New pesticide labels available to help control pruning wound infections
Topsin® M WSP and Rally® 40WSP now have 2EE labels to protect pruning wounds on almonds (and other stone fruit trees and/or grapes) from canker disease infection. These products should be especially helpful in protecting young trees where disease infection of relatively large pruning cuts may cause extensive damage. ----Canker diseases listed on the Topsin®M and Rally® labels----
| Topsin®M WSP | Rally® 40WSP |
| Eutypa | Eutypa |
| Cytospora | Cytospora |
| Calosphaeria pulchella | Calosphaeria pulchella |
| Lasiodiplodia theobromae | Lasiodiplodia theobromae |
| Botryosphaeria | Botryosphaeria* |
| Phomopsis | Phomopsis* |
*suppression, only The labels are very similar in many regards. The following are recommended on both labels:
- Application within 24 hours of pruning is highly recommended.
- Assure complete coverage of all cut surfaces.
- Add a registered spray dye to better assess coverage.
- Additional application after about 2 weeks, especially if rain, irrigation, or high humidity occurs.
- Product combination (tank mixing) for best results and resistance management (Topsin M is a FRAC 1 fungicide, Rally a FRAC 3, and both have single site – high resistance risk – activity).
- Use of an organosilicone surfactant to improve pesticide penetration into pruning wound surfaces. (It is up to the grower to select and use a crop-safe organo-silicone with these products on pruning wounds).
There are some differences in the labels that limit how they can be used separately or combined.While the labels recommend tank mixing for best results and resistance management, consider the following:
- The Rally label does not allow painting the product on pruning wounds, while the Topsin M label does allow painting
- In addition, at the labeled rate (1.5 lb/acre), Topsin M is limited to 2 applications/year (max of 3 lbs/acre/year), while Rally is permitted a max of 3 applications/season (max of 1.5 lb/season).
- Therefore, if the two products are combined, painting is out and only 2 applications are allowed.
The similarities and differences on these two labels, intended for roughly the same purpose and target organisms, are a reminder of the importance of reading the label carefully and following it when applying the material. [It took an observant colleague to point out to me that painting was NOT on the Rally label…].The 2EE labels (current as of September 2017) can be read online.Topsin-M: http://www.cdms.net/ldat/ld4EK010.pdfRally: http://www.cdms.net/ldat/ld9M8019.pdf