Dangerous Plants

Poodle-Dog Bush

image via US Forest Service
image via US Forest Service

This goofy-named plant you've never heard is a terrible nemesis on the PCT.


Poodle-dog bush (eriodictyon parryi)  is a tall mountain shrub with beautiful purple flowers native to California. Also called Common Turricula, it plays an important role in the process of ecological succession after a forest fire. Until awakened by wildfire, its seeds lie dormant in chaparral areas and yellow pine forests. In a fire’s aftermath, poodle-dog bush covers charred hillsides, holding soil together and preventing erosion until saplings and slower-growing plants return and outcompete it. Its seeds then lie dormant in the soil again, waiting for the next fire.


Key Facts

-  covered in tiny sticky hairs that cause swelling, itching, and rash more painful than poison ivy

-  reeks of marijuana

-  kind of looks like marijuana

-  found in Southern California anywhere that has experienced wildfire in last 10 years

-  has hundreds of small lavender or bluish flowers that appear in clusters, though not all the time

-  can grow 10 feet tall

-  likes elevations between 3,300 and 7,500 feet

-  its toxin is hydroquinone, not the urushiol oil found in poison ivy/oak, so products and treatments that relieve poison ivy/oak do not work


It reeks of marijuana — so much so you’ll smell it before you see it. If there is enough of it growing nearby, the Trail will smell like a college apartment that’s been hot boxed. Every online description we’ve found mentions its “rank” or “pungent” smell, but for some reason no one says it plainly: it smells like the dankest weed you’ve ever had. The leaves even look a little like marijuana, but as far as we can tell, no one has been stupid enough to smoke it. That would certainly put you in the hospital.


Hot Spots

At the moment it’s found only in two Southern California areas (section D) that had wildfires within the past 10 years: the Sheep Fire Burn (miles 345-359) and Station Fire Burn (miles 400-441).


Volunteer maintenance crews from the PCTA (the local Trail Gorillas club) have had the unenviable job of clearing poodle-dog bush from the trailside and have done an excellent job. That said, it still abundant in the hillsides and can reappear along the Trail after crews remove it. It complicates looking for campsites or places to dig a cathole in those areas.

when the PCT passes through burned areas in Southern California like this one, poodle-dog bush is plentiful
when the PCT passes through burned areas in Southern California like this one, poodle-dog bush is plentiful


The plant is covered in sticky hairs (contributing to its marijuana-like appearance) that easily break off, stick to clothing and skin, and release toxins.

  • There is no immediate pain or stinging sensation.
  • Swelling, itching, and rash appear 12 to 48 hours after contact
  • Severe reaction can create large painful blisters
  • For most people, the pain is worse than poison ivy symptoms
  • Symptoms can last several weeks


Removing the Hairs

Since the hairs do not contain urushiol oil, applying Purell, pure alcohol, or a name-brand poison ivy relief product like Zanfel has no positive effect. Instead, you need to remove the tiny hairs you can't necessarily see from your skin, and they are sticky. Rinsing with water won’t do the trick. Instead apply a piece of sticky tape like duct tape or Leukotape to the affected area and then peel it off. Do this a few times and the tape should grab the hairs. Afterward wash the area with soap and water to remove residual oils. Do this as soon as possible after exposure.


Pain Relief

Antihistamines don’t work because the symptoms are not a histamine reaction. Topical anesthetics can help, but only use products with lidocaine or pramoxine (brand names like Aspercreme and Itch-X). Products with benzocaine, like Lanacane may make symptoms worse.


Contaminated Clothes

Wash contaminated clothes in a washing machine with detergent, not a motel bathtub with soap.

Run contaminated clothes through multiple wash cycles – at least three times.

Do not wash uncontaminated clothes with the contaminated ones.



Unfortunately, long sleeves and pants do not fully protect you. The hairs can stick to your clothes if you brush up against the plant, and then later if you touch that part of your clothes the hairs move onto your skin. Regardless, it’s still a good idea to wear long sleeves. The only way to prevent a rash is to prevent contact with the plant.

  • Never scratch your leg with the end of your trekking pole.
  • Never set up camp near poodle dog bush. You might bump into it in the dark.
  • Don’t night hike through the affected sections. You won’t see the plants and they’ll get all over you.
  • If a stem has fallen across the Trail, push it back with your trekking pole until you’re clear
  • Wear long sleeves and pants

Pacific Poison Oak

image via Wikipedia
image via Wikipedia

Pacific poison oak, or Toxicodendron diversilobum, lives across California, Oregon, and Washington and potentially can be found along all parts of the PCT except for the Sierras, where it cannot withstand the extreme elevation and cold. Fortunately, it is not as common as poison ivy is on the Appalachian Trail.


About 15% of people do not develop an allergic reaction to poison oak but the rest of us get a painful itchy rash. This rash is caused by an oil called urushiol (you-ROO-shee-all) found on the leaves, stems, flowers, and roots. Unfortunately, urushiol remains present even after the plant has died.

image via poison-ivy.org
image via poison-ivy.org


Plant ID isn’t always easy, as this photo gallery of Pacific poison oak shows. Like eastern poison ivy, the color and shape of Pacific poison oak’s leaves varies depending upon the sub-species, local environment, and time of year. Leaves change from reddish in spring, green in summer, and yellow, orange, or red in fall, except when they don't.


It can also grow as a ground vine, shrub, or a climbing vine.


Other characteristics are more consistent across sub-species and geography. Poison oak plants typically have leaf arrangements clustered in groups of three leaflets: “Leaves of three, let them be.” The 3-leaf clusters grow in a staggered, left-right pattern, and are never side-by-side. It never has thorns or saw-toothed leaves.


Oak vs Poison Oak

Sometimes poison oak leaves look exactly like normal oaks, and sometimes they don't. It's a crap shoot.


It's Not Contagious

Poison oak rash cannot be spread from person to person. Once on your body, urushiol oil is absorbed into the skin. By the time a rash appears the oil is completely absorbed and cannot be spread by scratching or touching the rash. It can seem like the rash is spreading however. In those cases, the rash is simply not appearing all at once because the urushiol oil was absorbed at different rates on different parts of the body or because there were multiple exposures to urushiol at different times, possibly from contaminated objects or oil trapped under the fingernails.


In severe cases the rash develops blisters. Fluid from these blisters does not contain urushiol and therefore does not spread the rash.


The Oil Spreads via Clothes, Objects

You can get a rash from oil that has stuck to trekking poles, shoes, clothes, backpacks, and gear. Urushiol can remain on gear and clothes for years — in other words it will not break down or dry out and become harmless on its own. You must clean your gear and clothes with soap and water or alcohol.

Cleaning in the field can be frustrating and difficult. A lack of running water, soap, and towels makes thorough cleaning of your clothes and gear difficult. It is best to get into town, check into a motel and clean everything, including yourself, in the shower.


Exposure PreventionLike with poodle-dog bush, long sleeves and pants do not fully protect you. If the oil gets on your clothes it can transfer to your skin. Regardless, it’s still a good idea to wear long sleeves.

  • Never scratch your leg with the end of your trekking pole.
  • Study photos and plant ID guides like this one at poison-ivy.org so that you can quickly spot it and avoid it.
  • Hike in long pants and long sleeves. We recommend doing this for other reasons as well, like preventing sunburn.
  • Wash your clothes and gear whenever you are in town.
  • If you brush up against poison oak or set your backpack down onto it, use your camp towel to wipe your pack down with alcohol (denatured or rubbing). Afterward put the towel in your dirty clothes bag until you can do laundry.
  • If your clothes brush up against poison oak, take them off and keep them outside the tent. You can either try to field-wash the clothes using Dr. Bronner’s, (not camp soap) or simply stash them in a dirty clothes bag and change.

Rash Prevention After Exposure

Even if you touch poison oak, you can prevent a rash if you treat the contact area immediately. The goal is to remove the oil before it is absorbed into your skin. The effectiveness of cleaning decreases with time as your skin absorbs the oil.

  • Rub the area with denatured alcohol or hand sanitizer (which is alcohol based) and wipe clean
  • or wash the area with water and Dr. Bronner's multiple times.
  • Spray Ivy-Off on the area. Its manufacturer claims spraying the product on your skin immediately after contact will prevent a rash.

Field Treatment

You may not realize you have touched poison oak until a rash appears 12 to 72 hours after contact. The rash will slowly improve and disappear on its own over one to three weeks. However, it can be very unpleasant until then. Do not scratch the rash, since bacteria can enter scratches and cause infection. And definitely do not pop any blisters for the same reason. Instead, a number of different options may relieve the itching:

Drug Options

  • products that surround urushiol and bond with it, enabling it to be rinsed away with water like Zanfel and Ivy Off
  • oral antihistamines like diphenhydramine (Benadryl)
  • over-the-counter topical corticosteroids, aka hydrocortisone creams (Cortizone)
  • topical astringents like aluminum acetate (Domeboro)

Non-Drug Options

  • soaking area in cool water
  • using your camp towel as a cool compress