Dock

Curly dock is easiest to spot in late summer, when its tall seed stalks turn rusty red-brown and stand out across fields and ditches. They stay standing well into winter.

It's a tough perennial in the buckwheat family, with a deep taproot that lets it survive droughts, mowing and most attempts to get rid of it.

How to spot it

• Leaves are long and narrow, up to 30 cm, with very wavy, crinkled edges. That's the "curly" in the name.
• Stems are grooved and often reddish. A thin, papery sleeve wraps the stem where each leaf joins it.
• Flowers are small and green, in dense rings up tall, branching spikes.
• Seeds are wrapped in three papery, heart-shaped wings that turn from green to red-brown.
• The root is yellow inside, which is where the name "yellow dock" comes from.

What it's good for

Young spring leaves have a sharp, lemony taste. They're good cooked, but they're high in oxalic acid, so don't eat them in large amounts. The seeds can be ground into a dark flour if you have the patience.

Herbalists use the root as a bitter tonic and a gentle laxative. Many people grew up rubbing dock leaves on nettle stings, and it's still a handy trick on a walk.

The root also makes a yellow dye.

Don't confuse it with

Broad-leaved dock has wider leaves with a heart-shaped base and flatter edges. You can use it the same way.