Scotch thistle seeds, scientifically known as Cirsium vulgare, originate in Europe and Asia. They have spread widely across the globe, becoming invasive in some regions. These seeds possess a spiky exterior, protecting them from birds and animals. Once dispersed, they can germinate in various soil types, establishing new thistle populations. Their bitter taste and spiny leaves deter grazing by most animals, except for the larvae of some butterfly species that feed exclusively on thistles.