Southern rust was found yesterday just outside of Jackson, SC near Aiken. If growers in the Pee Dee haven’t applied a preventative fungicide yet, now would be a good time to start getting ready. We still haven’t seen rust in the area yet, so if your nerves will allow, give it another week or so before making that preventative application. It will probably take a week or two for it to move across the state. Keep scouting.
Strobilurin products are recommended for preventative treatments,though if rust is found in a field, a combination strobilurin/triazole will be better at slowing it down. If corn has been treated within the last 2-3 weeks, there’s a good chance it will need to be sprayed again. Our oldest corn is just starting to show it’s milk line, so we definitely aren’t in the clear yet. If we had just sprayed and were close to 50% milk line, then we would probably be ok for the remainder of the season.
Northern corn leaf blight is starting to pick up a little bit, so factor that into your spray decisions as well. Our corn crop is still looking really good. We got some rain this past weekend when we were really needing it. There’s not a whole lot of separation between irrigated and dryland corn right now.
The ears pictured above were collected from three different fields of varying ages managed by three different growers. The biggest difference is the irrigated ear has 18 rows of kernels and each of the dryland ears have 16 rows. Judging from the picture, we got good pollination this year.
For more information on corn production, take a look at the Clemson Extension Corn Production page.
Fungicide recommendations for corn can be found here on pages 62-64: UGA Corn Pest Management