Herbicide question relative to corn and grain sorghum

[whitewing]

My usual grain planting here in Venezuela involves only grain sorghum. This year I'll be planting about 120 acres of grain sorghum but will also plant about 35 acres of white corn. I know very little about corn production.

The recommended herbicide products (which are now really hard to find here) for corn are atrazine-based. One is a granular product, the other a liquid. The locals tell me to plant my corn via drill (I'll make two passes with the plow beforehand) and then spray immediately with these products before the corn emerges.

I've got a few questions maybe some of you can answer.

1) Can I spray before plowing and get the same week control results?
2) Can I spray after plowing but before planting?
3) Is there a risk to my seeded corn by following procedures 1 or 2?
4) When sraying these products, is there a risk to nearby emerging grain sorghum?

Thanks in advance for any help you guys can provide.

 

[sim.-ang.king]

I believe atrazine is a contact herbicide. So it really needs to be put on after planting so it can sit on the surface, and kill broad leafs as they emerge.
No it won't hurt sorghum.

 

[millstreaminn]

I always spray atrazine and Prowl immediately after planting. Atrazine keeps the grasses down, Prowl will keep broadleafs down. Occasionally spot spray with Roundup for any weeds the first 2 miss. (Obviously you need Roundup ready corn).

 

[tdc_cattle]

We use atrizine pre plant after our last tillage pass at about a half rate then again when corn is about a foot tall.