A website from UGA Cooperative Extension

This is the time of year when I begin to get asked “What’s the Georgia crop going to be this year?” . That has always been a loaded question and I have come to the conclusion that there’s not a lot of good found in throwing a number out there. At best, its an educated, but still largely, a wild guess. So I am not going to put a number on the crop. What I will tell you is that the 2021 crop, according to USDA numbers, was officially 88.6 million lbs, the 2022 crop was 125.5 million lbs. Based on what I see out there, the 2023 crop set would fall between these two. It looks bigger than the 2021 crop and nowhere near as large as the 2022 crop. However, we are seeing tremendous scab pressure at the moment and it is happening at the worst possible time for the pecan crop. Almost daily rainfall for the last week and a half and rain forecasted daily for as far out as we can see during June as the nuts begin rapidly sizing is a recipe for disaster on susceptible varieties. This will almost assuredly lead to additional scab losses for the Georgia crop. The other thing that plays into the size of the crop is the vast pecan acreage we’ve planted over the last 13 years or so. Many of these orchards, even those planted 6-7 years ago are contributing significantly to the state crop now so if you are a grower who’s acreage is composed largely of old trees, which seem to be off across the state for the most part, you are going to think its a bad off year. We need to recognize that the younger trees are carrying the weight for the Georgia pecan crop now and this shifts our scale upward for both on and off years. Also, pecans are a global market at this point. The size of Georgia’s crop still certainly matters to the market and where prices fall out but with Mexico and South Africa in the picture, it doesn’t set the tone for pecan prices as much as it once did. Some people may take issue with this, but its a fact whether we like it or not. At this point the Georgia crop size is going to be determined by the amount of scab we end up with and how well growers are able to control the disease.

Managing Scab in Extreme Conditions

There are a few things to keep in mind when trying to control scab in the apocalyptic scab conditions we are dealing with.

  1. The best options for scab control during the nut sizing period from June-August will be Miravis Top, Miravis Prime or Dodine (Elast). Growers should rotate either Miravis Top or Miravis Prime with some form of Dodine, whether you use dodine alone or tank mix it with Tin. Under regular conditions, you likely won’t see a lot of difference in Miravist Top and Miravis Prime. Under the extreme conditions we are experiencing, I would say that if there is a scenario where the use of Miravis Prime would be justified, this is it. However, both products are excellent on nut scab. But DO NOT FAIL TO ROTATE these products with a Dodine application of some sort. If you use one of the Miravis products back to back to back, you are going to abuse this excellent product and at some point we will not get hte benefit from it that we currently enjoy. I know growers will be tempted to want to use “the best possible product” every time but I cannto over-emphasize the need to be good stewards of the chemistry we have for scab control. The dodine chemistry remains excellent and growers should not be afraid to rotate this with the Miravis products.
  2. Tighten spray intervals. If you do not tighten your interval during extreme wet weather, it will not matter what fungicide you use. I know this is hard to do when it is raining daily but you have to keep the nuts covered and they are growing very rapidly. If you spray today there will be tissue there in 5 days that was not covered by today’s spray so in wet weather, frequent applications (every 7-10 days) are required for effective scab control on susceptible varieties.
  3. Use a surfactant with certain products. Under dry or even normal conditions, I don’t think you get any economic benefit from using a surfactant. However, in wet weather, a surfactant can be a big help with products like Miravis Top or Miravis Prime because they may help the fungicide to stick on the nut surface better, spread over the nut surface better, or move into the nut tissue faster (depending on the surfactant used). All of this can help under wet conditions . The Miravis products should ideally have at least 5-6 hours of drying time before a rain. A surfactant may possibly give you a little room for error and speed that up. Dodine has surfactant properties itself, so a surfactant is not necessary with Dodine, however since it is a pure protectant, dodine (and tin) need 24 hrs for maximum rain-fastness. With any product, if you get rain within an hour of spraying, you need to re-spray eveything you put out in the last hour as soon as you can.

Stuart Issues

We are seeing some very strange things out there with Stuart trees. The most puzzling is a leaf drop that seems to be very common over in East Georgia, almost exclusively on Stuart, or at least that is the variety it is most often occuring on. This has been occuring for several weeks and we have bouced around ideas regarding scab and stem phylloxera, among other theories but htere seems to be no real pattern. The leaves are sometimes scabbed heavily and sometimes perfectly clean. Sometimes they are scorched and more often, not. We are investigating this issue to try and find out what is going on and will keep you posted here on any conclusions that are drawn.