Most surfers, snorkelers, and ocean swimmers know that sharks and currents aren't the only hazards in ocean water. Jellyfish are becoming an increasing danger all over the world.

There are over 200 known species of jellyfish, and 70 of them sting. Jellyfish can detect changes around them, and react to changes. When they contact something solid, their reaction is to sting. The stinging mechanisms are nematocysts, capsules containing hollow coiled threads with barbs all along their length. There are hundreds of nematocysts on each tentacle and feeding arm of a jellyfish.

The most dangerous jellyfish is the sea wasp, a small box jelly found from Australia to Malaya. Their sting can be deadly because of the high toxicity of their venom. A person stung by a sea wasp can die within minutes, either from the toxin or from drowning because of the paralysis the sting causes. If you're in those waters, wear a full-body wetsuit to survive.

Sea wasps aren't in American waters but larger box jellyfish are. These jellyfish don't have the dome or bell shape that characterizes the class. Their sting is very painful, and if they are swarming and you're caught in the swarm, the number of stings can be lethal. If warnings are posted, or if you can see them, stay out of the water.

The other dangerous jellyfish is the Portuguese man-of-war. These aren't true jellyfish, but have the characteristic dome shape. They're recognizable by their blue color. Even dead ones washed ashore can sting. They're increasing in number as ocean temperatures rise, and moving steadily north.

You can survive a jellyfish sting by treating it with vinegar, so carry a bottle or two of that along with your bottle of drinking water. Carry allergy medications in your pack too because allergic reactions are common. Drench the sting with vinegar, then wipe the area with sand or a towel. Don't touch it as you could be stung as well. Get the injured person to a medical facility as soon as possible, especially if he's showing signs of anaphylactic shock, such as having trouble breathing.

If you were planning to head to the Jersey shore or Cape Cod on August 22 and 23, you probably changed your plans. Beaches were closed along the east coast as Hurricane Bill, downgraded by then to a Class I tropical storm, kicked up riptides as it passed.

Riptides, more properly rip currents, are narrow but long bands of water that can pull anything in them quickly out to sea, and they're potentially deadly. The average swimmer or boarder might not recognize a rip current, but lifeguards do. They look for an area of a lighter green color that may be swirling like a washer, or may look like a flat rippling river. Like a river, the rip current's fastest flow is in the middle.

Obviously, the easiest way to avoid a riptide is to stay out of the water. But where's the fun in that? Don't assume you're safe if you're close to shore; rip currents can happen in water that's knee deep. They can also occur when there aren't high wave warnings or beach closures, so you need to know what to do if you're caught in one.

First, don't panic. That's easier said than done, but if you stay calm, you're more likely to survive. Second, don't try to swim against the current. Doing that will wear you out and exhaustion is the cause of most riptide drownings. Relax, tread water and get your bearings. If you can, swim sideways to the edge of the riptide, where the flow lessens and you can probably get to shore. If you see a large wave coming at you, take a deep breath and go under it. If there's an undertow, a frequent companion to riptides, do the same thing: take a quick deep breath before you're pulled under, and relax; you'll pop up again quickly.

Whether the ocean is calm or choppy, be cool in trunks like these Ryan Spooner Hybrid board shorts. Avoid a rash with an Oakley rashguard shirt, and keep your feet from getting too sandy with these sweet Beachcomber Flip Flops by Ed Hardy.

If you're hiking in areas that are part of a wolf pack's territory, will you be attacked by wolves? You're more likely to be attacked by bears or cougars, or even struck by lightning. But a wolf attack isn't impossible, so be prepared.

A group of Norwegian scientists researched wolf attacks in Europe, Asia and North America in 2002, and found that most attacks occurred before the 20th century, and in the past 50 years, there have been only 17 people killed in Europe, and at that time, none in North America. In 2005, a Canadian, walking alone where food dumps from energy development were common, was killed and eaten by four wolves.

There are four possible reasons for wolf attacks. The first, and the probable cause of the Canadian death, is habituation: wolves become accustomed to humans, begin to associate them with food, and lose their fear of humans. Rabies is the second reason, but rabies is rare in North American wolves. The third reason is predation. While a rabid wolf will bite savagely and then move on, a healthy wolf kills and eats its prey. Typically the victims of predation are children and women, and it's more common in Asia than here. The fourth reason is defense. A cornered wolf may bite, but rarely kills.

Stay safe by remaining in a group. Avoid being prey by making lots of noise while hiking and setting up camp. Carry a large backpack to make yourself look larger, and spread out your arms and jacket, if you happen to see a wolf, to look even larger and scarier. Make sure your tent has a lantern because wolves don't like light - but don't shine it directly into their eyes, as that can trigger an attack. For worst case scenarios, carry a mountaineering axe for self defense. Finally, make a fire in front of your tent (if the area isn't under a burn ban) and keep it going all night. Wolves fear fire. Don't feed wolves, or leave food out, and report anyone who does to park or forest rangers.

(Sources: Linnell, J. D. C., R. Andersen, Z. Andersone, L. Balciauskas, J. C. Blanco, L. Boitani, S. Brainerd, U. Breitenmoser, I. Kojola, L. Liberg, J. Løe, H.Okarma, H. C. Pedersen, C. Promberger, K. Sand, E. J. Solberg, H. Valdmann, and P. Wabakken. 2002. The fear of wolves: A review of wolf attacks on humans. Norsk Intitutt for NaturforskningOppdragsmelding: 731:1-65; http://www.wolftrust.org.uk/a-wkp5-linnell-results.html; http://www.wolf.org/wolves/news/2005releases/123005_wolfattack.asp ; http://www.wolftrust.org.uk/faqpeople.html )

A serious fall when you're miles from a medical facility is one of the biggest dangers of back country sports. The worst injury, the one that's impossible to treat where the fall occurs, is a spinal cord injury. As recently as 50 years ago, spinal injuries were almost always fatal, and in the back country they still can be.

Symptoms of spinal cord injuries include pain or a stinging feeling somewhere along the spine; loss of movement of extremities; numbness and/or loss of the ability to feel heat, cold, or touch on a body part; muscle or limb spasms; and difficulty in breathing or coughing. The uninjured individuals may see that the head or another part of the spine is at an unnatural angle.

The first thing you can do is the "ABCD" of emergency medicine: check that the airway is open and the injured person is breathing; check the pulse (circulation), and check for disability (ask if the injured person can move, if he can feel his legs, what hurts, if he knows where he is and who you are, etc.).

If you suspect an injury to any part of the spinal cord, it's absolutely critical that you do not move the injured person at all. Keep his head and spine where they are, and use T-shirts or towels or whatever you have in your packs, or even rocks, to ensure his head and spine can't and don't move. If the individual is conscious, keep talking to him and keep him talking. Put a sleeping bag over him to keep him warm and prevent shock.

If you're able to call out on a cell phone or satellite phone, call for an emergency medical helicopter to fly in for the injured person. If not, then send someone in your group to where the cell phone works, or the nearest medical facility, as quickly as possible, and have them send the chopper. Someone else should stay with him. Don't try to move him; at best, he could be paralyzed for life; at worst, you'll kill him. Stay safe out there.

Driving south from Reno, NV, on US Highway 395, you'll see a foothill that looks like a chunk was torn out of it. The hill is Slide Mountain; a block slide occurred: a single large mass of material gave way and slid downslope. You're more likely to encounter a fall when hiking or climbing, where rocks and boulders detach from a cliff or steep slope and roll downhill.

Landslides can and do happen in all 50 states of the U.S., and kill between 25 and 50 people each year. Major landslides and mudslides have killed hundreds to thousands of people in countries including Mexico, India, and China when slides hit populated villages. If a landslide occurs in the backcountry, it can still kill, but is less likely to if you're prepared.

To survive a landslide, you need to know where they're likely to occur, warning signs and what to do if one happens. Landslides are most common in areas where fires have destroyed ground-gripping vegetation, areas where there's lots of water, from quick snow melt or heavy rains, and areas of volcanic activity - which includes areas around hot springs and steam vents as well as actual volcanoes. Some warning signs are seepages of water in usually dry areas, new fissures in slopes or boulders, or boulders appearing farther apart or closer together.

Your first warning is an increasingly loud rumbling followed by a trickle of rocks falling around you. The rocks will be followed by more and larger material, so get out of the way. Move sideways as far and quickly as possible, then roll yourself into a small ball and hold your pack over your head. If you're the first to notice the fall, shout loudly to your party. Once the fall stops, keep calling out until your group members find each other.

If you're climbing, always wear a helmet. If you're hiking, wear sturdy boots, carry a durable and solid backpack, and carry along a jacket. Even if it's not cold, the jacket can be used to help prevent shock if someone in your party is injured.

"Spelunking" refers to the outdoor activity of exploring caves and caverns, either for fun or research. In the 2003 adventure called The Core, however, a team of specialists take spelunking to the ultimate level by drilling down to the very center of the Earth.

A secret government experiment has caused the planet's molten core to stop its natural rotation, which affects the Earth's electromagnetic field. Without this protective energy layer, people with pacemakers start dropping dead, birds fly off-course and the Sun's rays start burning people and buildings to a crisp.

The quickest way to get the core moving again is by sending a submersible ship through the layers of rock and molten lava and then detonating a series of nuclear warheads. In order to survive the heat, Dr. Ed "Brazz" Brazzleton (*Delroy Lindo*) creates a substance that he calls "unobtanium," which resists extreme temperatures and pressure. The good doctor also has a laser drill capable of drilling through the toughest rock.

In a ship outfitted with Dr. Brazzleton's inventions, the team, led by Commander Robert Iverson (*Bruce Greenwood*), drills through the bottom of the Pacific Ocean. As the first humans to go deep below the surface of the Earth, they see amazing things, such as huge diamonds formed from the tremendous heat and pressure. The deeper they drill, however, the greater the danger becomes.

An entertaining scientific fantasy, The Core takes cave exploration to new depths. It also shows what could theoretically happen if the Earth's electromagnetic field did start to erode. In one early scene, for instance, Major Rebecca Childs (*Hilary Swank*) has to find a safe place to land a space shuttle when magnetic interference wipes out her guidance system.

The Core does get a little grisly at times, showing in graphic detail what happens when unfiltered solar radiation hits the Earth. Even the best sunscreens can't help you when nothing stands between your face and the rays of the Sun.

A fun, but sometimes unbelievable adventure, The Core is one way to heat up a night of movie watching at home.

Most hikers don't consider sandstorms as a potential hazard in the U.S. Sandstorms attack our troops in Iraq, and sweep the Sahara desert; our deserts are hard and dry, not sandy, right? Wrong.

Sandstorms can hit throughout west Texas, Arizona, New Mexico, and into Death Valley. They're caused by a dry wind of almost hurricane strength, which picks up any loose sand, and keeps carrying it as it continues to add more sand to it. In other places this wind has a name. In North Africa, it's the simoom or simoon, while in the Sudan it's the haboob. It doesn't happen often enough in the southwestern U.S. for us to give it a name, but it's one great wind that can move a sand dune to an entirely new place.

Some of the very worst are in Arizona. On July 16, 1971, a sandstorm hit the Tucson area and cut off visibility for miles. Another on July 17, 2007, covered the Phoenix area. Both of these sandstorms caused highway closures. Besides the reduced visibility, the windborne sand and dust can strip the paint from cars and houses - so imagine what it can do to a surprised hiker. In Death Valley, they are frequent and can be deadly. Despite the Arizona July dates, most sandstorms occur in the spring.

When you're hiking in these areas, be sure to wear light hikers for traction and to keep your feet dry, and a cap with a bill to shade your face. If you see a wall of sand headed your way, take whatever shelter you can find, whether it's behind rocks or brush or a hillside (leeward to the wind). If there is no shelter, circle your group and put your backpacks around you on the outside. Cover the top with sleeping bags or groundsheets if you have them, or clothing if you don't.

Keep a little room for air, and don't move until the storm ends. Then dig yourselves off, drink some water, and consider heading for home, you just survived a sandstorm.

When you're headed out to the back country this summer, surviving a vehicle water crash is probably not on your mind. But maybe it should be. The National Highway Traffic Safety Administration reports that 600 people perish each year in the U.S. by drowning inside their vehicles. So if you're route to the trailhead crosses or passes water, be prepared.

The first thing to remember if your vehicle hits water is to stay calm. That's not the easiest thing to do when your car is sinking, but if you don't, you could become a statistic. Unfasten your seatbelt and try to open your door as quickly as possible. If your headlights are on, leave them on; it makes it easier for rescuers to find you and your car.

If the car sinks quickly and water pressure won't let the door open, break a window. Take a deep breath, then kick a window wearing sturdy boots. If that doesn't work, use a heavy flashlight or a large screwdriver that you've stashed in the glove compartment or side pocket (preparation!) and smash the glass. Water will start to pour in but push through it until you're outside your car.

Leave your gear and pack behind, but keep your shades on, because they can protect your eyes from debris in the water. Swim or kick up towards the light. If you've become disoriented, breathe out a little, and watch the bubbles; they'll go up so follow them. Once you break the surface, look around and find the nearest shore, and head to it. Unless you're an expert swimmer trained in water rescue, don't try to save your friend(s). You could all end up in critical condition, especially if the water is cold.

Back on the road, wave down passing cars to get help. Then slow down; your adrenaline rush will have kept you from feeling much pain, and that will probably kick in now. You also need to get warm to avoid shock. The faster you can get help, the more likely that you and anyone still in the car will survive.

Summer's here, and for many it's time to hit the beach and get in the water. Whether you're diving, surfing, or just swimming, it's possible you'll be attacked by a shark. Experts from NOVA estimate there are 100 shark attacks annually, with 25 to 30 shark-related fatalities. That may not sound like many unless you're being bumped in the water by something you can't see.

The best way to survive a shark attack is prevention. Pay attention to warnings. If beaches have signs that there are sharks, choose another place. Never swim, surf, water-ski, or boat alone. Always have at least one person with you, and at least one in the boat. If you're in waters known to have sharks, don't swim during sunrise and sunset, or after dark.

Wear dark solid clothes, like this mens swimsuit by Speedo; include a dark top if you need one. Ladies, you can wear black and still look sexy; this suit by Carve Designs Palm Beach has a removable halter, so you can tan with no shoulder stripes. Sharks don't see very well, and bright colors, patterns and shiny jewelry look like fish fins or scales to them. If you see a shark, shout, and get out of the water. Stay out of the water if you have an open wound. Sharks can smell blood, and it smells like dinner. Obviously, don't provoke a shark.

If a shark does attack you, and you can't get away, stay close to your buddy and try to look big. Sharks understand the food chain; if you look like trouble, they'll back off. Keep your back against a reef or wall so the shark has fewer attack angles. If it bites, fight back with your camera or air tank or fists. Go for the nose, eyes, and gills, the most sensitive spots for sharks.

Chances are you won't see a shark this summer, but if you do, remember these tips, and stay calm, and you'll be a survivor.

(Sources: http://www.qualityhealth.com/health-lifestyle-articles/how-survive-shark-attack
http://in.reuters.com/article/environmentNews/idINTRE50F20Q20090116
http://adventure/howstuffworks.com/15-tips-for-surviving-a-shark-attack.htm )

Tornadoes are one of nature's most deadly acts. While they're most common in tornado alley -- the area from just into the southeast to Texas and north, up the Great Plains -- tornadoes can strike almost anywhere, and have struck in almost every state in the lower 48, as well as Canada and Mexico. With tornadoes, it's not just the wind, but also the debris that wind is carrying, that can be a major danger. It takes some planning to survive one outdoors.

Before you start your hiking trip, check the weather. A tornado "watch" means it's possible there will be a tornado; a tornado "warning" means a tornado has been spotted, so if you haven't left yet, go to your basement or an interior room. If you head out during a tornado watch, take a battery-operated radio with you, along with a good flashlight and a rain jacket, and watch the sky. Before a tornado, the sky turns dark, the light takes on an unnatural greenish-yellow color, and you may hear a sound like a freight train.

If the sky changes, or funnel clouds begin to drop from black clouds, you need to get to some kind of shelter immediately. Don't take shelter under a bridge or trees; they won't protect you from flying debris or hail. If there are no buildings nearby, look for the lowest place you can find. It might be a ditch, and if you're very lucky, you might find a culvert. Hunker down in that low spot, put your arms over your head for protection, and stay as close to the ground as you can. Keep your backpack on and securely fastened, as it can help protect you from debris.
hiking
Once the tornado has passed, listen to your radio again. If the danger is past, head for home or make a camp. If there's still danger, use the time you have to find a better safe spot, like a cave, ditch, or culvert. You may be bruised, but if you stay flat, you'll survive the worst that nature can throw at you.

(Sources: http://www.fema.gov/hazard/tornado/index.shtm , http://www.insure.com/articles/homeinsurance/tornado-tips.html , http://www.outdoorlife.com/photos/gallery/survival/warm-weather/2009/04/tornado-survival-tips)

Quicksand and sinkholes. Many hikers and climbers think those are movie props, and while the way they're used in movies doesn't match reality, they are out there, and you need to be prepared for them.

You can find quicksand, liquified soil or sand, nearly anywhere that water meets sand, including ponds, marshes, sloughs, beaches and river deltas. It's found in places as diverse as New Jersey and North Carolina, but it's most common in Florida. You could encounter it in any marshy area after a heavy rain.

Natural sinkholes are found in karst, land where the bedrock is limestone, salt beds, or any rock easily dissolved by water. Again, most are in Florida, though you'll also find them in Texas, Kentucky, Missouri or anywhere limestone lies beneath the soil. They can appear very suddenly; Lake Jackson in Florida took only a few days to completely disappear into a sinkhole in 1999. The beautiful "blue hole" off the coast of Belize is an underwater sinkhole.

Sinkholes can also be caused by people. They're common in areas with underground mining, whether of coal, like that in Pennsylvania, or of gold, as in parts of Nevada. When the burden of soil and vegetation becomes too heavy over the tunnels, it caves in and becomes a sinkhole.

Your best approach is to avoid them. Use a walking stick or trekking poles to test the ground ahead of you in swampy areas. If it slides down, you just found quicksand. If you're unfortunate enough to fall in, don't panic; you'll float on quicksand. Relax, lie back, and let your trekking partners pull you out, either with the poles or climbing rope carried in a rope pack.

If you're caving, you should already have a helmet and a headlamp. The danger from sinkholes is both below you and above you; you could fall in, or the rock above you could collapse. Test the ground ahead of you and the rock above you. If your pole can go in, it's time for you to get out.

Pay attention and watch where you walk, and you'll survive quicksand and sinkholes!

Summer hiking in mountain ranges is often threatened by afternoon rain. Those showers can become thunderstorms with dangerous lightning. Whether you're on a day hike or a back-packing camping trip, be prepared to survive thunderstorms.

Although the odds of being struck by lightning aren't high, it's still a possibility. Stay aware of the weather around you. If clouds start to build up, study them. Are they just rain clouds, or are they turning into tall black storm clouds that bring thunder and lighting along with rain? If those clouds are moving in your direction, find a shelter. And remember, lightning can strike well outside the area of rain.

Tents aren't the best shelters in a thunderstorm. If your camp is in an open area, your tent is probably the highest structure, and the most likely to be hit by lightning. If your tent is under trees, you're safer, but still at risk both from lightning hitting the trees around you and from ground currents. If you're in your tent, don't lie down; instead, be a small target: pull your knees up to your chest, put your head down, and wrap your arms around your head.

If you're hiking, look for the lowest area you can before the storm arrives. Consider building a shelter of brush at the base of a rock face, and covering it with a tarp. No time to make a shelter? Drop your pack, and make yourself a small target.

Pack for rain as well. A flashlight and a battery-operated radio are musts; also, carry a lightweight tarp or rain cloth. Pack a light-weight rain jacket with a hood, and wear lightweight boots. Carry a first aid kit too, in case someone is injured. If someone in your group is actually struck by lightning, their heart may stop; use CPR to get their heart and lungs working again, and get them to a medical facility as soon as possible. Your first aid kit should have burn ointment and bandages if there are burns as well.

If the forecast is for severe thunderstorms, then put off your hike, or stay with your car. FEMA's general rule for safety is that 30 minutes after you hear the last thunder, it's safe to leave your shelter and head on, or head home.

(Source: http://fema.gov/hazard/thunderstorm/index.shtm )

Planning a long back-packing trip, and intend to supplement the food you carry with food you find? You'd better be certain that you know what you can eat, and what to avoid if you want to make it home.

In the mountains, the desert, or the grasslands, you can find edible plants. Some basic rules are not to choose anything with fungus or mildew, or that looks spoiled. If you've got a sensitive stomach, you may want to avoid wild greens. Know the plants must be cooked before you eat them, like those containing oxalate crystals, which can damage your kidneys. Finally, avoid plants you don't recognize if their sap is milky or off-color; if they have beans, bulbs, or seeds inside pods; a bitter or soapy taste; thorns, hairs, or spikes; plants that look like foliage from dill, carrot, or parsley; if the woody parts and leaves have an almond scent; if they have pink, purple, or black spurs on grass heads; or if they have three-leaf clusters.

Many berries are edible, including blueberries, blackberries, raspberries, gooseberries and huckleberries; others, including daphne berries, jasmine berries, lantana camara berries, yew berries, moonseed berries and mistletoe berries, are fatal. Edible root plants include agave root, cammas bulbs, squaw root, wild carrots, Indian Cucumber root, wild onion, and wild garlic. Don't confuse them with flower bulbs, or candelabra cactus root. Greens are an excellent supplement to your wild diet. Dandelion greens, chickweed, clover, lamb's quarters, milkweed, and mustard greens are all good choices as well. Avoid anything that looks like dill or parsley, because it could be nightshade or hemlock.

Some plants are prepared to improve their taste; bitter greens can be soaked, acorns leached in water, and stems, leaves and buds of other plants boiled until they no longer taste bitter. Tubers, roots, and cattails should be boiled, baked, or roasted. That removes any oxalates some roots may have. Early grains can be eaten raw; once they're hard, you can grind them into flour or boil them for soup. The sap from birches and sycamores provides a sweetener like maple syrup.

Of course to do all this, you need some gear. Start with a multi-purpose tool to cut or dig up plants. You'll need cookware to cook things in, and a stove to cook on. And of course, a big backpack to carry it all.

Be careful, and bon appetit!

(Sources: http://plantanswers.tamu.edu/publications/poison/poison.html , http://www.wilderness-survival.net/plants-1.php, http://www.wildwoodsurvival.com/survival/food/edibleplants/ , http://www.essortment.com/all/ediblewildplan_repo.htm )

From early spring to late fall, a danger in your wilderness adventure is insects. While most insect bites aren't deadly, a mass attack, or a sting you're allergic to, could cause serious health issues.

If you're hiking in areas where there are pools of standing water or swamps, you'll encounter mosquitoes. Mosquito bites aren't just itchy; they can also give you West Nile virus. Wearing a long-sleeved shirt like this one with an SPF of 30 for sun protection, and long pants that can convert to shorts, or these that also provide sun protection, to limit the skin mosquitoes and other insects can reach. You'll also need a serious insect repellent. Health authorities in Utah recommend DEET.

Another enemy is the Africanized Honey bee, more commonly called the "killer bee." Unlike other honey bees, these are aggressive and easily provoked. Killer bees can sense you from 50 feet away and will chase you for at least a quarter mile. You'll receive at least ten times as many stings as you'd get from other bees. The stings aren't often deadly, just painful. Wasps, like bees, attack in swarms. If you're attacked, run away, and cover your face and head, as killer bees and wasps most often sting there. Don't take cover under water, because the bees will wait there for you to come up and breathe.

A third type of pest is the tick. Inhabiting both woods and grassy areas, they attach themselves to your skin. Again, the danger is less the bite than the Lyme disease it can carry. Check for ticks frequently.

If you're stung by a bee or wasp, scrape the stingers out using your nails. Use the tick remover forceps from your first aid kit to remove the entire tick; grab it as near as possible to your skin, and pull it out slowly but firmly. Make sure you get the head of the tick as well as the body. If the bites itch badly, use an anti-histamine cream or liquid. If you or someone in your group is allergic to bee stings, be sure that they carry epinephrine to use if they go into anaphylactic shock. If you start feeling flu-like symptoms or develop a rash after a tick bite, see a doctor as soon as possible, because it could be Lyme disease.

Educated and prepared, you can survive insect bites and enjoy your trek.

(Sources: http://www.utsouthwestern.edu/utsw/cda/dept16498/files/182660.html, http://irreference.com/how-to-survive-if-you-hit-a-beehive/,http://www.tucsonweekly.com/tw/07-04-96/outthere.htm , http://www.columbia.edu/itc/cerc/danoff-burg/invasion_bio/inv_spp_summ/Apis_mellifera_scutellata.htm, http://quamut.com/quamut/how_to_survive_an_animal_attack/page/how_to_avoid_ticks_and_treat_tick_bites.html )

From early spring to late fall, your wilderness adventure can bring you into contact with poisonous plants. Whether it's poison ivy east of the Rockies, poison oak west of the Rockies, or poison sumac in the humid wet areas of the southeast, plants across the country are just waiting to give you a rash.

The first step in prevention is learning to recognize the plants. Poison ivy is a low-growing plant, a vine, or a shrub. The leaves can be either smooth-edged or notch-edged, and they're usually in groups of three. Poison oak is nearly always a small bush, but can also be a vine. Its smooth-edged leaves can be in groups of three, five or seven. Poison sumac is either a small tree or shrub. It's pretty leaves have nine to thirteen leaflets on a red stem, and flowers that become small white fruit. All of them irritate the skin.

Since it's hard to recognize them, and since their foliage is usually combined with other concealing foliage, the second preventive step is to dress for avoidance, although this may be uncomfortable in warm temperatures. A long-sleeved shirt, long pants (these are convertibles), high-cut boots, and long socks can help protect your body, but only gloves can save your hands.

These plants produce a oil or resin called urushiol that causes an allergic reaction when it touches the skin of about half the population. The oil can stick to your clothing, your pack, and even your pets and you can get the rash from touching anything that still has the oil. When you get home, thoroughly wash everything.

If you think you touched it, wash your hands immediately, using soap. The rash usually takes between 24 to 72 hours to develop, but for the 15% of the allergic population who are severely allergic, it can start as soon as 4 to 12 hours. In this case, urgent medical care is necessary, as it can become anaphylactic shock.

If you get the rash, you can treat it with oral antihistamines, which you should carry in your first aid kit, calamine lotion, and/or an antihistamine cream or cortisone cream. A cool damp compress helps soothe the rash, which generally goes away on its own in two to three weeks. If the rash is very severe, see a doctor for a prescription steroid, and take it long enough to completely cure the rash.

(Sources: http://www.medicinenet.com/script/main/art.asp?articlekey=82545 , http://www.duke.edu/~cwcook/trees/tove.html, http://www.emedicinehealth.com/allergy_poison_ivy_oak_and_sumac/article_em.htm )