If you have freezer space, freezing is often the simplest
preservation method available, requiring no special technique
beyond reasonable portioning and packaging.

Most berries from section 5.2 freeze well raw. Spread them in
a single layer on a tray first to freeze individually, then
transfer to a bag or container — this keeps them from clumping
into one solid mass, making it easier to take out just what you need later.

As covered in section 6.3, most mushrooms freeze better after
cooking rather than raw. Sauté until the released water has
evaporated, then cool completely before freezing in portions —
raw mushrooms tend to turn watery and limp once thawed.

Nettle, ground elder, and other leafy greens from section 5.1
generally freeze better after a brief blanch — a quick dip in
boiling water, then immediately into cold water to stop the
cooking. This preserves colour and texture better than freezing raw.

Freeze in portions you'll actually use at once, rather than
one large block you'll need to thaw entirely each time.
Label everything with contents and date — frozen food is
easy to forget about, and even well-frozen foraged food
is best used within a reasonable time.