Question
Jim--

The sod we put in (I believe it was a bluegrass mix) four years ago has a number of areas (each about 2'x 2')overrun with crabgrass.  There doesn't seem to be any weed-and-feed type product on the market (in California) that kills crabgrass after it has emerged, so I guess my option is to dig around the crabgrass patches to separate them from the good lawn, Roundup the crabgrass and remove them.

My question is: What do I need to do at that point to prepare the areas to be resodded so that they take well and blend in with the lawn?

Thanks for the help.

Mike

Answer
Hi Mike,

About Patching Sod Areas:

Where weeds such as CRABGRASS are dense and form patches in lawns, you can use a broad-spectrum herbicide like Monsanto's ROUND-UP (with glyphosate) for a fast and efficient sure eradication. This will usually work great and leave a dead place which you will have to re-seed or sod with turf grass. This herbicide and several variations of it are widely available everywhere.  Other chemicals such as MSDA and DSMA that target 'grassy-type' weeds can also be used.

Patching will turn out best if you can first match the old sod grass-type with the new. If you can't remember your sod's variety or patented name, the patch works may end-up showing a mixture of textures and shades of green.

Try to get the patch areas back to bare earth.  Work the top-soil to make it more friable and receptive to the new sod. Sod squares can be laid directly over the prepared soil areas and should be kept well-watered for however long it takes for them to bind to the soil. Once the sod has passed the 'Tug-Test', and cannot be easily up-lifted by hand; then it is well established.
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Incidentally, Bluegrasses (Poa species) due best where temperatures are not expected to hover near or above 85 degrees F (30'C).  In warmer locales these and all 'cool-climate' grass-types will be stressed and will demonstrate appearance problems.  When this happens, it is likely that their will be failed areas and places which will be taken over by weeds such as Crabgrass.
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Only Use plants and grasses rated for your climate-zone.
HORT ZONES from ZIP CODES:
http://www.arborday.org/trees/whatzone.html

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I Hope this has answered your question(s)!
Have a fantastic Summer!

Visit my Lawn & Gardens webpage for more Tips, Facts and Links:
http://hometown.aol.com/eilatlog/lawnol.html

Your Questions and Comments are welcome at ALLEXPERTS.com
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