Eucalyptus trees are big, they’re everywhere, they smell, and they make a mess. If you own property on the Central Coast — Santa Cruz County in particular — you either have one or your neighbor does. Most people assume a tree this size must be good for something. It isn’t.

A Timber Boom That Never Happened

Eucalyptus is native to Australia. In the late 1800s, California was developing fast and needed timber. Someone noticed that eucalyptus grew unusually fast, and speculators planted tens of thousands of acres of blue gum (Eucalyptus globulus) up and down the coast. The idea was simple: plant now, harvest durable hardwood in 10 to 15 years, and make a nice return.

It didn’t work. The wood turned out to be nearly unusable, the trees were abandoned in place, and they kept spreading. Stumps resprouted. Seeds traveled. Santa Cruz County’s marine layer and mild temperatures were ideal. Nobody cleared them because nobody wanted to pay for it.

Why the Wood Is Basically Useless

A 150-foot tree that grows six to eight feet per year sounds like a valuable resource. But it isn’t.

The problem is something called checking. As eucalyptus wood dries, the outer layers shrink faster than the interior. The wood splits — sometimes within days of milling. The faster the tree grew, the worse it is. Kiln drying helps but is slow and expensive, and the wood still moves unpredictably afterward. It doesn’t hold fasteners well. It dulls blades. For anything structural — framing, decking, fencing, furniture — it doesn’t work.

Eucalyptus trees on the Central Coast are not suitable for lumber, structural use, or firewood without extended seasoning. Freshly cut eucalyptus needs to season for at least a year, ideally two, before it burns cleanly. Cut it green and you get smoky fires and creosote-coated chimneys.

This is why we have so many of them. If the wood had been useful, the groves would have been harvested. They weren’t, and 150 years later, here we are.

What You Need to Know If One Is in Your Yard

They Drop Branches Without Warning

Large limbs fall on calm, dry days with no obvious cause — arborists call it sudden branch drop syndrome. Whole trees can go down in storms, particularly in the clay soils common throughout Santa Cruz County. If one is within striking distance of your home, get a professional assessment from an ISA-certified arborist.

They Are a Serious Fire Hazard

The oils in eucalyptus leaves and bark ignite at low temperatures and throw embers well ahead of a fire front. The 1991 Oakland Hills fire, which killed 25 people and destroyed nearly 3,000 structures, burned through eucalyptus. In the Santa Cruz Mountains and other high-risk zones in Santa Cruz County, keeping leaf and bark litter cleared from around structures is not optional.

They Are Aggressive

Constant debris, root systems that deplete groundwater, chemicals that suppress native plants underneath — eucalyptus is not a low-maintenance tree. If you’re buying property in Santa Cruz County with mature eucalyptus on it, budget for removal or ongoing management. Tree removal can affect your home’s value, depending on the situation.

Removal May Require a Permit

Santa Cruz County and several cities in the region have tree protection ordinances that cover eucalyptus. Check with your local planning department before you hire anyone.

Frequently Asked Questions

Is eucalyptus wood usable for construction in Santa Cruz County?

No. Eucalyptus blue gum is not suitable for framing, decking, fencing, or furniture. It splits as it dries, doesn’t hold fasteners well, and moves unpredictably after kiln drying.

Can I use eucalyptus as firewood in Santa Cruz County?

Only after extended seasoning. Freshly cut eucalyptus needs at least a year to dry — ideally two — before it burns cleanly. Green eucalyptus produces heavy smoke and coats chimneys with creosote.

Do I need a permit to remove a eucalyptus tree in Santa Cruz County?

Possibly. Santa Cruz County and several cities in the region have tree protection ordinances that may apply. Check with your local planning department before hiring anyone.

Are eucalyptus trees a fire hazard in Santa Cruz County?

Yes. The oils in eucalyptus leaves and bark ignite easily and throw embers ahead of a fire front. In fire-prone areas of Santa Cruz County — including the Santa Cruz Mountains — clearing leaf and bark litter from around structures is essential.

Why are there so many eucalyptus trees in Santa Cruz County?

They were planted in the late 1800s as a timber investment that failed. The wood turned out to be nearly unusable, the groves were abandoned, and the trees spread on their own. Nobody cleared them because nobody wanted to pay for it.

The Bottom Line

The blue gum arrived as a timber investment. The investment failed. The trees stayed. If you’re buying property in Santa Cruz County, know what you’re inheriting. If you already own it, know what you’re managing.

I’ve spent more than 35 years helping buyers and sellers in Santa Cruz County, Monterey County, and Santa Clara County. Eucalyptus comes up more than you’d think — removal costs, fire insurance implications, permit requirements before close. If a tree situation is part of a transaction you’re working through, give me a call.