I noticed a welcome sight, it was a cinnabar moth. Originally from Europe and Asia, this little moth was imported to help contain a noxious week. The cute little cinnabar loves to eat the developing buds on tansy ragwort thus keeping the weed from multiplying.
The cinnabar was brought in several decades ago and are no longer being imported. The critters that we are now seeing are the latest generation that has reproduced since that time. For many years we had seen a decline in the amount of cinnabar moths around here, but it seems that they are making a comeback.
Noxious weed control programs are in place to monitor tansy such as kingcounty.gov, their website states,
…tansy ragwort is one of the most common causes of poisoning in cattle and horses, caused by consumption of the weed found in pasture, hay or silage. Milk produced by affected cows and goats can contain toxins. Stock does not reject or avoid it in hay or silage; its poisonous alkaloids are unaffected by drying. Honey from tansy ragwort also contains the alkaloids.
Tansy is spread easily by the river that runs through the farm. High water brings in seeds and distributes them along the river bank. Seeds spread by the wind or by birds can have plants pop up anywhere around the farm.
As the weed is growing, the cows don’t disturb the area around it. Their natural instinct to avoid the dangerous plant works well. If the plant is dried and mixed in with the grass hay, they accidentally ingest the poisonous tansy.
We are always on the lookout for tansy ragwort and dig the plant out of the ground to get all the roots so it does not grow back. During hay season, all equipment is stopped if a tansy is spotted, removed from the hayfield, and close inspection of the area is complete. Many times tansy will grow in clumps of plants or several plants in a small area.