The hover over tooltip for Enchant states “adds one-third fire damage to ranged weapons”, this isn’t true. Ranged weapons receive the entire fire damage bonus.
https://cdn.discordapp.com/attachments/900949574095634512/999193687378632807/unknown.png
Take a level 4 enchant from a level 26 Act 3 merc for example. The tooltip suggests ranged attacks would only receive 4-5 fire damage, in reality they still receive the full 12-17 fire damage.
http://theamazonbasin.com/wiki/index.php/Enchant
Despite what the skill tree description says, fire damage added by Enchant is not reduced to 1/3 when applied by a ranged attack.