California Landscape Design

LA Biodiversity Symposium

 In November, APLD of greater Los Angeles hosted a one-week-long Los Angeles Biodiversity Symposium, cosponsored by LA Sanitation and Environment (LASAN). Our city of Los Angeles has been designated a global biodiversity hotspot – one of only 36 in the world. LA has this designation because of the incredible ecological diversity that stems from the extraordinarily varied geography of our area. In fact, Los Angeles is the only city in the US that has a major mountain range running right through it with over 5000 ft of elevation changes. Sadly, this designation also means that the area’s biodiversity is severely threatened by urban development. 

We heard from 10 speakers – a varied mixture of scientists, horticulturalists, landscape architects and historians.

Why is Biodiversity important?

LASAN explains the importance of Biodiversity as follows: “The survival and well-being of the City’s residents also depend on ecosystem services provided by biodiversity, including air pollution reduction, strongly and rapidly mitigating and adapting to climate change, mental health and educational opportunities, water cleansing, and aesthetic benefits. These services are built directly from an integrated ecosystem of natural biodiversity and sustainable urban landscapes.” 

Take the humble tree for example. Its incalculable benefits include sequestering carbon, supporting wildlife habitat, providing green infrastructure, creating a shade canopy, retaining water, reducing air pollution, and improving life quality.

What did the Biodiversity Symposium teach me?

I learned from Councilman Paul Koretz’s introduction that the city of Los Angeles is extraordinarily forward thinking in its green policies. His many initiatives include the Healthy Parks/Healthy Soils Initiative, Wildlife Habitat Connectivity and the LA Biodiversity Index.

I learned about the city’s Biodiversity Index – only the 2nd in the world – from Dr. Mas Dojiri and Michelle Barton of LASAN. They are cataloging the area’s biodiversity using 25 separate metrics (like habitat quality) with the aim to protect and enhance biodiversity with a goal of No-Net-Loss by 2035.

Dr. Isaac Brown taught me about the concept of Ecotopes which breaks down regions into smaller subregions to help manage the city as an urban ecosystem. LA city alone has 17 separate ecotopes. They are working on producing a decision support and wildlife connectivity tool that will be zip code specific. Type in a zip code and you will get information on the historic ecology, pollution exposure, type of soils, tree canopy and the area’s native plant community. 

I learned about the importance of community science apps like iNaturalist from Lila Higgins of the Natural History Museum. Lila leads the charge on community science with programs like City Nature Challenge. Using iNat, users share their observations of nature to document plants and animals and share them with scientific data repositories like the Global Biodiversity Information Facility to help scientists find and use the data. If you haven’t seen Lila’s TedX talk, or read Wild LA, the book she co-authored, I’d highly recommend doing so. For a quick tutorial on using iNaturalist see resources below.

I learned from Dr. Eric Wood, principle at Avian Ecology and Conservation Lab, that as part of the Pacific Flyway, we support millions of migratory birds throughout the wintering period and they live and dine in our urban forest of which 10 – 20% is comprised of street trees, making their selection critical. While there are many, many more exotic trees planted as street trees than natives, migratory birds vastly prefer native trees for their food and habitat. 

I learned the importance of Wildlife Connectivity in our cities from Kat Superfisky, LA’s urban ecologist. Kat explained that the fragmentation of our landscape by roadways, railways and development has caused massive challenges to our wildlife and creating wildlife corridors to connect areas is key for maintaining the health and stability of our city and region. Take the case of our famous Mountain Lion P22 who, after crossing 2 major freeways is marooned in Griffith Park. 

Esteemed native plant horticulturalist, Carol Bornstein, showed me how the Natural History Museum transformed its infertile parking lot into a 2.5-acre wildlife habitat brimming with native plants and biota creating a place of healing and learning. Carol gave us a primer on some of the impressive 3000 native plants indigenous to Los Angeles County.

Natalie Zappia and Don Larson showed me that you can create native biodiversity anywhere. They are co-opting barren lots all over the valley and creating tiny sustainable pollinator gardens with ecological, cultural & community, economic and culinary layers of diversity encouraging community involvement.

I learned from herpetologist Dr. Brad Shaffer that we shouldn’t be looking at gophers and small tunneling mammals as an enemy that need to be chased away. These tunnels play a huge part in ensuring biodiversity as reptiles and small mammals rely on them to survive.

In Dr Eric Strauss’s fascinating lecture, he explained that we must stop seeing cities as the problem but rather see them as the solution. Cities should be viewed as legitimate ecosystems that perform the important services of nature. 

One theme that kept recurring was the pattern of higher biodiversity in affluent neighborhoods known as the “luxury effect”. While access to nature should be a human right and urban amenity, benefits of urban biodiversity are unequally distributed. This is particularly the case in low-income neighborhoods with higher minority populations where there is less access to natural areas, fewer trees, higher exposure to pollutants, scanter tree canopy and vegetation biomass resulting in fewer birds, insects and animals, and an alienation from the healing powers of nature.

I was awed by the enthusiasm and commitment of this incredible group of environmentalists and ecologists committed to finding ways to heal the environment. As landscape designers we are in a unique position to implement these techniques in creating landscapes that sequester carbon dioxide, conserve water and ensure that biodiversity flourishes in our region. We can be stewards of nature and turn our planted landscapes into effective biological corridors. Historically, cities have been built with only human citizens in mind. It’s imperative to reconsider this approach to ensure our survival … and we must be part of that change. 

5 Takeaways from the LA Biodiversity Symposium:

1. Use California native plants – wherever you can and as much as you can. 

2. Get the apps iNaturalist and ebird and start using them.

3. Certify your gardens as Wildlife Habitats through the National Wildlife Federation.

4. Use Integrated Pest Management Practices (IPM) and eschew rodenticides.

5. Use Calscape, Calflora Native and plant nursery websites. They are an important resource.

List of Links

Urban Eco-Lab
LA River Watershed Map
iNaturalist Tutorial
Tree Canopy Map Viewer CURes
SSurgo Soils Data