Portlethen Moss millennia of evaporation, further intensifying the soil acidity, fueled by organic matter decaying, with little drainage outlet. A layer of sphagnum moss would have developed at the benthic level of the bog, and additional sphagnum layers floated in mats atop the bog. At an intermediate level of evolution, thick peat layers formed from decay and carbonisation of the rotting sphagnum. Generations of carex and juncus flourished, leading to further decay of these materials and eventual heightening of the organic mass. Finally, secondary vegetation took root in the spongy sphagnum mats adding greater biomass to the bog.In some cases the heavy
Sphagnum taken during the harvesting of "Sphagnum" to ensure enough moss is remaining to allow regrowth. An 8-year cycle is suggested, but some sites require a longer cycle of 11 to 32 years for full recovery of biomass, depending on factors including whether reseeding is done, light intensity, and the water table. This "farming" is based on a sustainable management program approved by New Zealand's Department of Conservation; it ensures the regeneration of the moss, while protecting the wildlife and the environment. Most harvesting in New Zealand swamps is done only using pitchforks without the use of heavy machinery. During transportation,