A NATIONAL trade body has warned residents about an "extremely toxic" weed growing across the city that has injured adults and children. Over the years a number of children, as well as adults, have reported injuries after coming into contact with Giant Hogweed in the UK. Hogweed is not only dangerous to humans but to dogs well - coming into contact with the plant can cause redness and itching to a dog’s fur. In some cases, it can cause scarring to the eyes and even blindness. The invasive weed is capable of growing to a height of up to five metres and can produce up to 30,000 to 50,000 seeds, which can survive in the soil for a number of years.