Sonoma County parks, trails see invasion of poison oak, ticks and other pests

Lush greenery, gurgling streams and cascading waterfalls are some of the welcome signs across the North Coast that five years of punishing drought are behind us.

But be warned. Torrential rains also are fueling a bumper crop of poison oak along with copious numbers of ticks, mosquitoes and other pests.

Many are learning that the hard way after getting home from an outdoor adventure and discovering they or their pets are covered in ticks. Or days later, after they have broken out with a rash from contact with poison oak.

“It's coming in real thick,” Scott Lawyer, field operations manager for Stewards of the Coast and Redwoods, said of poison oak at Austin Creek State Recreation Area and Armstrong Redwoods State Natural Reserve near Guerneville.

At Trione-Annadel State Park in Santa Rosa, veteran ranger Bob Birkland said he looked down after he finished clearing an oak tree limb from a fire road this week to see black specks covering his work pants.

Ticks. Lots and lots of them.

“I'd rather be bitten by a rattlesnake than a tick,” Birkland said, citing fears of Lyme disease, which can be borne by ticks.

Birkland said moisture-laden tree limbs covered in poison oak are drooping along trails at Trione-Annadel, ripe for contact with hikers, bike riders and equestrians. The veteran ranger is accustomed to such conditions, which is why he keeps a bottle of Tecnu in his shower. The solution, available at any pharmacy, is said to remove oils from poison oak that can lead to rashes.

Birkland said he also washes his work clothes separately to prevent contamination.

Pomo Canyon Trail between Shell Beach and Willow Creek near Jenner is so overgrown with poison oak, blackberry bushes and stinging nettles that the growth nearly prevents through-access in some spots, according to Mark Anderson, the trail patrol volunteer for state parks in the Russian River area.

At Sugarloaf Ridge State Park near Kenwood, poison oak is “thriving,” said Richard Dale, executive director of the Sonoma Ecology Center, which comprises part of the team that manages the park.

Dale noted that poison oak, which is native to this part of California, has a beneficial relationship with the ecosystem. Deer and squirrels prefer it as a food source, while the plant's deep roots are good for erosion control.

Dale's crews are leaving poison oak mostly where it is at Sugarloaf, other than clearing it away from campgrounds. At Armstrong Redwoods, Lawyer said he's prevented from doing too much about poison oak because of its status as a native species.

“You can trim it off trails if it's overgrowing trails, but that's as far as it goes,” he said.

Sonoma County Regional Parks is taking a novel approach to dealing with the problem at Helen Putnam Regional Park southwest of Petaluma.

By letting sheep graze on poison oak near trails and areas of undergrowth, officials hope to reduce levels of the rash-inducing plant, along with other plants contributing to a higher risk of fire danger, according to Melanie Parker, the agency's natural resource manager.

The pilot program, which launches in early May, could expand to other regional parks depending on how things go, Parker said.

“In parks and preserves where we've taken fire and grazing out, it's favored a poison oak undergrowth. Helen Putnam is a poster child for that,” Parker said.

Lynn Mortensen, a Kaiser-Permanente family physician in Santa Rosa, said she treated two cases of poison oak rash Tuesday.

She said unless it's a severe case covering a large area of the body, standard treatments for such rashes are itch-relieving ointments and cold compresses.

Mortensen, who lives near Trione-Annadel, said the grasses are so tall at the park this year that they may be obscuring poison oak lurking in the undergrowth. Ticks also love hanging out on the ends of the stalks.

Mortensen advised park visitors to wear long pants and to tuck them into their shoes or hiking boots. Wearing light clothes makes it easier to see ticks.

Tick nymphs, which are no larger than poppy seeds, are of greatest concern for the bacteria that causes Lyme disease, said Nizza Sequeira, a spokeswoman for the Marin-Sonoma Mosquito and Vector Control District.

She recommended people run their clothes in the dryer for 10 minutes to kill ticks after they return home from an outdoor adventure, and use a bug repellent containing DEET (the insect repellent diethyltoluamide) prior to heading out.

Using DEET is also the advice to fight mosquitoes, which are just now starting to proliferate in the region.

All this has become evident across the North Bay, where swatting, scratching and sneezing are the unfortunate side effects of what otherwise has been glorious relief from drought conditions.

You can reach Staff Writer Derek Moore at 707-521-5336 or derek.moore@pressdemocrat.com. On Twitter @deadlinederek.