Glyphosate - Application Rate and Ground Speed

[Land_Owner]

Saturday I put herbicide in my two largest fields, alongside the adjoining roadways, and in multiple patches I use for wildlife plots.  I left the sprayer in a wetting "fine mist mode" while slowly driving my 4WD PU truck around in narrowing circles.  I have a Johnson grass infestation that multiple herbicidings has not eradicated. 

It is not known, and is asked, whether a fine mist is sufficient coverage or whether I wasted my time.  I will know for sure in 7-10 days and will report the findings but wanted some insight from those that may have tried similar applications.

The down side of the day was the overheating of the truck's transmission on the way home.  She belched an awful cloud of thick, white, acrid smelling smoke and then threw up all of her transmission fluid on the roadside.  Had to have her towed to the shop for a warranty repair.  The shop called yesterday to say the front transmission seal had "blown out".  No charge to me but they are checking all of the soft goods, replacing the seal and fluids, and will have her for four days tops.

[montveil]

when appling any pesticide  must calibrate you ground speed. best speeds are between 3-5 mph.
roundup can be applied in from 10-40 gallons per acre. roundup is a translocated hrebicide and does not need a fine MIST but droppl;ets about the size of a small pin head


at 1 mph a 11003 nozzle will 0.1 gallons per acre, at 40 psi hence if you are driving at 3 mph you will have to collect 0.3 gallons per miniute

                                                  i suggest you contact your local county ag agent on tha various calibration methods

[Land_Owner]

To be perfectly clear I was using a herbicide, not a pesticide, and Yes, I intellectually understand your response.  Performing the practical side of that understanding is something else altogether.  Calibration is not something that I performed and can only be guessed or tested at this time. 

I will have to do some research on the nozzle make/model.  I might need to perform a "beaker test" to gage the flow from the nozzle per minute (flow the nozzle for 5 to 10 minutes, capture the liquid, divide the volume by the time, etc.).  I can estimate or test the idle speed of my PU truck through waist high Johnson grass when it is returned from the repair shop.  Heck of a test for the reconditioned transmission right out of the shop.  Oh boy!

Or, let it stand that all of the 25 gallons of 0.50% concentrate solution was evenly applied to 1.25 acres (GIS confirmed area).  I hope to get a reasonable kill of the vegetation. 

From the above, was I too "hot", too "cold" or "just right"?  I am not a farmer and have much to learn...

[flintlock]

Landowner...I prepared one of my plots a few years back and I also had a Johnson grass problem...My local Southern States dealer told me that I needed to spray Johnson grass at least 3 times to kill it...This is what I did...First I mixed 2 oz per gallon of Roundup (50% concentrate)...I used a Honda Rancher with a 25 gallon sprayer, I pulled it in 1st gear and medium throttle it took about 25 gallons to spray the 1 acre plot.

I sprayed in mid-April, early July and mid-August...each time it killed the grass that was emerging...It did a good job and I planted my plot (wheat and clover) in mid-September, this took care of the problem and I still have a great stand of clover 3 years later....Now I control with monthly cuttings during the spring and summer months....Good Luck

[Land_Owner]

flintlock, I thought I had done that last Fall when I prepared the field in the first place.  I Glyphosated the Johnson grass (JG) to death, bush hogged and disced the field at brown-up, awaited JG regrowth, applied Gly again, waited again, applied Gly for the third time and STILL got a healthy stand of Johnson grass in the sorghum and peas that eventually were planted throughout the field.  I couldn't Gly the JG with the peas and sorghum so the JG seeded everything all over again.  So today, I am starting from scratch.

I have thought seriously about sterilizing the soil instead of using contact herbicide.  That is a severe step I am not really ready to take as I would like Summer and Winter plots.  Sterilization means not planting in that field for 2-4 months (depending on what I might use).  Residuals remaining in the soil could affect whatever I intend to plant in the future.  Neither prospect of sterilization is appealing.

[The Sodbuster]

You may wish to consider Outrider herbicide for Johnson grass.  Apply at about 1.33 oz/acre (read label, of course).  Cost is around $10 per ounce or a bit more around here.  Comes in granular form in 20 oz containers and it is he** on Johnson grass.  It's not a broad spectrum herbicide, like glyphosate.  But it's not strictly a grass killer either.  There are a number of broadleaves it will kill.  The label has a partial list.

[deerslayer79]

started using outrider 2 years ago and sodbuster is right,it is some good stuff,use it for yellow nutsedge control and works 10 times better than manage or sedgehammer..