Ina, I DO use Roundup for spot treatments of certain invasive plants, including woody plants, and it is very effective. It is a good herbicide. But, it is evident we are not getting the whole picture. You can see it in this thread: several people have made most interesting comments about effects unknown or officially undescribed. Good for spot treatments of kikuyu but be very careful with using it in your vegetable plot as it is known that the product is absorbed by crops and remain in them.