High pH is defined here as 7.4 - 8.1.  and Low O.M. soils is 1.2% - 1.5%.

We have significant areas of the field that the pH's and O.M levels are within the range defined above and are finding it hard to find a pre-emergence that doesn't cause crop injury or carryover to the following crop.  We have never had carryover problems going to field corn but have seen problems following with popcorn.  

We like to start clean with a field cultivator, plant then follow the planter with the sprayer to create that blanket of protection.  We use to incorporate a lot of chemicals with the field cultivator but since TWH we prefer to run the sprayer behind the planter.  I know laying these pre's down 15 days before planting helps with the crop sensitivity but the field cultivator just breaks that layer up prior to planting.  Been using 1.5 pt of generic Dual with 3 oz Authority First. Then followed by Roundup, (Cobra if needed) and some Warrent.  This program has worked well for weed control and I am not disappointed in that respect.  Liberty was my answer with a lighter rate of the pre's but everyone else was not on board.

I was wondering if cutting the Authority First back to 1.5 oz and adding some sencor at 2.5 to 3 oz, but sencor is sensitive on high pH soils also.  I'm really at a loss here.  Would Zidua and 1.5 oz Authority First work here better than the Dual?

Does anyone else have this similar problem and what have you used with good success?

 Edited for photo description:  This photo shows the carryover in the popcorn the following year.   

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