Water
Build a three-layer ground filter
A field filter clears silt and cuts pathogens — it doesn't replace boiling.
Clay Hayes — Charcoal & Sand Filters
Step-by-step
Cut the bottom off a bottle (or use a bark cone) and invert it over a catch vessel.
Bottom layer: coarse pebbles, two fingers deep.
Middle layer: clean sand, three fingers deep.
Top layer: crushed charcoal from your fire, three fingers deep.
Pour cloudy water in slowly; the first pass may run dirty — recycle until clear.
Boil the filtered output before drinking.
Warning: Charcoal only — never ash. Ash makes the water caustic.
Related outdoor skills
Educational reference only. Wilderness conditions change fast — practice in low-stakes settings, take a certified wilderness first-aid course, and confirm regional regulations before you rely on any of these skills in the field.