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.
Last Updated: CORVALLIS, Ore. - You can prune an apple tree any time of the year without hurting it, but late winter, just before spring, is probably best. The worst of the cold weather is past, so you won't be subjecting the fresh cuts to severe icing, but you'll still be able to influence the tree's spring growth.ast Updated: CORVALLIS, Ore. - You can prune an apple tree any time of the year without hurting it, but late winter, just before spring, is probably best. The worst of the cold weather is past, so you won't be subjecting the fresh cuts to severe icing, but you'll still be able to influence the tree's spring growth.