Identifying Yarrow (Achillea millefolium)

Take great care when identifying wild plants and fungi, this blog is not a resource to be taken by itself and further resources will be linked. Consult other sources and double check. While foraging is an extremely rewarding and useful skill, numerous common plants and fungi can make you sick or kill you. Be absolutely sure of what you’re eating and, when gathering, ensure you leave enough not only to ensure the survival and growth of the species but also enough for others to enjoy, from the human and more-than-human communities. Also cultivate an awareness of contamination and pollution – wastewater runoff, spraying, exhaust fumes – as this should affect your decision to harvest.

The Plant

Achillea millefolium is a flowering herbaceous perennial plant from the Asteraceae family. They are native to Asia, Europe, and North America in temperate climates and have been cultivated in Aotearoa as animal feed. The name Achillea comes from the Greek hero Achilles who purportedly used the medicinal herbs in this genus to heal his soldiers in the Trojan war. Millefolium means “many leaved”, derived from the Latin words “mille” (many) and “folium” (leaves). The common name yarrow is thought to have come from the same root word for “yellow” in Old High German.

Description

Yarrow is a perennial flower that grows easily and prolifically as a “weed” in New Zealand gardens, riverbanks, roadsides, and farmlands. They begin as a fluffy basal rosette of feathery leaves with each long and narrow leaf growing up to 6 inches long and 1 inch wide (largest at the ground, becoming smaller up the stem). Some leaves will sprawl along the ground while others may be more erect and they are fernlike and strongly divided along the leaf stalk. Each plant will produce one to several stems which are covered in fine hairs and stand erect 8-40 inches in height. The white to pinkish flower clusters are flat and grow at the end of each stem. Each flower is tiny with six rounded petals and the centre of the flower is round and has many holes which you can often see containing yellow pollen. They have a very sweet scent. Yarrow is a dioecious plant and is pollinated by bees, butterflies, flies, and beetles. Yarrow self seeds easily and can also reproduce asexually via extensive networks of underground rhizomes.

Ecology

I have come across Achillea millefolium growing wild all around Aotearoa especially in the countryside. Many people will also intentionally plant yarrow or their various colourful cultivars in herb or decorative gardens. The greenery of yarrow can be found all year round while the flower heads are blooming most of the year from spring through to autumn.

Nutritional & Medicinal Information

Yarrow’s astringent and antiseptic properties makes it a wonderful herb for reducing bleeding and also healing wounds. A poultice of bruised yarrow leaves can be used to treat rashes, eczema, and insect bites topically.

The Pawnee and Chippewa Nations use yarrow poultices for headaches and other aches and pains and the Cherokee people often use yarrow tea for flu symptoms such as sore throats, coughs, and sinus issues.

Historically bitter yarrow tea has been taken for stomach upsets and to support digestion and taken to ensure a restful nights sleep. Drinking a hot tea of yarrow leaves or powder and wrapping up in a blanket can help with sweating and breaking a fever. Cups of strongly brewed cold tea can help flush out urinary tract infections.

Yarrow tonic can be taken to help soothe menstrual cramping and reduce bleeding, as well as calming the nervous system which eases anxiety and stress.

The dried yarrow leaves can be smoked to help with catarrh by helping to expel mucus blocked in the sinuses or throat.

Large doses of this plant can cause adverse reactions in some people topically or internally and so should not be consumed in large amounts. People who are pregnant should also avoid consuming yarrow as they can have a stimulating effect on the uterus which can result in miscarriages.

Possible Lookalikes

Poison hemlock (Conium maculatum) could be mistaken for yarrow and is incredibly poisonous. One way to tell the difference is that yarrow has slightly hairy green stems while poison hemlock has smooth stems, generally with purple blotches/spots/discolouration. Poison hemock grows much taller than yarrow and while it has small white flowers they grow in larger umbel shapes, not flat. Yarrow has a floral fragrant scent while poison hemlock smells disgusting. If you cannot correctly identify yarrow then it is best to avoid this plant.

Wild Carrot (Daucus carota) looks similar to yarrow and thankfully wild carrot roots, leaves, and flowers are edible. Wild carrot leaves are much less feathery than yarrows and their round flower umbels are much bigger with a small dark purple flower in the centre.

Interesting Facts

Due to yarrows dense rhizomes and roots they are a great plant to sow to reduce soil erosion.

Some Native Americans used ground yarrow leaf infused water as a soothing wash to treat sunburn.

Yellow and green dyes can be obtained from the flowers.

Yarrow soaked in water makes a great fertiliser as they contain nitrogen, phosphorus, potassium, and copper. This tea can also be added to a compost pile to help with decomposition.

Storage & Cooking

Gather yarrow leaves and flowers in summer when the flowers are fully open and blooming. You can use the fresh or dried leaves and flowers brewed in hot water to make a fragrant tea. This tea has also historically been used in wild beer brewing and the flowers have been used to flavour alcohol.

Dry the leaves and flowers by hanging the stems in a dry place away from direct sunlight or heat. You can then grind the leaves into a powder to use for teas or as a flavouring in cooking.

Yarrow leaves are fairly bitter and you shouldn’t use much when cooking as they can be over powering. Fresh leaf tips are delicious in salads, pastas, and stews.

Enjoy my fellow foragers!

Further Reading

New Zealand Plant Conservation Network

Philadelphia Orchard Project