Pin oak

Watercolor pencil again, but better quality.  Creatacolor rather then Crayola.

Sycamore maple

Watercolor pencil, using cyan, magenta and yellow primaries, with dark blue for shadows.

Red oak

Tablet again

Beech

 Pencil

Narrow-leafed ash

Dip pens and walnut ink

Vine maple

 Walnut ink, using iris and foxglove stalks for pens.

Iris pen

 Experiments with pen and ink, using dried iris stalks as pens.