Carnivorous plant often waterlogged, which favours the production of toxic ions such as ammonium, and its pH is an acidic 4 to 5. Ammonium can be used as a source of nitrogen by plants, but its high toxicity means that concentrations high enough to fertilise are also high enough to cause damage. However, the habitat is warm, sunny, constantly moist, and the plant experiences relatively little competition from low growing "Sphagnum" moss. Still, carnivores are also found in very atypical habitats. "Drosophyllum lusitanicum" is found around desert edges and "Pinguicula valisneriifolia" on limestone (calcium-rich) cliffs. In all the studied cases, carnivory allows
What Is and What Should Never Be and What Should Never Be" was performed live at Led Zeppelin concerts between 1969 and 1973. A live version taken from a performance at the Royal Albert Hall in 1970 can be seen on the "Led Zeppelin DVD". Another was included on disc two of the live triple album "How The West Was Won". Two more versions were included in BBC Sessions. What Is and What Should Never Be "What Is and What Should Never Be" is a song by English rock band Led Zeppelin. It was written by Jimmy Page and Robert Plant and was included as the second