Scleranthus (Scleranthus annuus)
Scleranthus, the remedy for those who are indecisive, is made by the sun method.
It is part of the carnation or Caryophyllaceae family and is known by the common names German knotweed, German knotgrass or (annual) knawel – the latter name coming from the 16th century German Knauel for knotweed (literally, ball of yarn).
Native to Europe, Asia and North Africa, it is sometimes considered to be a weed. It is low-growing, forming dense mats and has inconspicuous green flowers. In the UK, intensive arable farming with increased use of broad-spectrum herbicides has led to its decline and it is regarded as endangered in the wild. Knawel has been used as a cure for toothache and the sweet-tasting leaves are fairly good fodder for sheep.
Perennial knawel (Scleranthus perennis) was used as the host plant for the Polish cochineal bugs (Porphyrophora polonica). Polish cochineal dyes were developed by the ancient Slavs and provided an economically important trade in Europe until the 16th century when the cheaper (Mexican) cochineal we know today (from Dactylopius coccus – hosted by prickly pears (Opuntia spp.)) was introduced. The dye was used to colour textiles and, in Poland, as a colourant for some vodkas.
The female bugs lay eggs in the ground and the larvae feed on the low-growing host plants, initially on the leaves but then on the roots, forming protective cysts. Female larvae are harvested before they reach maturity – the plant is uprooted and yields approximately 10 insects. Harvest occurs in late June, around the time of St. John the Baptist’s Day (June 24th) and the resulting dye was sometimes known as Saint John’s blood. The larvae were killed using vinegar or boiling water and dried. The resulting red dye arises from a chemical compound produced by the larvae for protection called carminic acid. This makes up approximately 0.6 % of the dried insect’s body weight. This is much less than the quantity produced by the Mexican bugs (approx. 20 %).
The process was not only labour-intensive but, as the plants were dug up to obtain the insects, they had to be replaced after each harvest and knotweed was grown in plantations. Along with the much reduced yield of carminic acid from Polish cochineal larvae, this accounts for the relative expense of Polish cochineal dye. In the 18th century, Polish cochineal began to be exported again, to Russia and Central Asia but today, the use of the dye is rare and in some places e.g. the Ukraine the insect is considered endangered.
The legacy of the use of Polish cochineal can be seen in Slavic languages, where the words for red and June (or July) come from the word for worm. In Polish for example, the three words are czerwony, czerwiec and czerw, respectively.
Scleranthus biflorus is native to Australia and New Zealand, where it is known as cushion bush or lime lava. It resembles moss and is sometimes termed “Australian astroturf” and grown to give green ground cover in dry conditions. An ointment made by drying the plant and mixing the powder into a paste with New Zealand passion flower (Passiflora tetrandra) was sometimes used to ease itching by the Maoris.