A flax field is a location where many flax plants are located together. Each of these spots has a random number of flax, and a flax spot disappears when all the flax in that spot is picked. They reappear later after approximately 5 seconds in the same spot. They can be picked by members, granting 1 Farming experience, and may then be spun into bow strings. This gives 15 Crafting experience.
Currently, there are five flax fields located in Gielinor.
The first flax field is an area next to the beehives where the player can pick flax. There is also a building with a spinning wheel to the west where players can spin the flax into bow strings. It is just south of Seers' Village and west of Catherby. It is a popular area with players picking flax as an early temporary moneymaker as flax can sell for about 22 coins each. After completing the Seers' Village Tasks Geoffrey will collect flax for you when wearing a Seers' headband.
There is also a second flax field in the Elven town, Lletya. It contains less flax than the location at Seers' Village, but this flax field lies closest to a bank. Players need to have the quest Regicide done to pick flax here.
A third flax field that can be found in the south-east region of the Tree Gnome Stronghold, it contains lots of flax spread throughout the area. Spinning wheels can be found nearby. A bank can also be found north-west of the area.
Some flax herbs can be found on Lunar Island, it contains a low amount of flax, and it is spread out over the south part of the island, on the way from the city to the Astral Altar.
A fifth flax field exists in Taverley. It's small and contains a low amount of flax which makes it quite impractical.