After a short stretch we are once more looking for rain. Forecast anticipates possibly mid next week we may see some.

The combination of warmer temperatures and stress from dry conditions for rainfed fields is a reminder that if our fields have some history of stem rot/white mold disease, we can proactively protect them during our earlier fungicide applications. This can be as simple as adding tebuconazole in with the 45-day spray or coming in earlier 30/35 DAP with Elatus/Excalia/Priaxor. Not all fields need the extra attention, but it is a helpful tool at our disposal where we are looking for additional management. Likewise, earlier applications are less subject to canopy interference of spray penetration/ground deposition. Rain is our friend for many things including fungicide wash in, but its contribution rapidly drops off with increasing time after application. Two days after an application, rain will help some but is at that point more modest than monumental. Rain-in the day of application or a day after improves wash in, but at the expense of foliar leaf spot coverage/control. A persnickety predicament, or rather, a reminder of fine tuning one way or another. If we are coming due for an application where soil disease control is a priority and we can wait a day to two/three days to take advantage of a coming rain we can consider doing so (though we are familiar with the no-guarantee nature of forecasts). This is more helpful later in the season when canopy size is larger. However, an application without rain is better than no application at all. We cannot wait indefinitely, and we keep in mind the importance of effective leaf spot management at the same time.

Attached are pictures from a test we are conducting this year comparing powder seed treatment to polymer seed treatment. A humble single data point in time, but so far the powder treatment (Rancona V PD) has more plants up than the polymer treatment (Trebuset). It is not uncommon for early differences to later be softened or negated as additional plants emerge, and one data point does not answer all questions. Time will tell, as will later yield results.

Land plaster is best applied before plants start pegging, swelling, and pod filling in earnest. Applying around bloom (~35 DAP) is a good rule of thumb. Heavy rains after application can increase leaching, thus earlier application is not always better in this case. From a survey we conducted in '21 and '22, gypsum applied after stand establishment and near bloom between 30 to 40 DAP had similarly high yields compared to no gypsum application (1700 lb/A less yield).

As fields near 45 DAP, boron (0.3 to 0.5 lb boron/A) can be added as needed (soil test < 0.4 lb) with the fungicide application, if it has not gone out already with an earlier herbicide application.