The Seer's Village flax field.
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 bowstrings. This gives 15 Crafting experience.
Currently, there are seven flax fields located in Gielinor.
Taverley
There is a small flax field in Taverley, north-west of the lodestone. It is located near a Compost Bin, making it a good source for compostable material.
Seers' Village
There is a flax field south of Seers' Village and west of Catherby, next to the beehive field. It is a convenient place to pick flax as there is a spinning wheel in a building to the west. It is a popular area with players picking flax as an early temporary moneymaker as flax can sell for about 96 coins each. After completing the Seers' Village Tasks, Geoffrey will give out a set amount of flax daily, depending upon the level of Seer's headband owned.
Lletya
There is a flax field in Lleyta in Isafdar. It is located south of the Lleytan bank. It contains less flax but is considerably closer to a bank than most other fields. Mourning's End Part I is required to gain access to this field.
Tree Gnome Stronghold
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.
Lunar Isle
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.
Rellekka
Some flax plants cam be found south of Rellekka, near the Fenris wolves.
Prifddinas
A sixth flax field can be found in the Cadarn Clan section of Prifddinas, just north of the max guild. It is situated directly west of a spinning wheel, making it a good place to spin bowstrings.