Don't Be Fooled, This Vibrant Yellow Plant is a Super Bloom Bully

Black mustard might look Instagram-worthy, but it's actually an aggressive non-native weed that contributes to long-term problems

There's a super bloom impostor out there, masquerading as a colorful wildflower as it blankets some of Southern California's scenic hillsides.

From a distance, it looks like a vibrant yellow flower -- just another part of the rich tapestry that bloomed after a wet winter. Maybe you've even seen it in a few Instagram posts.

But black mustard is actually a harmful weed that can push out native plants like California's celebrated poppies, lupines and others. The aggressive bully of a weed spread this spring along the 101 Freeway, Pacific Coast Highway, Mulholland Highway and locations throughout the Santa Monica Mountains. 

The winter annual produces chemicals that prevent native plant germination. They also grow quickly, sucking up water that would otherwise be available for native plants.

Black mustard has already taken over wildfire-scarred hillsides in the Malibu area, growing up to 10 feet tall in clumps with thick stalks that make it difficult for hikers and mountain bikers when it overruns trails. 

And, the problems don't end there.

"In a couple of months, the mustard will dry out, turn brown and become tinder for wildfire," said Joseph Algiers, a restoration ecologist for Santa Monica Mountains National Recreation Area. "Sadly, newly burned sites are more subject to invasion."

Of the 300 non-native plant species in the Santa Monica Mountains, biologists have identified the worst offenders as the Evil 25, but black mustard isn't part of the list. There are projects in place to combat the spread of plants on the list, but black mustard is another type of beast.  

"It would probably be easier to get another man on the moon than to get rid of this invasive plant on a regional scale," Algiers said.

The National Park Service is looking for volunteers to help battle invasive plants. Click here for information.

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