Yesterday Jerry Moody and I evaluated some treatments for rosette bud mites that a grower made with a couple of new products -- Movento and Mavrik. Movento, if you will recall, is a new systemic made by Bayer. Last year it looked like one of the trees that had rosette buds recovered after a spring Movento treatment. Mavrik Aquaflow is a synthetic pyrethroid that Jerry Moody has had a couple of growers use for rosette bud mites. The Avery County grower used a mistblower to apply the products. To date we've never seen any mistblower applications work that well for rosette buds, though some folks have gotten good enough control with a mistblower using Dimethoate. The hope was that the Movento would work better through a mistblower since it is such a good systemic.
Of course the buds for next year are just forming now, and it is too early to go through a field and pick out the rosette buds. So Jerry and I randomly pulled some new growth on trees that had rosette buds, and I looked at them under the microscope to see if any mites were present in the developing tissue.
The results... Not going to say yet. Sorry. Still too preliminary. But I would like to share this photo I took at the Watauga Extension office of a rosette bud forming. This is a shot of a bud sliced down the middle from top to bottom. You can see that there is a cavity forming where the shoot should be and about 10 rosette bud mites -- and maybe even an egg. The same photo is seen below with everything labeled.
And obviously, since I was finding some mites, one of the products didn't work -- but one seemed to! I think I'll go back next week and collect more samples and spend some time taking photographs which I'll share on my blog. It will probably be mid July before I can give the results of this little study after the rosette buds have clearly formed and I can see throughout the block how well things are working. So stay tuned.