Guildford Grass is a rather nasty weed which if left untreated will spread very quickly to take over a lawn in only a few seasons. Guildford grass has a long thin stem which is dark green in colour and very tough. At it's base is an underground brown corm (bulb), and as the weed matures it will produce some rather beautiful pink or white flowers.
Despite the pretty flowers, this weedy member of the Iris family is a major curse of lawn owners everywhere. When mowed, the tough green stem will slash instead of cut, often leaving the stems sitting higher than the rest of the lawn, and after a day or two, the slashed stems will brown off at it's wounds - leaving for a very ugly look to our lawns.
The very best time to control Guildford Grass is when it first becomes apparent in the lawn. It will always establish in only a few places to begin with. When first seen, each weed should be physically removed from the lawn which is best done with a knife or similar small garden tool.
Removing the grassy stem alone will do nothing, the corm (bulb) must be removed below the soil surface.
Another method is to use some Glyphosate (Roundup type) herbicide mixed up in a small container. the weed killer is then painted onto the individual stems of all the weeds.
WARNING: Glyphosate is a non-selective weed killer. It will kill any plant it comes into contact with - including lawns - so caution should always be exercised.
The greatest problem with Guildford Grass has been it's resistance to all weed sprays, but this has now changed - there is now a selective weed killer available for use on lawns which will kill Guildford Grass.
However, this herbicide is controlled and is not available to the general public. For severe infestations of Guildford Grass, the homeowner should contract a Professional and Licensed Weed Sprayer to get the wee controlled quickly and effectively.