I'm glad she is safe! To get sticker burrs out of dog hair you use an oil..I like coconut oil. Put it on thick, then comb through the hairs with a metal or wide tooth comb.She is home! I went and looked out my back door as soon as the sun started coming up. And she was sitting far out on my hill right outside the tree line!! Poor baby is soak and wet due to the rain, and full of sticker burrs though! I'm not sure on how to get then out.
This might work on feathers too.
And as @sourland said keep an eye out. Something must have frightened her.