If you have an invasion of Winter Grass, you’ll definitely want to treat it before it germinates. If you allow Winter Grass to drop its seeds, next winter it will be back, twice as badly as it was the previous year. Best plan of attack is to treat it as soon as it appears. It can be removed very easily by hand as it doesn’t have particularly deep roots and it doesn’t have any runners, growing in simple clumps. But if you’d prefer to spray, you’ll need to use Winter Grass Killer as a general purpose herbicide wont be effective. Amgrow Winter Grass Killer is safe to use on buffalo lawns (including Sir Walter DNA Certified), blue & common couches, but should be avoided on Kikuyu Lawns