The photographs here only hint at what her portrayal is like, so I'll try to sketch in a few additional details:   

First of all, there's a possibility that you might wander past the Dryad  without even noticing.  I saw a number of distracted adults do just that, though children seemed aware of her presence immediately.  Her costume is of course perfect for becoming lost against bluish oak trunks, the greens and oranges of lily beds, and the sun-dappled grays of stone and pathway, and, like any elemental worth her salt, she uses her camouflage to its best advantage, striking and holding oddly graceful poses so that she quickly merges with her natural surroundings.   

Then there's the manner in which she does move, when she chooses to do so.  When I came upon the Dryad mid-afternoon, she was on the edge of a bed of orange lilies, her expression fixed in a gentle smile, brown eyes motionless.  She radiated the same sense of quiet presence in the midst of the bustle of the Faire as the flowers did themselves--so much so, that it almost seemed as though she might be an inhabitant of some slower-moving time stream.  When she moved, there was an oddly disjointed quality to it.  The eyes might move first, then a hand a moment later, then an arm, then the body, until all these separate events at last resolved into a new position.   The effect was remarkable.  

Equally remarkable was the effect she had on small children.  I was watching a little girl--perhaps four years old--at the instant she first noticed the Dryad.   There was an initial look of surprise.  She then stood staring, as motionless as the Dyad herself, trying to figure out just what it was she was looking at.  Clearly it was real, but...  At that moment the Dryad's hand moved.  The ball of vine she carries rolled across the path, stopping directly in front of the little girl, whose eyes were wide and whose mouth was slightly open in surprise.  There was a long moment of silence as they regarded each other.  Then the Dryad tilted her head slightly in an inquiry, and rotated her hand so that her palm was up.  The little girl rolled the ball back and the Dryad caught it.  I only wish I'd had my camera ready, so I could have caught the look of absolute delight that lit up the kid's face.