I've been getting a few questions today regarding FireWall 50 WP as an alternative to Harbour for streptomycin, so I thought I'd send out an extremely brief post about the product. Firewall 50WP is streptomycin and growers in other states have been using it for a few years I believe. The biggest difference between this product and those that you may be more accustomed to such as FireWall 17WP or Harbour is the percentage of streptomycin in the product. Harbour contains 22.4% strep, whereas Firewall 50WP contains 66.8% of the active ingredient. Thus, if you go out and spray 8 oz of FireWall 50WP you may get a bit of burning on your leaf margins!

So, if you are spraying FireWall 50WP for fire blight, apply 2.67-3 oz/100 gal in protective mode and if you need some kickback action, 5.3 oz/100 gal would be reasonable. If you are spraying Harbour or a different strep product with the same % active ingredient, do the 8 oz or 16 oz/100 gal rate. Hope this helps and happy spraying!!