If you are in zone 6B, I would get with the program. I'm in 8A and I plan to spread my CGM next week. Next time you need to purchase CGM, go to a feed store and buy the generic brand. It's absolutly the same stuff and you should save $5 a bag or more. I buy 50# bags for $17.

Fall pre-em should be applied when the soil temperature reaches 70F. In Northern Illinois, the soil temperature is currently about 72F. I'm guessing that soil temperature in Tulsa would be warmer.

-Deerslayer

Do you guys know of other feed store in that sells CGM IL other than Elburn Co-op, Blackberry Station?

Where can I find out what my local soil temps are? It is starting to cool down here but its still in the 80s.

One way is to buy a soil thermometer. Here's an example.

Soil Thermometer

In Illinois, the Illinois State Water Survey publishes the data.

Illinois Soil Temps

Perhaps a similar site is available for Oklahoma.

-Deerslayer

I did a quick Google search. Try this site.

OK Soil Temps

Select the Soil Temperature Under Sod (10 cm), then click on the state map.

-Deerslayer

I just noticed that the maps at the above site haven't been updated since June 1999. Anyway, you get the idea. Your homework is to find an OK Soil Temperature Site. 8^) If one isn't available, consider purchasing a soil temperature thermometer.

-Deerslayer

This must be a record. Four posts in a row!

I found it!

OK Soil Temp 10cm Sod

Click on "Soil Temp 10cm under Sod" at the bottom of the left hand column.

-Deerslayer

Thanks Deerslayer, looks like yesterday it was 79* but today were down to 74*. Guess I'll be putting it down this weekend and see if it'll help out with the weeds.

Deerslayer, where did your info about soil temps and the application of CGM come from? I have never heard this before. In my zone 8A, the weeds would be sprouting before my soil got to 70 degrees. In my sitution, we make application based on time frame rather than soil temps. As I have stated many times, CGM works as a preemergent only on annual weeds. It works as a great fertilizer on prennial weeds.

"where did your info about soil temps and the application of CGM come from?"

From the University of California. Here's a link.

Pre-em Soil Temp

It's just above the first table. The 70F recommendation is specifically for Poa Annua, however, most annual grassy weeds that germinate in the fall germinate near that temperature.

If you are trying to control annual broadleaf weeds with CGM, 70F may not apply. You may want to check the germination temperatures of the specific weeds that you are trying to control.

BTW, the September 11 soil temperature was 70F here in Saint Charles, IL. I've seen September 15 recommended as the date to apply fall pre-em. Is that the date when you apply?

-Deerslayer

TexasRedhead, I don't know where you are located in Texas but the 8:30 am soil temperature is at or near 70F in many West Texas towns today. Here's a link.

Texas Soil Temps

-Deerslayer

To begin, you are 600 miles north of me in the Ft. Worth area. Much of west Texas is high plains, that is 4-5,000 ft. higher than us. Amarillo and Lubbock have cold winters and snow. Another key we have here is the growing patterns of St. Augustine grass. It requires warm soil and warm/hot nights to trive. I am still mowing mine every 4 days. We won't see a real slow down till late Oct., early November. We are still having days well into the 90ties. I will be applying CGM this weedend or next.

I live in North East Illinois. Like I said, I initially didn't know where in Texas you were located. I realize that Texas is a big state with many different growing conditions. I happened to easily find West Texas soil temperatures, that's why I posted them.

Which weed seeds germinate when air temperatures are in the 90s? What's your current soil temperature?

-Deerslayer