The 2006 Louisiana cropping year has been a tough one. Weather woes, rust findings and disease and fertility problems have been seen. Harvest is taking place over much of the state and yields are mixed.
For grain sorghum, there is nothing but positive news. We had some disappointing yields in fields which received less than an inch of rain during the growing season, but overall the crop has been impressive. Most fields have triple-digit yields thus far and have averaged 110 to 120 bushels per acre. Some have been in the 130 to 140 range.
Because of the exceptional year, some producers are thinking about increasing grain sorghum acreage slightly for 2007.
The biggest advantage grain sorghum has over other crops is drought tolerance. In a year like 2006, it definitely had an advantage.
Corn also had a decent year considering what the crop has gone through. The big news right coming out of central Louisiana on dryland acres is that most folks are cutting in 170 bushels per acre or more. That is phenomenal considering the lack of rainfall.
Corn’s water use is maximized during kernel fill and we did have some rainfall during that time.
Perhaps the biggest help this year was cooler temperatures and favorable weather during pollination.
There have been few other problems with corn this year. In northeast and northwest Louisiana, fields that were not irrigated yielded much lower than those that had been irrigated.
I noticed that specific fungicides and a particular foliar feed in some cases increased yields in non-replicated strip trials. I am not recommending that we all put the products out on our corn in 2007, but there is enough positive yield enhancement from a couple of products to continue research with them.
Soybean harvest is in full swing except in southwest Louisiana. The crop in the southwest still looks good, but diseases and insects are being found and treated.
Many different things are going on in central Louisiana: mineral deficiencies, red crown rot, charcoal rot, aerial blight, pod and stem blight, anthracnose, folicure damage and rust. Add insects and drought stress, and it is difficult to determine which was the main cause of problems. In most cases, it is a combination of several of factors.
Asian soybean rust has been confirmed officially on soybeans in Rapides, Avoyelles, Natchitoches and Tensas parishes and unofficially in St. Mary and Iberia parishes. No new confirmations on kudzu have been reported in the past couple of weeks.
Weather conditions are still unfavorable for the disease to spread over a very wide region.
Why is the disease not spreading? Weather is the main reason. It has been drought-like with very little rain over most of the state and very hot.
Also, before the first rust was confirmed in Alexandria, most of the soybean crop already had been treated with a stroby-based product such as Quadris or Headline. In some cases, producers had applied triazole mixes such as Quilt or Stratego. Because of the applications and the late growth stage of the majority of the crop, we did not see much spread of the disease.
Two weeks after the initial find, fields were being desiccated for harvest. We are harvesting between 5,000 and 8,000 acres a day, reducing the area the disease can spread to.
Southwest Louisiana and south central Louisiana were planted much later due to weather conditions. Some producers planted as late as July 14. The crop is very spaced out. Most remaining late beans are approaching R5 and are not out of danger yet, but they have been sprayed with stroby/triazole mixtures.
We have been very conservative in recommending a blanket second application. The incidences of confirmed rust have been few and a second application may not be warranted in some situations.
Treat each field individually, especially when money is tight. Rust is just another disease in the complex. Aerial blight and cercospera have done much more damage to the Louisiana crop this year than rust has.
Mid-south universities had limited data on the efficacy of treating for secondary diseases. Exceptional fungicide research now is being conducted with many products and timings this year, and we will have that data for you in the coming months.
Yields for soybeans harvested thus far have been mixed.
Northeast Louisiana, which usually leads the state in yield, suffered for moisture season-long, and yields there have been impacted, especially on dryland fields. Yields are ranging from about 20 to 60 bushels per acre across irrigated and non-irrigated fields.
Central and northwest Louisiana yields range from 20 to 45 bushels per acre.
Northwest Louisiana is simply burning up. Red River, Natchitoches and Grant parishes are extremely dry and crops there have been impacted.
The most recent problem statewide is paraquat being applied too early. I have noticed fields in many parishes where paraquat had been applied and the beans were not all the way out of R5. We will have to try to address this problem in the future. Green bean syndrome makes timing the application correctly more difficult. Beans should be at R7 at least before a desiccant is applied.
Jim Griffin is in his second year of desiccant timing research.
The 2006 crop year is almost over. We soon will have data from the verification fields, crop demos, and commercial variety trials on the LSU AgCenter Web site. Continue to check with local county agents about data available to make good decisions when booking seed for 2007.
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