From the very worst to the most stinky, here are five things you want to avoid at all costs and what to do if you get into them:

Rat­tlesnakes
Despite what you’ve heard, rat­tlesnakes rarely attack unpro­voked. In fact, they’re pret­ty docile. They rat­tle when they’re scared; it’s their way of telling you to back off. Of course, if you acci­den­tal­ly star­tle one (like step­ping on it), it’s high­ly like­ly they’ll bite. But keep in mind that approx­i­mate­ly one-third of all rat­tlesnake bites are “dry bites,” which means no ven­om is inject­ed. Con­sid­er those bites a warn­ing. Now, poke them hard with a stick or try to shoot at one, and you’re like­ly to end up face to face with a pro­voked and pissed off the snake that will almost cer­tain­ly unload a lot of ven­om, and also strike sev­er­al times. The one to real­ly watch out for: the Mojave green rat­tlesnake, which releas­es the most tox­ic ven­om of all the rat­tlers in the U.S. 

What to do: The best way to avoid get­ting bit in the back­coun­try is to stick to trails (rat­tlers will avoid areas where humans fre­quent) and watch where you put your hands and feet, espe­cial­ly on trails at night or near piles of rocks dur­ing day­light (they often sun them­selves on rock ledges or hide out under them).  Rat­tlesnakes tend to avoid wide-open spaces because the expo­sure makes them more vul­ner­a­ble to preda­tors, and won’t pur­pose­ly strike just because they sense you. But should you get bit, go ahead and scream (get the fear out of your sys­tem because soon you will have to make some deci­sions). Once you’ve let off this pri­mal steam, take a breath and try to be calm. If you have a bot­tle of water (as you should), hit the wound with a heavy stream, and drink some of it, too. If you are near an urgent care cen­ter (and a cell tow­er), call an ambu­lance or have some­one take you there. Do not apply ice or cold packs to the bite, and keep the area bit below your heart. Just in case you’re a vic­tim of one of that 25% of ven­omous bites, you’ll need to get mov­ing toward treatment.

If you’re in the mid­dle of nowhere, you’ll, unfor­tu­nate­ly, need to chill a bit. After you calm down, rest for 20 to 30 min­utes to encour­age the ven­om to local­ize at the site of the bite. Then get up and slow­ly hike out; overex­er­tion can stim­u­late ven­om spread­ing. Suc­tion­ing sel­dom helps, but if you have a ven­om suc­tion kit and some­one to apply it, give it a try after allow­ing the ven­om to local­ize. NEVER try to suck it out my mouth. Also, don’t tie a tourni­quet on the limb on which the bite is locat­ed. Also, take note: if you don’t feel severe con­tin­u­al throb­bing pain at the wound, there’s a like­li­hood the bite is non-ven­omous. Remem­ber, most rat­tlesnake fatal­i­ties result from a pro­voked rep­tile. If it was an acci­den­tal encounter, you may have only got­ten that prover­bial warning.

Note: All this advice was culled from Brady’s Emer­gency Care for the Sick and Injured, the stan­dard train­ing and pro­ce­dures man­u­al for Emer­gency Med­ical Technicians.

Three-Leafed Plants
Poi­son Oak, Poi­son Ivy, Poi­son Sumac. Leaves of three, beware of me. All of these infu­ri­at­ing botan­i­cals, with no appar­ent excuse for exis­tence, excrete an oil called urush­i­ol. It’s in the leaves, the stems and the roots—even when it’s dead. When this oil comes into con­tact with skin, cloth­ing or socks, it’s quick­ly absorbed (and can remain indef­i­nite­ly on cloth­ing and footwear and even the han­dles of a trekking pole). It can also end up in your dog’s fur and be passed to you that way. Strange­ly, it’s usu­al­ly not the first encounter that’s the worse; increased sen­si­tiv­i­ty to urush­i­ol devel­ops from repeat­ed exposure.

No mat­ter, con­tact with any of these can pro­duce the most intense itch you’ve ever expe­ri­enced. Thank­ful­ly, itch­ing it won’t spread the oil since it’s imme­di­ate­ly absorbed into the skin, but it could lead to infec­tion. So be care­ful. Blis­ters typ­i­cal­ly appear 12 to 72 hours after con­tact, and the skin begins to hard­en into a leath­ery patch with­in a few weeks. Some peo­ple also expe­ri­ence a sys­temic inflam­ma­to­ry reac­tion that caus­es joint pain and even trou­ble breath­ing. In either case, expect to lose a lot of sleep while you wake to repeat­ed and invol­un­tary bouts of relent­less scratching.

What to do: If you know what it looks like (look these herbs up and mem­o­rize them) and can find jew­el­weed or gumweed (Grindelia) near the poi­so­nous plant, pick it and crush it, and imme­di­ate­ly apply it to the spot that came into con­tact with your skin. As soon as you can, wash the spot with a grease-cut­ting soap (add lemon juice to your usu­al dish soap). Then use a com­press of either cof­fee (which con­tains anti-inflam­ma­to­ry chloro­genic acid) or witch hazel. Fol­low that—before the blis­ters have a chance to erupt—with a gumweed or jew­el­weed tinc­ture. Both are remark­ably fast and effec­tive at stop­ping a rash or blis­ters from ever erupt­ing. If you’re past that point and are already blis­ter­ing, apply one of the tinc­tures and then try plas­ters made with rhubarb stem, bak­ing pow­der, sal­i­cylic acid (smashed aspirins), calamine (a zinc and iron blend) or col­loidal oat­meal. Repeat as needed.

Ticks
What real­ly needs to be said about this worth­less insect? They live in forests and grass­lands, and in ole­an­der bush­es in desert land­scapes. In any case, they can be more than a nui­sance. If you get nailed, keep an eye out for tick-borne dis­eases. They will pro­duce symp­toms that include swollen lymph nodes, fever, weak­ness, headache, stiff neck, mus­cle or joint aches and a rash. Ticks car­ry­ing Lyme dis­ease will leave behind a red spot (tar­get) with an expand­ing con­cen­tric red ring around it where ever they feed on your body. Ticks car­ry­ing Rocky Moun­tain spot­ted fever leave behind small red bumps (which will show up on the wrists and ankles). Texas Lone Star tick bites can even leave you aller­gic to most meat for life (alpha-gal aller­gy). When a per­son with the alpha-gal anti­body eats mam­malian meat, the meat trig­gers a severe release of histamine.

What to do: If you should end up with a tick on you, remove it. There are dozens of ways to do this—a quick inter­net search will show you, but a good one is to pour tea tree oil or cook­ing oil over it. As the oil begins to smoth­er the bug­ger, it will begin to back up and extract itself; use a pair of tweez­ers to help it along, hope­ful­ly, head intact. Thor­ough­ly clean the area where it bur­rowed in, and place a drop of tea tree oil on that spot to pre­vent infec­tion. If you start to swell, feel deep pain, have dif­fi­cul­ty breath­ing or expe­ri­ence unco­or­di­nat­ed move­ments and gen­er­al weak­ness after a bite, you may be hav­ing an aller­gic reac­tion. Get to a doc­tor imme­di­ate­ly. No mat­ter what, after a bite, the tick should be sealed in a jar and deliv­ered to your doc­tor’s clin­ic to deter­mine whether it is car­ry­ing a disease.

Sting­ing Nettle
A pro­lif­ic peren­ni­al plant that has been used as food and med­i­cine for cen­turies, sting­ing net­tles are par­tic­u­lar­ly ben­e­fi­cial for com­bat­ting sea­son­al aller­gies when tak­en as an herbal sup­ple­ment. But in its nat­ur­al state, the herb has hairs called tri­chomes lin­ing its leaves and stems that are high­ly irri­tat­ing to pests and preda­tors, and bare human skin. The result­ing inflam­ma­to­ry reac­tion that results from con­tact can pro­duce a tem­po­rary burn­ing “pins and nee­dles” like sensation.

What to do: If you brush up against this plant and hap­pen to be car­ry­ing a water bot­tle, imme­di­ate­ly flush your flesh with water. No water? Use sali­va (which con­tain net­tle-bust­ing enzymes). Spit and rub. Oth­er­wise, look around for cer­tain plants that typ­i­cal­ly grow near net­tle, includ­ing dock leaf, broadleaf plan­tain, spot­ted jew­el­weed or gumweed (slice the stems and rub on your skin), and ferns (rub the spore side of the fern on your skin). Oth­er top­i­cal reme­dies, once you arrive back home, include a paste of bak­ing soda and water, or apply cor­ti­sone cream, calamine lotion or milk of mag­ne­sia. But try wash­ing it first with soap and water before apply­ing top­i­cals. Usu­al­ly, that will take care of it.

Note: If you’re aller­gic to bees you may be aller­gic to sting­ing net­tles. Left untreat­ed, a severe inflam­ma­to­ry reac­tion could lead to ana­phy­lax­is, which can be fatal.

Skunks
Accord­ing to the Mayo Clin­ic, skunks are among the most com­mon car­ri­ers of rabies, but it’s rare to get close enough to wor­ry about that. A big­ger con­cern is the putrid smell that will stick to you or your dog like none oth­er. It’s how they defend them­selves. While it’s fair­ly easy for humans to avoid get­ting sprayed, our canine com­pan­ion’s curios­i­ty and preda­tor dri­ve can also be their worst enemy.

What to do: Keep your pet out­doors and get some­one to run to the store for rub­ber gloves, a bot­tle of enzymes (pet stain and odor remover), a cou­ple bot­tles of hydro­gen per­ox­ide (H2O2), a box of bak­ing soda and some dish­wash­ing or laun­dry soap. Mix a quart of the H2O2, a half-cup of bak­ing soda, a cou­ple of tea­spoons of dish soap and a half-cup of enzymes in a buck­et and stir. Put on the rub­ber gloves and begin rub­bing the works into a lath­er on your dog’s fur. Work it in, then hang on to your dog so he doesn’t shake it all off, and let the ingre­di­ents do their job break­ing down the skunk oil. Rinse thor­ough­ly and repeat as need­ed. The same ingre­di­ent blend works well on humans too, thankfully.