It’s been a beautiful scene these past couple of weeks. However, the early bloom has made it difficult to get out the delayed dormant application of oil for scale management (or at least it did for me!). As such, if you were like me and missed the delayed dormant timing, especially in blocks with chronic scale issues, then I would suggest focusing on crawler management.
Once San Jose scale crawler activity begins to increase (see below for timing), consider management with insect grower regulators, such as Esteem (6 oz/acre) or Centaur (34.5 oz/acre). Alternatively, when targeting the scale crawlers, Venerate XC (2 qt/acre applied twice over a 7 day period; 4 qt total) or diatomaceous earth (i.e. Celite 610 @ 10 lb/acre applied 3-4 times bi-weekly) have both showed efficacy at suppressing San Jose scale.
If management occurs later, once the crawlers have already settled and/or you cannot find active crawlers in a block with a history of scale, it may be best to treat with Movento (9 fl oz/acre). Note that Movento should be applied once the trees have substantial leaf area, flushing new growth, and should be tank mixed with an adjuvant that has spreading and penetrating properties. Anecdotally, I have applied Movento late April and have had good success.
In terms of scale crawler timing, following the degree day (DD) timing starting at February 1st using a base of 51oF and a max of 90oF, at this point last year in Fort Valley we had accumulated 222 DD and this year we are at 348 DD (UGA Weather). I anticipate the first main peak of crawler activity to occur at approximately 700 DD since Feb. 1, which which is still a few weeks away, but I will update the blog as we get closer to the appropriate timing.
Take care, everyone!