barn yard grass
how do I get rid of this from my lawn weed killers do nothing.a land scape co. Tried several applications and nothing worked
Otsego County Michigan lawns and turf
The good news is that Barnyardgrass is an annual and will die off end of season. The not so good news is that it readily reseeds. Means that the plant needs to be eradicated in some way before it flowers and goes to seed. Easier said than done as you have learned. Otherwise it just returns each year from seed. Pulling/digging making sure all root is removed is an option. This would have to be done early when the plant has emerged and before it quickly grows into a large clump.
Barnyard grass can also be controlled, at least partially, by applying a pre-emergent. A pre-emergent refers to the use of an herbicide that prevents weed seeds from emerging or kills very young seedlings early in the season without injuring turf grasses. The most common products are labeled crabgrass preventer. The crabgrass preventer will also prevent barnyard grass seeds from germinating. Length of prevention will vary depending on the type of chemical used. The pre-emergent can be purchased by its self or in combination with fertilizer. Do not use pre-emergent if you plan on seeding your lawn because these products will also prevent desirable grass seed from germinating. Know also that seeds can remain viable for several years, meaning that diligence would be required in succeeding years.
An organic product for helping control barnyard grass seeds from germinating is corn gluten meal. This will also prevent grass seed from germinating.
Go to this link for more on Barnyardgrass: http://extension.psu.edu/pests/weeds/weed-id/barnyardgrass The long term fix after eradication is creating a healthy stand of turf grass, with no room for foreigners to germinate.
I see nothing mentioned about non specific herbicides such as glyphosate. This may work but could kill everything else as as well.
We can't recommend specific products or businesses, but personally when I have a difficult weed/turf issue to resolve I look to Farm N Garden in Kalamazoo for solutions. http://www.farmngarden.com/
Good luck to you!