Salmonella-Shigella plates. Salmonella-Shigella (SS) plates are used to detect bacterial contamination on raw meat. Salmonella-Shigella agar plates contain lactose, bile salts, ferric citrate, and neutral red.The bile salts select for Gram-negative bacteria.almonella-Shigella plates. Salmonella-Shigella (SS) plates are used to detect bacterial contamination on raw meat. Salmonella-Shigella agar plates contain lactose, bile salts, ferric citrate, and neutral red.
The best time to prune them is in early spring, just before they put on their growth spurt. You can do minor shaping and pruning at other times of year, too. Test Garden Tip: Save on holiday decorations by snipping a few branches for winter holiday greenery.
An excellent time to prune oaks is February and March. If possible, avoid pruning deciduous trees in the spring as they are leafing out. At this time, the tree's energy reserves are low and the bark slips or tears easily.Another poor time to prune is during leaf drop in the fall.f possible, avoid pruning deciduous trees in the spring as they are leafing out. At this time, the tree's energy reserves are low and the bark slips or tears easily. Another poor time to prune is during leaf drop in the fall.