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.
(e-mail reference). A: Birch trees should be trimmed as little as possible and only when absolutely necessary (when there are dead or broken branches). You may want to trim after the leaves have fully expanded to cut down on excessive sap flow. Q: I have a birch tree that woodpeckers are pecking full of holes.e-mail reference). A: Birch trees should be trimmed as little as possible and only when absolutely necessary (when there are dead or broken branches). You may want to trim after the leaves have fully expanded to cut down on excessive sap flow. Q: I have a birch tree that woodpeckers are pecking full of holes.