ΔE 8.7, close: similar, with a visible difference side by side. Ink Black Green is more saturated than Dryad Bark. They are different kinds of paint: Citadel Dryad Bark is an opaque base/layer paint and Vallejo Ink Black Green is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Ink Black Green is more saturated than Dryad Bark. They are different kinds of paint.
The same difference applies the other way round: Dryad Bark is more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Dryad Bark on the colour wheel See Ink Black Green on the colour wheel
All matches: Dryad Bark equivalents · Ink Black Green equivalents