St Johns Wort is flowering here at the moment- there are hillsides covered in flowers. There was a time when the local Weeds Officer would issue a notice to take steps to eradicate it or pay a fine. When merino (or any other white faced breed) sheep eat a lot of it, it makes them photo sensitive, prone to sunburn and also greatly reduces their pain tolerance. They get scabs and sores on their faces, particularly around eyes nose and mouth, and in really bad cases the skin on their entire muzzle will become like a thick, hard pie crust and will crack open and bleed if they bump it, causing them a lot of pain. Bees like it.
The governemnt here announced- probably forty years ago now- that they intended to release an insect to control the wort. It was a shiny little black beetle. The beetles turned up on our place a year before they supposedly were released. There would be heaps of them on every stem and as you approached they would see you and drop to the ground- in a big area of thick wort with countless millions of beetles, it sounded like rain just ahead of you as you walked.
I listeded to an interview once with two Australians who intended to start a business extracting whatever it is they extract from the wort. They found a property with heaps of the stuff in full flower, gained permission to take as much as they wanted, and spent the day gleefully harvesting wort flowers by hand. As they drove home that evening with their load, tired but satisfied, they looked at each and both burst into tears. Eventually they realised that if you want to pick lots of wort by hand, you really do need to wear gloves- it's absorbed through the skin after all
