plant and its foreseeable future as a species are at the hands of gardeners.
Nan: Encinitas's mild climate is perfect for a wide range of rare and endangered plants.
That's fortunate, since botanic gardens serve as repositories for an ever-increasing number of threatened plants around the world.
Tony: This is actually microcycas.
It's one species in this genus, and this is it: microcycas calocoma.
Nan: Where is it from?
Tony: This is from Cuba.
Nan: Cuba.
And why do you have this?
Tony: Well, it's endemic to Cuba, which means that they only naturally grow there, and as you can imagine, it's not the easiest place to come and go as an American botanist.
Nan: Right.
Tony: And our colleagues at the Montgomery Botanical Center in Florida have been able to get some of the seeds from habitat and grow them on.
And this is progeny from their plants, and this is something rare enough that instead of it being available for sale, they're offering it to other institutions like us as additional safeguard.
Nan: So, in other words, they're expanding their collection by making sure you have some, and somebody else has some.
In case they lose theirs, it still exists.
Tony: That's exactly it.
It's the concept of not having all of our eggs in one basket, and it's been demonstrated as important with many of the natural disasters that have afflicted botanical gardens over the last several years.
Nan: This is painstaking work.
Successfully breeding, growing, and tracking plant genetics is a huge undertaking.
In fact, it takes an international community to do this work.
Tony: These are quercus toumeyi, which is a southwestern scrub oak, and these were collected as acorns in Arizona.
Nan: Wow, but what are they doing here?
Tony: These are part of a project called the tree gene conservation project.
And what that means is that these were collected with the intent to disseminate the acorns to a whole bunch of different gardens, specifically because you can't put acorns, quercus seeds, oak seeds into a freezer for seed banking.
Nan: Oh, so when you collect them, you have to use them right away.
Tony: You have to grow these in order to conserve and preserve them.
And so what we're doing is serving as one of the sites that is a safeguard for this species among many of our partner institutions around the country.
Nan: I've seen these before.
Tony: This is one of my favorites, and these are actually great landscape material for our area.
Nan: Yeah, these are tecate cypress.
We did a whole episode on tecate cypress and endangered plants, and I use them in landscapes, too.
But why--you have them here for what reason?
Tony: Well, you're one of the few people that I know who's actually been out to see them where they grow, and it's a small spot.
There aren't that many of these overall, and being that they're wonderful in the trade, we wanted to bring some of that wild genetics into the trade and to essentially diversify and make what's out there even more interesting.
Nan: And what about this?
This looks like a magnolia.
Tony: Magnolia is a similar story to the quercus toumeyi in front of me, which is that this is part of a tree gene conservation project, where magnolia, as well as oaks, the seeds cannot be put into the freezer for long-term storage.
And again, you have to grow it in order to preserve it.
Nan: There is just so much happening here that the average visitor has no idea, Tony.
I mean, the kind of things you're involved in-- international, preservation, restoration, you know, building up numbers of things that have disappeared.
It's really amazing.
Tony: I hope that people can appreciate that, because one of my favorite things that's incapsulated here is this concept of-- that the best way to preserve a plant is to share it.
And we're working hard to do a lot of that.
Nan: Growing plants outside their native habitat is a critical component of plant preservation.
As native habitats are increasingly threatened, botanic gardens hold the key to protecting species while creating public awareness.
And by working together, they're maintaining a living collection of genetic diversity that becomes more critical with each passing year.
Nan: The Garden grows some of the rarest plants on Earth, a remnant from the days of the dinosaurs: cycads.
Cycads are the most threatened plant group in the world.
These beauties disappear as humans destroy their native habitats or the plants fall prey to illegal poaching and end up in the collectors' market.
Nan: Nearly every kind of cycad is protected in the wild, which means they can't be collected, but poachers don't care about laws.
They see dollar signs.
So, there's an effort underway to reproduce cycads in captivity, get them on the market, drive the prices down, and that discourages poachers from depleting those native populations.
Nan: This is a gorgeous, huge cycad.
Which one is it?
Tony: This is encephalartos kisambo, only from Kenya.
Nan: Only from Kenya.
And this is a female, obviously.
Tony: It is, and the cones are ready for pollen.
Nan: In nature, tiny beetles would pollinate these cones.
But since those beetles don't live here, Tony's improvised a solution.
Tony: So, I'm gonna plunge this and let the pollen in solution actually flow through the inside of this cone and hope that the little bits of pollen actually connect with the ovules inside.
Over the course of a couple of weeks, do it several different times, if you have the pollen for it.
Nan: So, okay, this is plant artificial insemination, right?
Tony: Essentially, yes.
Nan: Does it work?
Tony: It does.
We might get 200 seeds out of this.
Nan: Oh, that really does work.
Tony: This is a long-time investment, and it might actually take eight to ten months before these seeds are ready to collect.
Nan: Tony cut one of the cycad cones to show us what they look like inside.
This is heavy.
And when you cut it open, you can see these orange things.
This is what we were calling the ovules.
They're the pre-seeds, and they are ready to be pollinated.
The pollen would be deposited by a little beetle right here, work its way up into the ovule, and then that becomes a seed.
Tony: Give it enough time, and the whole cone starts to break apart like this, and these are the results and mature seeds of encephalartos ferox, which we pollinated.
Nan: So, this is really fleshy.
And what would happen is these would fall on the ground, and they would sit there, and the fleshy part would wear away, and then the seed would germinate.
Or it could possibly have been eaten by an animal, right?
Tony: Yeah, but it's worth noting that these are quite poisonous.
And usually, if you see something this color, you should be wary of it.
Nan: Right, so don't ever eat these.
Don't feed them to your dog.
Don't give them to your little kids.
But do watch them, because they're fascinating.
Nan: Ironically, among the Garden's collections of endangered plants, one of the most endangered is more than local.
It's native right here on-site.
Tony: This is all maritime chaparral, specifically southern maritime chaparral.
It's a very rare piece of an overall rare type of plant community.
Nan: There's more rare plants here probably than anywhere else, right?
Tony: San Diego actually has more endangered, or plants that only grow here, than of any county in the whole country.
Nan: Is this the same habitat as on the other side?
Tony: Yeah, this is all part of the same southern maritime chaparral that you only find on these coastal bluffs.
Early on, when the Garden was developing as a public botanical garden, this space was seen as an opportunity to "Let's do something there later on," until it dawned on everybody that the plants in this area are among the most important in our whole botanical collection.
Nan: So, it's kind of ironic.
You've got these collections of plants from other places, but the plants that are actually from here are some of the most endangered.
Tony: Yeah, it's a really wonderful thing from where I sit, because I get to work with rare plants that are doing their own thing naturally right next to plants that are exotic, endangered species from around the world.
Nan: Southern maritime chaparral is specific to the humid coastal strip, where temperature changes are minimal: summers are dry and warm, while winters are cool and wet.
This climate attracts people, too.
In fact, human development is the greatest threat to this rare habitat.
The Garden's conservation mission extends out into the community as well.
Tony and I visited Oakcrest Park, just a mile or two away.
Here, the Garden and the City of Encinitas are working together to protect and restore another small patch of the locally native southern maritime chaparral.
Nan: Well, that's a nice view.
Tony: You can see quite a bit of Encinitas from here.
Nan: What you really see is how small and compact this wild area is.
How many acres do you think you have?
Tony: Yeah, that's true.
This is probably a little over ten acres.
Nan: So, that's not much.
And yet, I've been here a million times.
It never occurred to me that I was looking at something really special.
Nan: Even in native habitats, some kinds of plants outcompete others.
With so little southern maritime chaparral left, Tony and others are hoping to add more diversity to this precious habitat.
Tony: This is actually one of the reasons that this park is preserved at all.
This is one of the rarest plants in the world, actually.
Nan: What is it?
Tony: This is del mar manzanita.
Nan: So, I can tell it's a manzanita.
What makes it special?
Tony: This only has ever been documented to grow on these coastal bluffs from about Torrey Pines to Carlsbad and not very far inland at all.
Nan: So, when you have a plant like this, what's the long-term vision?
What are you trying to accomplish here?
Tony: I'll tell you that more than 95% of the previous natural range of this species is developed in some form-- highways, hospitals, schools, homes, and so on.
The future for this species has to be managed in some ways.
And so having a space like this, which is carved out for them to have a home, is a start, but it's not the end of the story.
Tony: We're getting a little bit into the shrubbery now.
Nan: One conservation success story involves a very rare plant called Encinitas baccharis.
Nan: Here we go.
Nan: We saw it growing in the Garden's nursery and planted out in the collections.
Tony: Here we are.
Look at this baccharis vanessae.
Nan: There are just two dozen of the species left in the wild.
Nan: But you're planting these in the Garden, too, right?
Tony: We put more than 60 of these into the Garden.
Nan: Each plant is numbered and documented in the Garden's database.
Tony collected the seeds and germinated them to establish the Garden's baccharis collection.
Now, he'll continue to propagate them, study them, and hopefully reintroduce the plant into habitat.
He's doing similar work with del mar manzanita.
Tony: We actually do have one baby plant in this dish.
Nan: Oh my gosh, look at that.
The little bit of green for the stem and then the brown for the root.
Tony: And not only is del mar manzanita in cultivation any way really significant, but from seed it's almost unheard of.
This is pretty revolutionary.
Nan: Oakcrest Park is just one park of a larger plan to restore southern maritime chaparral around Encinitas.
Tony: We are at the back end of the Cottonwood Creek Park, where the city and the state partnered to create this really nice playground, lawns, that type of a park.
Where we are actually becomes open natural space, and there's a riparian zone, where the Cottonwood Creek watershed here just before outflowing to the ocean at Moonlight Beach.
Tony: First, removing the invasive species and any of the problem stuff, and then returning the plants that should and used to actually naturally be here.
Nan: Some non-native plants do so well here, they become invasive, which means they crowd out the natives.
When that happens, native birds, insects, and other creatures lose their homes, too.
It's an environmental disaster.
So, Tony collects seeds and cuttings from local natives to grow out at the Garden.
On Saturdays, volunteers come to help replant these threatened habitats.
This is restoration.
Tony: Dig a small hole, stick the plant right in it, water it, and walk away.
That's part of the beauty of working with native plants is that they don't need anything from us that this environment doesn't naturally provide for them.
Tony: Within our volunteer ranks, we have some incredible wildlife biologists, even.
We have volunteers who have been helping us to collect propagules, whether that's cuttings or seeds from this site, and grow them out in our nursery in order to bring them back to this restoration site.
We have volunteers who are helping to actually remove straight-up trash.
Jeff Schaffer: When we came here, Tony gave us a tour through.
It was tremendously overgrown.
And I'm sort of the donkey guy.
I love just ripping into it and making huge piles.
That's one of my piles right there.
♪♪♪ Tony: The positives to bringing the native plants back in go well beyond just the plant scape.
And a big part of what we're trying to do here is to create better bird habitat.
The one that we're really steering our planting toward is the California gnat catcher, and they love coastal sage scrub.
They don't have any use for ice plant instead or mustards.
And those invasive species not only cause problems that relate to fire and things of that sort, but they really don't provide anything to the animals, the pollinating insects, all of those domino effects of an ecological system.
So, we're doing a lot of different things here, and volunteers are involved in every facet of it.
Nan: Protecting and preserving native habitats, raising awareness about the value of plants, and safeguarding their future, the San Diego Botanic Garden is doing all this and more.
Ari: Probably the most important thing that it needs to do well is help people understand not only why plants are important but that they have a role in stewarding our entire planted planet.
We don't want any plants to go extinct.
And more so than that, we want those plants to stay healthy and thriving in their natural ecosystems.
Nan: This peek into the Garden's vitally important conservation work helps us understand and appreciate this planet we call home.
♪♪♪ Nan: Connect with us at "A Growing Passion" for garden tips, behind-the-scenes updates, and to see what's growing in California.
Watch all of our shows online any time at agrowingpassion.com.
Nan: These plants may not capture your imagination the same way as rhinos or elephants, but their conservation is just as important.
The plants here and the professionals who manage them are part of a vast network focused on stopping plant extinction in distant lands and right here at home.
I'm Nan Sterman.
Thanks for watching.
♪♪♪ ♪♪♪ ♪♪♪ ♪♪♪ announcer: Support for this program comes from the KPBS Explore local content fund, supporting new ideas and programs for San Diego.