Entomology
By Mark Abney,
The dry conditions in May could set peanut fields up for pest problems in June and beyond if rainfall continues to be scarce. Lesser cornstalk borer (LCB) is the most common and severe dry weather pest of peanut. Scouting and timely decision making are the keys to managing LCB in peanut. Preventative insecticide applications are not recommended. Even in LCB outbreak years, not every field will need to be treated. We do not have to prevent infestations from occurring, we just have to find and treat them in a timely manner. Two spotted spider mite is another dry weather pest, but it usually appears in peanut later in the summer. Finding mites in cotton in June is a good warning sign that problems in peanut are just around the corner. Mites very often occur in large numbers in peanut fields where pyrethroid insecticides have been applied. Avoid pyrethroid insecticides in non-irrigated peanut fields to prevent flaring mites. While we do not usually see treatable populations of mites in peanut in June, the decision to apply a pyrethroid in June or July can dramatically increase the risk of infestation later in the season. Folks will begin to see some foliage feeding caterpillars this month, and while populations rarely reach threshold levels in June, it is wise to scout regularly.
June Expected to be Wetter Than Normal; Tropics Quiet So Far
By Pam Knox, Agricultural Climatologist,
Now that the Bermuda high has shifted back to the east, the Gulf of Mexico is sending more moisture our way. This means that we should see a return to more regular showers for the foreseeable future, with up to 4 inches predicted in some places over the next three weeks. The Climate Prediction Center gives us slightly better odds than usual of above-normal rainfall in June and in the June-August period. We need it! As you know, the start of the Atlantic tropical season was June 1, although we had one storm, Ana, in May, that developed over the central Atlantic Ocean. Most of the storms in June develop over the Gulf of Mexico and the Caribbean, where the water is warmest, but nothing looks imminent for the beginning of June. Mid-June may see some increased activity, but of course at this point we don’t know where any storms that develop might go. September through October is also leaning towards wetter than normal conditions, based largely on the expected active tropical season. The rainfall we actually get later in the summer will depend in large part on where the tropical storms and hurricanes go. Last year, it seemed like they all went over Louisiana, dropping a lot of rain to their east along the Gulf Coast, but this year, even if active, could be quite different and Texas or the East Coast could be the “lucky” recipients of the rain. Based on our neutral ENSO conditions, warm sea surface temperatures, and other factors, this year is expected to be more active than normal again, although not likely as busy as last year, which had a record 30 named storms.
Peanut Stands
By Scott Monfort,
There have been very few issues regarding poor plant stands. Based on my conversations with the personnel at the Georgia Department of Ag seed lab in Tifton and recent field visits, the peanut seed quality based on the samples they received was very good to excellent for much of the year. This does not mean there won’t be occasional situations of poor seed quality or problems with the weather. I do expect seed quality to start going down the further we go into June. Planting in June always presents a few problems for growers. Most of the time growers are planting in June due to increased acreage or due to weather (like the lack of rain in late May). The hot and dry conditions are finally lifting in many parts of Georgia, but the rains have not been wide spread. With this in mind, growers will likely have stand issues in June either from planting in field with limited moisture, or have seed with diminished seed quality.
Early to Mid-Season Irrigation for Peanuts
By Wesley Porter, Extension Precision Ag and Irrigation Specialist
& David Hall, Extension Water Educator
Similar to May of 2019 which was very hot and dry, we had some very hot and dry weather during May of 2021, dry enough that we had to apply some small irrigation events to our young peanut crop. Luckily, during the first week of June, we started receiving some sporadic rainfall across the state. Due to the hot and dry periods planting dates have been strung out and, in many areas, early June peanut plantings will occur. Keep this in mind when you are looking at the water use for your crop, as a single farm may have peanut maturities spread across a month’s timeframe.
Keep track of the graph below or use our Irrigation Reference Guide for Corn, Cotton, Peanuts, and Soybeans | UGA Cooperative Extension in the field throughout the month of June and stay on top of your irrigation requirements. If you planted your peanuts during late April or early May, most of these earlier planted peanuts will be beginning to bloom, so expect water usage to gradually increase. Peanuts will begin flowering on average around 40 days after planting.
Remember the water requirement is IRRIGATION and RAINFALL! Also, consider irrigation efficiency especially on hot dry days. A typical pivot is 85% efficient, so don’t under-irrigate, but at the same time don’t over-irrigate either. Research has shown reductions in yield just as significant for over-irrigating as for under-irrigating. Good record keeping and a sound irrigation scheduling strategy can aid significantly in increasing profitability in multiple ways, including Approximate Peanut Age reductions in irrigation applications, correlating to reductions in energy requirements, and potentially increases in yield.
A couple of quick reminders regarding irrigation of peanuts. Early irrigation applications can tell you very valuable information regarding your water application uniformity. If a mobile irrigation test was not conducted, pay close attention to the way your soils dry out after an irrigation application. If your peanuts were planted into conventional tillage, this will be easy to see especially prior to full canopy closure. Visible bands drying out quickly, or bands staying wet for longer periods are signs of poor uniformity. Go to these areas of your pivot and address them now. As the peanut canopy develops and laps, the obvious signs will not be visible. Hot dry weather makes it easy to see if your pivot was working properly due to the extreme heat and drought. The under applying nozzles are easy to see by the evidence presented as stressed crops in bands under the pivot. Lastly, if you are using soil moisture sensors and have “weighted” the sensors, now is the time to reweight the sensors because of increased root development and crop progression. Consider using other tools in conjunction with your moisture sensors. Irrigator Pro (https://irrigatorpro.org/) integrated with a soil moisture sensor system through UGA trials has repeatedly shown higher yields than the checkbook method. The Irrigator Pro website includes a step-by-step video tutorial on how to download the app.
June Peanut Pointers
By Bob Kemerait,
For several reasons, June is a critically important month for disease management and, sometimes, for nematode management as well. Based on planting date, most of the peanut crop will be between 30 and 45 days after planting at some point in June.
1. Fungicide programs for management of leaf spot diseases (except for the earliest and latest-planted peanuts) are typically initiated during the month of June. Leaf spot programs should begin closer to 30 DAP when A) the field is at higher risk to leaf spot based upon results from Peanut Rx, and/or when B) fungicides to include chlorothalonil, Mazinga, chlorothalonil + Domark, and chlorothalonil + Alto are used as the first fungicide application.
2. Fungicide programs for leaf spot management can safely begin closer to 45 days after planting when A) the field is low-risk to leaf spot diseases as determined with Peanut X, B) fungicides such as Priaxor, Lucento, or Aproach Prima are used in the opening fungicide application, or C) Velum or Velum Total is used in-furrow at planting.
3. Growers should avoid, if at all, possible initiating a peanut fungicide program later than 45 days after planting.
4. The “backbone” of most fungicide programs for control of white mold does not begin until approximately 60 days after planting; however growers often start earlier, especially when short rotation increases risk to disease. Effective ways to begin a white mold program within the first 45 days after plantings are to, A) apply Proline (5.7 fl oz/A) in a narrow band over the peanuts, B) include tebuconazole or azoxystrobin with your first leaf spot applications, or C) adopt Elatus or Excalia programs that begin as early as 30 days after planting.
5. Applications of Propulse can be made as early as 45 days after planting to fight leaf spot, white mold, and to supplement earlier nematicide applications for control of nematodes. The “Good”: Timely fungicide applications (before disease is established) are a critically important tactic for controlling disease. Starting your leaf spot program on-time, often in June, sets the stage for a successful disease management program and best yields. The “Bad”: Getting behind in a fungicide program early in the season may allow disease to become established that is difficult (if not impossible) to manage later in the season. While I know some growers wait until 50-55 days after planting to begin their program, I strongly advise you to not wait later than 45 days after planting and to begin as early as 30 days after planting in a number of situations.