The first Dryads came to Nevarost through a portal established by a Fey Lord who was madly in love with a nevarostian. Eventually, the nevarostian moved to the Feywild with the Fey Lord, who then closed the portal, leaving the Dryads stranded on that new, magical land. They quickly built a garden, called the Great Arbor, where their trees could be safe from lumberjacks and humanoids that wished them harm. Though most Dryads are happy to stay away from their humanoid neighbors, it's not terribly uncommon to see members of their society wandering out into the the lands.
The Great Arbor
Protected by a multitude of enchantments, the Great Arbor is both the womb and the home of the dryads. There, the trees from which they sprung to life are guarded. Not all dryads are bound to this place, however. Those of them that commit great crimes against their own kind have their trees moved out, as a sign of their banishment. Furthermore, dryads may elect to have their trees moved out voluntarily, though none have done so in living memory. Among the enchantments protecting the place, the most famous is one that erases the Great Arbor's location from a Dryad's memory once they leave, so that they won't be able to reveal it to outsiders who would bring in harm. This means that, even if a Dryad wishes to go back home after visiting the outside world, it is extremely hard to do so. It's not uncommon to see them banding once away from the Great Arbor, trying to get back home together.
A Breath of Life
There's two ways a dryad is born. Through their love for another humanoid, or when a humanoid finds the Great Arbor and asks to join them. In the first case, when a dryad and a humanoid decide to have a child, a fruit sprouts on a branch, in the dryads tree. Eventually, the fruit falls down, and from it's seeds a sapling is born, and bound to it, a child dryad. Dryads born inside the Great Arbor are taken care of by the community, and rarely come to know their parents.
In the second case, if someone finds the Great Arbor by accident, they are given the choice to either forget they were ever there, or to be turned into a dryad, via a secret ritual. Not much is known about this, however, and some scholars don't believe to be true at all.
Ability Score Increase. Your Charisma or Wisdom increase by 1.
Age. Though they're one of the newest races to appear in Nevarost, their oldest members still alive are documented to be more than 500 years old, and they're considered to have reached adulthood at around 10 years. Their lives are, however, tied to the trees they were born out of, and if the tree is destroyed, then a dryad will go through great pain and generally die. There's no record of a dryad surviving this.
Alignment. Dryads that lived most of their lives among other dryads tend towards a Neutral stance on things, mainly interested in keeping to the nature around themselves.
Languages. Dryads speak Common and Sylvan.
Of the Land. Thanks to your personal connection to nature, you gain proficiency in either Nature or Survival skills.
Fey Ancestry. You have advantage on Saving Throws against being Charmed, and magic can’t put you to sleep.
Subrace. Three main subraces of Dryads populate Nevarost, the Oaks, the Leaflings, and the Ferns.
Ability Score Increase. Your Strength score increases by 2.
Size. Oak Dryads are usually bigger and thicker than a normal sized humanoid, going well over 6 feet tall. Your size counts as Medium.
Speed. Your speed is 30ft.
Oaken Skin. As a reaction, you gain resistance to non-magical Bludgeoning, Piercing, and Slashing damage until your next turn. Once you do this, you can't do so again until you finish a long rest.
Ability Score Increase. Your Dexterity score increases by 2.
Size. More akin to gnomes and halflings than to the other humanoids, leaflings stand between 3 and 4 feet tall. Your size counts as Small.
Speed. Your speed is 25ft.
Tree Hop. Once on her turn, the Dryad can use 10ft of movement to step magically into one living tree within her reach, and emerge from a a second living tree within 60ft of the first tree, appearing in an unoccupied space within 5ft of the second tree. If there is no unoccopied space withing 5ft of the second tree, the Dryad can't exit through that tree. Both trees must be Medium or bigger. Once you use this ability, you can't do so again until you finish a short rest.
Ability Score Increase. Your Charisma and Wisdom scores increases by 1.
Size. Fern Dryad can go from 5 to 6 feet tall. Your size counts as Medium.
Speed. Your speed is 30ft.
Bloom Magic. You know the druidcraft cantrip. When you reach 3rd level, you can cast entangle once every long rest. At 5th level, you can cast spike growth once every long rest. Charisma is your spellcasting ability for these spells.