Jacobaea vulgaris

Jacobaea vulgaris, also known as ragwort, is a common wild flower belonging to the Asteraceae family. It grows naturally in northern Eurasia, especially in dry and open areas, but it has spread to many other places as a weed.

This plant has many names, including common ragwort, stinking willie, tansy ragwort, benweed, St. James-wort, and others. In the western United States, it is usually called tansy ragwort or simply tansy, even though it looks only a little like the true tansy.

While Jacobaea vulgaris can be harmful to farm animals like cattle and horses because of its toxins, it also provides valuable nectar for insect pollinators. This makes it important for nature even in places where people consider it a nuisance.

Description

Jacobaea vulgaris is a tall wild flower that can grow between 0.3 to 2 metres high. Its leaves often have a strong, not-very-pleasant smell, which is why some people call it "stinking willie" or "Mare's Fart." The flowers are bright yellow and grow in dense clusters, blooming from June to November.

The plant is pollinated by many types of bees, flies, and moths and butterflies. Each plant can produce up to 2,500 flowers and as many as 120,000 seeds, which are easily carried away by the wind thanks to special prickly hairs on them.

Taxonomy

There are two types of this plant. The first type is the usual plant, and it has special flowers called ray florets. The second type does not have these ray florets.

Distribution

Ragwort grows naturally across Europe and parts of Asia. It can be found in many places such as Scandinavia and the Mediterranean area. In Great Britain and Ireland, it is common in fields and along roadsides.

This plant has also been seen in other parts of the world, including North America, South America, Africa, Asia, and Australia. It likes to grow in areas with poor soil, like waste land and roadsides.

Ecological importance

Ragwort, also known as common ragwort, is often seen as a unwanted plant by landowners because it can harm cattle and horses. However, it plays a very important role for many insects. It provides a lot of nectar, which helps pollinators like bees and butterflies.

In the United Kingdom, ragwort supports at least 77 different insect species. Thirty of these insects eat only ragwort, and another twenty-two rely on it as a major part of their diet. Many of these insects are rare, with ten species considered threatened or scarce. These include the cinnabar moth, a special species that depends entirely on ragwort for survival.

Poisonous effects

Ragwort contains many different plant chemicals that can harm animals. These chemicals are called alkaloids, and several have been identified in the plant.

People who keep horses and cattle need to be careful about ragwort. In places where ragwort grows naturally, such as Britain and parts of Europe, horses and cattle usually avoid eating it because it tastes bad. However, they might eat it if there isn’t enough other food available. If ragwort is dried and stored as hay or silage, animals can’t tell it’s there, and it can affect the whole batch. Eating enough of it can seriously harm a horse’s liver.

There isn’t a specific test to confirm ragwort poisoning, as the liver changes it causes can also happen from other harmful substances. While there is no cure, horses that stop eating ragwort can sometimes fully recover. Small amounts of the plant’s chemicals can be absorbed through the skin, but this is much less harmful than eating it. Some people might have skin reactions to ragwort because of other plant chemicals it contains. Honey made from ragwort has tiny amounts of these chemicals, but not enough to be harmful.

Control

Ragwort, also known as common ragwort, has become a problem in many places where it was introduced. People use different ways to stop it from spreading.

In places like Tasmania and New Zealand, ragwort costs a lot of money to control. In Ireland, laws require landowners to manage ragwort growth. In the United Kingdom, certain rules help control ragwort, but landowners aren't always required to remove it.

One natural way to control ragwort is by using insects that eat the plant. For example, the cinnabar moth's caterpillars eat ragwort and are not liked by other animals because of their bright colors. This moth has been used to help control ragwort in places like New Zealand and the western United States. Other insects, like the tansy ragwort flea beetle, are also used to fight this plant.

Other usage

In ancient Greece and Rome, people believed they could make a special mix from this plant to help with love. They called this mix satyrion.

You can use the leaves of the plant to make a green color for coloring fabrics, though the color may fade over time. The flowers can be used to make a yellow color if the fabric is treated with a special substance called alum. Some people also say the plant can be used to make brown and orange colors.

Literature, poetry and mythology

The Greek doctor Pedanius Dioscorides (around 40–90 CE) suggested using this plant for healing. Two famous plant experts, Gerard and Culpeper, also spoke well of it. Culpeper believed the plant had special powers because of the stars.

The poet John Clare liked the plant very much. In a poem from 1831, he wrote nicely about it. In the Isle of Man, this plant is called Cushag and is their national flower. A story says a king named King Orry chose it as a symbol because its petals stood for different islands. The poet Josephine Kermode also wrote a lovely poem about the Cushag.

There is also a fun story from the Isle of Arran about fairies using the ragwort flower to travel to Ireland quickly.