Our visit to Alverstone Mead this week saw us pulling the dreaded ragwort yet again (we must be world experts at this by now). We worked in several fields where cattle regularly graze, and there was an excellent turnout despite the poor weather forecast. We did experience a few drops of rain but our main difficulty was extremely strong winds, which threatened to take us off our feet at times.
The ragwort on the Mead is not the same as that on Brading Down but is known as Marsh Ragwort (Senecio Aquaticus), and often has a rather unkempt appearance. It is shorter, more widely branched and less stiff than common ragwort, with glossier leaves mostly with a large end lobe and much smaller forward-pointing side-lobes, with oval root-leaves which are often undivided. The flowers are much less densely clustered than those of other members of the ragwort family, and the petals are relatively long compared to common ragwort. It is found mainly in marshes, ditches and on damp shaded riverbanks, flowering in July and August.
Ragwort contains alkaloids that are toxic to cattle, deer, pigs, horses, and goats. Sheep appear to be less affected, and can consume great quantities without apparent injury. In susceptible animals, the alkaloids cause degradation of liver function, with lethal results in one to two days when the animal ingests three to seven percent of its body weight in Ragwort. However, such acute poisonings seldom occur because the low palatability of the plant usually results in only small quantities being consumed per day. Chronic effects result from a gradual loss of liver function that eventually develops into a cirrhosis-like condition, eventually leading to death.
This week the photographs were from Eddie & Carrie and Carrie wrote the text (inluding the "nature lesson"!) Many thanks.
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