Wild lettuce hails from Central and Southern Europe, but has naturalized across much of the globe. Wild lettuce is typically categorized as a weed for several reasons. Firstly, it has a high capability to reproduce and spread rapidly, mainly due to its highly prolific seed production. Secondly, it's a stout and hearty plant, capable of thriving in a variety of environments and it shows significant tolerance to weather fluctuation. This robustness often allows it to out-compete other, more desirable, plants in a garden setting. The plant's aggressive nature can pose a threat to biodiversity, as it may push out other species, alter habitats and reduce overall ecological balance. Wild lettuce primarily spreads by seeds, which are released in large numbers and can be carried by wind or other means, allowing it to invade new areas. The seeds may also be transported on clothing or equipment, or in soil or compost, quickly turning the plant from a minor nuisance into a major invader.