Poison oak leaves (photo: Jane Huber)

      Stinging Nettle

      Common along the coast, this spiny plant causes an unpleasant stinging sensation when any part of it comes in contact with your skin. It is also mentioned in the hike description when it appears along a given trail.

      Physical Dangers

      Lightning

      Thunderstorms are common during the summer months and often bring lightning, especially at higher elevations. If you see a thunderstorm approaching, avoid exposed ridges and peaks, take shelter in low places, and sit on some sort of insulating material if you feel in real danger; your backpack or sleeping pad are good options.

      Hypothermia

      This life-threatening condition occurs when the body is unable to stay adequately warm and its core temperature begins to drop. Initial symptoms include weakness, mental confusion, and uncontrollable shivering. Cold, wet weather poses the greatest hazard because wet clothes conduct heat away from the body roughly 20 times as fast as dry layers. Fatigue reduces your body’s ability to produce its own heat; wind poses an increased risk as it can quickly strip away warmth. Immediate treatment is critical and entails raising the body’s core temperature: Get out of the wind, take off wet clothes, drink warm beverages, eat simple energy foods, and take shelter in a warm tent or sleeping bag. Do not drink alcohol—this dilates the blood vessels and increases heat loss.

      Heat Stroke

      The opposite of hypothermia, this condition occurs when the body is unable to control its internal temperature and overheats. Usually brought on by excessive exposure to the sun and accompanying dehydration, symptoms include cramping, headache, and mental confusion. Treatment involves rapid, aggressive cooling of the body through whatever means are available—cooling the head and torso is most important—and drinking lots of fluids. Stay hydrated and be sure to carry some type of sun protection for your head if you expect to travel a hot, exposed section of trail.

      Sunburn

      The Northern California sun can fry you quickly—especially at higher elevations, where the air filters less of the damaging UV radiation. Always wear a broad-spectrum sunscreen that provides protection from both UVA and UVB rays (the SPF rating refers only to UVB protection). Wear pants and long sleeves when appropriate, plus a hat with a broad brim to protect your face and neck.

      The Pacific Ocean

      The dangerous waters of the Pacific are frigid, swirling with strong currents and undertows that can instantly suck the unwary out to sea. Rogue waves can always occur, sweeping the unsuspecting from seemingly safe rocks and beaches—especially during times of large swell. Unless you’re confident in your abilities and knowledge of the ocean, don’t tempt fate by going into the water.

      Gear

      Survival Essentials

      You should always have the following:

      Water Carry at least 1 liter of water (preferably 2), drink frequently, and have some means of purifying backcountry sources (chemical treatment or filter).

      Fire and Light Bring waterproof matches and Vaseline-coated cotton balls (or other easy-to-ignite kindling) for starting an emergency fire, along with a headlamp or flashlight in case you’re still hiking at night.

      Survival Gear Pack heavy-duty garbage bags to use as emergency rain protection, shelter, and warmth, plus a whistle to signal for help.

      First-Aid Kit At a minimum this should include an over-the-counter painkiller/swelling reducer such as ibuprofen; a 2-to 4-inch-wide elastic (ACE) bandage for wrapping sprained joints or other injuries; and the basics for treating a bleeding wound: antibiotic ointment, sterile gauze, small bandages, medical tape, and large Band-Aids. Prepackaged kits are readily available at any outdoor-equipment store.