Roundup Mix(up)

[dalroo]

Novice question - I should've asked in advance. Bought a sprayer and did some herbicide over the weekend. I read the mixing instructions over several times, and was pretty confusing. I ended up with roughly 0.5 oz per 1 gallon of Roundup Pro Max on coastal and mixed weeds mostly less than 6 - 8" tall. Sprayed at roughly 25 gallons per acres. Now I'm thinking I was way light with the glyphosphate.

Any thoughts? Too little? Close to right? Did I just waste a bunch of chemical? How long for results - or lack of?

 

[Coyote machine]

Novice question - I should've asked in advance. Bought a sprayer and did some herbicide over the weekend. I read the mixing instructions over several times, and was pretty confusing. I ended up with roughly 0.5 oz per 1 gallon of Roundup Pro Max on coastal and mixed weeds mostly less than 6 - 8" tall. Sprayed at roughly 25 gallons per acres. Now I'm thinking I was way light with the glyphosphate.

Any thoughts? Too little? Close to right? Did I just waste a bunch of chemical? How long for results - or lack of?

Here is a link to various applications of the product. You could always reapply if you went too lightly 1st time out.
Application | Roundup PROMAX(R) Herbicide | Monsanto IT&O

 

[MAN IN BLACK]

You should see results in 7 to 10 days if your mixture was right.

 

[ultrarunner]

Sounds a little light and a little late...

I try to hit it when 6 to 9 inches...

 

[rustyshakelford]

I try to mix around 3-5 oz per gallon

Brett

 

[Silvic]

I had to look up the Roundup Plus Max which is produced by Monsanto (5.5 lbs A.I. per gallon) to see what their label states as I have never used it.
I use generic 61% active ingredient glyphosate which is 4 lbs A.I. per gallon.

Most folks use too high a concentration and end up burning the foliage too fast and thus never give the plant the time to translocate the chemical to the roots. Result is it appears that you kill the plant (it turns brown) but you did not and it will grow back from the roots as they are not dead.

Your 0.5 oz per gallon (page 3 note 4 from the Monsanto Roundup Plus Max label ) shows that you used a 0.4% solution. I like a 1% solution on most plants. Not familiar with your coastal and mixed weeds in south Texas but 1% will work on most tough weeds quite well. Since you used 0.4% it might take a bit longer to see the effects and the tougher weeds may not be completely killed just stunted. Easy weeds will be effectively killed with the solution you used.

Having said all that, your 0.4% solution is label authorized. The label is the law. Any use not in compliance with the label is a violation of federal law and most likely state as well. Always read the label and follow it. Don't want to sound like the EPA police but it is for your health, your family, pets and the wildlife in the area. I could go further but while Glyphosate is very safe it still needs to be used IAW the label.

 

[dalroo]

Thanks For the feedback! Sounds like I am light, but may still get results. Will update when I can report effectiveness.

 

[scdeerslayer]

You need to figure out how many gallons you spray per acre, from there, reading the label on whatever product you're using should tell you how much to apply per acre. This is probably the easiest way to calibrate your gallons per acre:Field Sprayer Calibrator | GEMPLER'S. You need to make sure you can constantly spray with the same ground speed and if using a PTO sprayer you need to always spray at the same RPM and with the same PSI in the sprayer lines.

 

[LD1]

With most herbicides and insecticides dilution rate doesn't matter as much as how much product you apply per acre.

IE, 12 oz mixed with 25 gallon of water applied over 1 acre (as you did) would have the same effect if you mixed 12 oz with 15 gal and sprayed 15 gal on that acre.

With 41% concentrate glyphosphate, the target is usually a quart per acre. With your slightly more potent 48% mix, that would equate to about 27-28 ounces per acre. You sprayed 12 per acre.

I thin you are light. I typically mix 3-4 ounces per gallon. It goes on plenty heavy with a hand sprayer. The 2-nozzle sprayer on the 4-wheeler will spray it's 15 gallons @ 3mph and cover right at 1 acre. So it gets 1 qt when I mix it. A little lighter than the hand sprayer cause that works out to 2oz per gallon.

The label is your best friend. Read and understand it. Too little and your wasting money because you have to do it over. Too much and your wasting money with no better results and sometimes worse results.

 

[RickB]

Half rates of herbicides make major contributions to the problem of herbicide resistance. Escapees breed and their tolerance to low rates morphs into tolerance to full labeled rates. Natural selection at work.

 

[Lineman North Florida]

With a hand sprayer I mix 4 ounces to the gallon and have always had a good kill, I also like to add a couple of ounces of sticker or mineral oil will do in a pinch.

 

[JimRB]

I used some generic glyphosate in a 3 gallon Solo backpack sprayer. I mixed 1% one day. 2 days later I did 2% on another section. 1% killed just fine. In a week all was just as dead with 1% or 2% as far as I can tell. I have not tried any experiments with less than 1% active ingredient. Now the question would be how much area did I cover. That would require me to measure as I was trying to clear a 12' wide path. And that leads back to the observation someone made of active ingredient per acre of square foot. I read the label for 2, 4D and the generic stuff I spray means 1 gallon in 50 gallons of water over about 5 acres seems to knock the weeds down nicely. I haven't sprayed that in bulk in a few years so I do not have the active ingredient per acre rate. 2,4D has something on the label that say no more than x per acre per year. I know, just repating what others have said.

 

[dalroo]

Updating for results - it has been 3 weeks since I sprayed and I checked the areas this weekend. The .4% killed all of the weeds and 75% of the grass. The grass that was still alive was stunted and yellowed and may die out, but not yet. Based on these results, and the comments here, in the future I will plan to increase the mixture to 1%, but keep the rate of spray the same. I think that will be about right for the area I am working.

For this year, if the weed/grass reappear before I plant, I will go ahead and spray again, but hoping that is not necessary.

Thanks for the comments.

 

[AGRIMAN]

Updating for results - it has been 3 weeks since I sprayed and I checked the areas this weekend. The .4% killed all of the weeds and 75% of the grass. The grass that was still alive was stunted and yellowed and may die out, but not yet. Based on these results, and the comments here, in the future I will plan to increase the mixture to 1%, but keep the rate of spray the same. I think that will be about right for the area I am working.

For this year, if the weed/grass reappear before I plant, I will go ahead and spray again, but hoping that is not necessary.

Thanks for the comments.

i dought you have killed the coastal. I suspect it will return.