Whether you plan to hike for a few hours or many days, you have to think about food and water when you'll be on the Pacific Crest Trail, and re-supplying if you'll be doing a long-distance hike. Day hikers can easily carry snacks on them for sustenance, and even those heading out for several days can easily carry all of their food on them. But if you plan to be hiking a few weeks or months, or thru-hiking, you'll need a food strategy.
Traditionally, long-distance hikers have mailed boxes of food to themselves to post offices in select towns along the route before they even start the trail. Then, when they reach each town, they replenish their food supplies. Others send just one box to the first town. When they arrive, they take the contents for their next stretch, then purchase more food in that town, refill the box and mail it to the next stop. Both of these methods work reasonably well, but they still pose several problems. Mailing food is expensive, for one. And what if you've packed numerous boxes of a certain kind of food that you end up hating partway through your hike, or that doesn't work well with your system? Or, what if you reach a town ahead of schedule and your box hasn't arrived yet, or you decide to skip a section? Increasingly, hikers are ditching the boxes and instead buying food in the towns along the way instead, or using some combination of both methods [source: Pacific Crest Trail]. But check out the stores ahead of time -- not every stop has "backpacking" food that's lightweight, full of calories and nutrients and that won't spoil in your pack. The following towns along the trail have full grocery stores, rather than just gas stations, where you can resupply: El Cajon, Idyllwild, Big Bear, Aqua Dulce, Tehachapi, Kennedy Meadows, Mammoth Lakes, South Lake Tahoe, Sierra City, Chester, Burney, Mount Shasta, Etna, Ashland and White Pass.
And then there's water. Water is always an issue on the PCT, whether you're hiking a day or more. There are long stretches without any water available -- the longest is 35.5 miles (57 kilometers) north of Tehachapi in the northern part of Southern California -- and you have to be prepared for emergencies as well [source: Pacific Crest Trail]. Grab a guidebook that lists all known water sources so you know how much to carry (most have this information). But in general, water is scarce in Southern California, and alternates between being plentiful and scarce in Northern California and Oregon [source: Pacific Crest Trail].
Even where water is plentiful -- Central California, Washington and parts of Northern California and Oregon -- boiling, treating or filtering it before drinking is essential, as many water sources are contaminated by pesticides, herbicides, fertilizers and organic parasites like Giardia lamblia and Cryptosporidium. If you plan to use a water filter or purifier, make sure it's effective against Giardia and bacteria. It helps if your device is also effective against Cryptosporidiosis and viruses. The most popular chemical water treatment is iodine, normally dissolvable tablets. Newer products made with stabilized chlorine dioxide are also gaining traction [source: Pacific Crest Trail].