Raffia binding simply holds the branch fibres together while bending so reduces the chances of a bad break. Even when the branch breaks a little the bark and underlying structure is held together so healing is quicker and scar swelling reduced.
Not particularly used to prevent wire marks though it may help a little. However if left in place too long the tree can swell up above and below the binding which can be far worse than a few wire marks so make regular checks and remove the raffia at the first signs of bulging above or below. Length of time will depend how fast the tree is growing and thickening. Probably a year, sometimes less. The bend may not even be set properly but the fibres will have changed shape so normal methods can hold the bend without damage after the raffia is removed.
Raffia can be used on any species but normally used more often on conifers as they are the trees we usually make more extreme bends in. Broadleaf species tend to be far more brittle and even raffia won't stop a maple branch snapping completely. Come to that, it only reduces the chance of catastrophic damage in conifers too. Still need to read the tree and listen to be able to tell when you've gone far enough.
Soak raffia for around 30 min or longer (overnight is good). Warm water helps water to penetrate faster and better and can be more comfortable to work with.
Tie 6-10 strands together and use the bunch to wrap the area. You'd be there all week trying to wrap with 1 strand at a time. feed in extra bunches before the first length runs out so the new fibres are held in place by the last few wraps of the first length and the ends of the forst ones are held by the new length. Easier to show than to write.
