The hillsides around Castaic Lake are still charred.

But hundreds of oak shoots are breaking through the ash.

What’s growing back — and what isn’t — was decided years before the fire.

Across Southern California, TreePeople is restoring landscapes where invasive plants have overtaken native species after wildfires — helping ecosystems recover on their own the next time flames ignite.

Invasive mustard dominated the hillsides around Castaic Lake after a wildfire in 2002. Twenty years later, TreePeople replaced it with native live oaks and scrub oaks.

In 2025, the Hughes Fire burned more than 10,000 acres near the lake — including 25 acres that TreePeople had restored.

Now, a year after the fire, more than 1,400 native tree saplings have sprouted. 

The Threat Above Ground

After wildfires, invasive plants often return first, crowding out native species and reshaping the ecosystem.

TreePeople is working to reverse that trend. They’re replacing invasive plants with more than 100 species of native plants and trees at 20 sites across Southern California.

“If we can bring some native species back in, the whole trophic chain starts to reestablish,” Alyssa Walker, the Associate Director of Conservation at TreePeople, said. “If we don’t step in, you’re not going to have the same pollinators, and then up the chain, everything is altered.”

For Alyssa and her team, the question isn’t if the land will burn again — it’s when.

“There’s no doubt in our minds that it’s going to burn again. With climate change, we’re seeing fires become more frequent and more unpredictable,” Alyssa said. “But if the plants are native, the landscape is going to be more resilient.”

She looks to nearby Placerita Canyon Nature Center for proof. The area has burned and recovered three times since 2004.

The Threat Below Ground

Wildfires aren’t the biggest threat to many young trees.

Long before flames ignite, gophers often chew through roots, stopping trees from establishing.

“From the nursery to the field, you put so much care into growing and planting these trees, only for them to die once the gophers find them,” Alyssa said. “It’s pretty disappointing. After a while, you almost start to accept it.”

For years, her team built chicken wire cages to protect each tree’s roots — a slow process that limited how many trees they could plant.

That changed when they started using Vole King baskets.

Tree survival rates increased from roughly 20-40% to 60-80%.

“In Southern California, we’re in a race against everything — when’s the next rain, when’s the next fire?” Alyssa said. “Having a product that’s as easy as possible to assemble has changed the game. We’ve been able to scale up in a way we wouldn’t have been able to otherwise.”

Last year alone, her team planted 19,625 native trees.

What You Can Do

Whether you live in a fire-prone area or not, planting native species in your own backyard can strengthen your local ecosystem.

You can use tools like the National Wildlife Federation’s Native Plant Finder to find what plants are native to your area.

“Even if you’re creating just slightly more habitat for a pollinator to come through and rest, that pollinator is feeding the whole trophic system in a ripple effect that we don’t even see,” Alyssa said.

Planning native trees is her way of thanking nature for all it does for us.

“The beauty of nature is so inherent to our well-being — not only for our physical health, but our mental health,” Alyssa said. “It feels natural to want to give back. This land gives me so much, and I want to give back as much as I can.”

What Comes Next

Investigators don’t know whether the Hughes Fire was accidental or intentional.

But TreePeople knows what has grown back this time is intentional — and what will grow back next time is already taking root.