Preemergence residual herbicides

[gil.gullickson]

All,

How many of you are using preemergence residual herbicides on your soybeans this year? I have a gut feeling more is being used in years past due to comments at meetings I attend, but just curious if that gut feeling is right. It's a great way to get a headstart on weeds, but it does add cost, too.

Thanks,

Gil Gullickson

Crops Technology Editor

[Blacksandfarmer]

Used a pre in beans a couple years now. Stunted beans both years. Used a disc pre this year. Ive seen more tillage this year than I have in a while. Maybe thats just a "here" thing.

[Jim Meade / Iowa City]

I'm using Valor as a preemergence and Outlook as a post with a little residual.  My early soybean weed control has been good the last few years, but I get late season weed flushes and hope the Outlook will extend the effective period.

[buckfarmer]

This is my second year of using sonic. It worked very well last year, totally eliminateed marestail. It seems kind of expensive though.

[buckfarmer]

Blacksand, what were you using that burned your beans. AND if you listen to some "experts", stressing beams early like that helps yeild.

[Blacksandfarmer]

Buck, I had the local elevator spray Envive by Dupont preplant. My beans shot out of the ground nice, but after a cool wet spell they never were the same. I have heard any herbicide that contains Valor can be hard on beans if the chemical splashes onto the beans. Also we have low CEC soils. I would imagine if I had told the elevator to only spray a half rate I would have been better off.

[Shaggy98]

I've never been a 1/2 rate fan.  How do you control the other 50% of your escapes?

[Jim Meade / Iowa City]

Valor is a preemerge herbicide.  I wouldn't want any beans poking through when it's applied.  Also, I limit mine to 3 oz/acre although one can go to 5 because of carry-over issues.

[gil.gullickson]

All,

Thx for your input. You know, I remember last year there were some injury problems early on, I think, with preemergence herbicides, so I'll look into that. 

Thanks again,

GIl 

[Blacksandfarmer]

Shaggy, I have some ground with less than 2% organic matter. Some residual herbicides can be tough of beans when organic matter levels are that low.