Round-up question.

[LD1]

I got 1-1/2 acres that I plowed and disc'd last year and planted soy beans. This is for wildlife (food plot).

Beans were Roundup ready, and sprayed last year.

This year, I didn't get around to spraying, but plowed and disc'd and planted Monday. Planted open pollinated (non-roundup ready) corn this year.

I know I should have sprayed earlier in the year, but that's neither here nor there.

So the question, if the corn isn't sprouted yet, which I don't think it is, wouldn't be wise to spray Roundup and 24d now, or is it too late assuming corn will sprout in the next few days?

 

[turnkey4099]

Unless there are weeds already growing tghere is no point in spraying either 24d or roundup. They are only effective in growing plants...at least roundup isn't, no too sure about 24d. I don't think either is a pre-emergent.

 

[LD1]

Unless there are weeds already growing tghere is no point in spraying either 24d or roundup. They are only effective in growing plants...at least roundup isn't, no too sure about 24d. I don't think either is a pre-emergent.

I plowed everything, but even so....plowing doesnt flip the furrow all the way over. Then I disc'd and planted in the same day. So yea, there is still some green stuff showing....that will no doubt re-establish after the 1.8" of rain we got the night I plowed and planted.

 

[LD1]

I know roundup and 24d are NOT pre-emergents.

The main concern is spraying herbicide.....days....(maybe hours) before corn sprouts up through the soil

 

[Oldoak]

Spaying with roundup now may cause injury if the corn is close to sprouting. The label suggests waiting 7 days before planting after applying roundup. From that, I take it you may do more harm the good to your corn planting. And I say "may" because I really don't know.

You do pose and interesting situation though. It would be interesting to know the outcome if you go ahead and do spray.

 

[CADplans]

2-4D is pre-emergent,,, it will inhibit ANY seed in the ground.
It is not normally used for that,, but, it will deter seed growth.

That is why you can not put down grass seed for quite a while after using 2-4D,,,

 

[smstonypoint]

I don't know the answer, but I would read the glyphosate and 2,4-D labels for guidance in making a decision.

Spot spraying and a wiper application would be alternatives.

Steve

 

[Silvic]

If there is no corn vegetation growth present as the herbicide hits the surface there should be no impact with Glyphosate. If there is even the smallest sprout you will kill it. If the weed has not yet broken the ground it will not be effected either; but any green growth that is there will be controlled. Glyphosate is not described as soil active and is adsorbed by soil very well. (half-life in the soil is between 2 and 197 days) It is thus bound to the soil until the bacteria slowly breaks it down. You may have germination at inconsistent rates in different spots on the field but if planted on Monday, 5 days ago, your chance of germination in 5 days is low.
As an additional issue if your soil is very sandy then the adsorption is much less than with highly nutrient rich soils thus the risk is higher since the adsorption is not as great. Note I use the term adsorb/adsorption which is a different process than absorb. (ad vs ab)
If you have germination below the surface (not yet visible) and the glyphosate soaks down and impacts the new growth before it binds with the soil you will have a problem.

I would not suggest doing as you describe as the risk is too high depending upon your soil. I believe the label (I do not have it available at the moment) states an interval after use before planting.

2,4-D I would not recommend from your description. I don't know if you are thinking of the using the salts, esters, or the acid form of 2,4-D so can't give specifics however the half-life in the soil varies from 1-14 days unless you are using the ester version which has a half-life in aquatic sediment of 186 days. It does not adsorb as well to soil and can remain unbound much longer depending upon which version you are using. Too high a risk from what you describe.

In any case it is a federal law requirement and most state laws as well to read and comply with the label. Way too many folks don't do that. In my state it is $7500 fine for a violation of the label.

 

[LD1]

Interesting about 24d??

24d is a broadleaf herbicide. You are saying it will adversly effect corn seed?

This is from the buccaneer brand (glyphosate) label

USE INSTRUCTIONS: This product may be applied alone or in a tankmixture
betore, during or after planting corn. Applications must be
made prior to emergence of the crop.

Leads me to believe that if I dont have any sprouts yet....and dont drench the ground, I will be ok.

And no I dont drench the ground, When I spray, its 15 gallon per acre. And a quart per acre.

 

[Fossil Farm]

Yes, 2,4D is for broadleaf plants. Does not affect grasses like corn. Since you planted Monday, you could dig up a few kernels and see if they have
geminated and/or how far along they are. For 1 1/2 acres mainly for a food plot, it would take longer, but I would probably just spot spray with
Roundup to avoid possible injury and spraying bare ground where it is just a waste of the chemical (and money). Roundup has to be taken in by
the plant leaf to be effective, but if it is going to poke out of the ground this weekend, with the warm weather we are having, I would hate to take
the chance of an overall spray. Good luck.