Forest Fertilization

INFORMATION RELATING TO THE POSSIBLE USE OF
HUMANURE (human feces) AND URINE FOR FOREST FERTILIZATION

It is always best to rely on gradual, long-term soil management programs and on natural (organic) methods ("feed the soil, not the plants") of maintaining soil organic matter and soil health and productivity. In some cases, however, the survival of individual planted trees or stands of trees may require that one or more chemical elements be added to the soil at the time of planting or at some later time. For example, fertilization may be essential when re-foresting abandoned agricultural land, or land abused by off-road-vehicles or surface mining.

Chemical elements sold in commercial fertilizers are expensive in terms of monetary cost to the user. More importantly, artificial fertilizers are expensive in terms of costs to the Earth since their production relies on non-renewable petroleum resources and their use involves a high probability of ecosystem degradation due to the low fertlizer uptake efficiency of plants and the resulting pollution of soil and groundwater.

Human feces ("humanure") and urine constitute serious waste-disposal problems especially in areas with high human population densities. At the same time, these materials are rich in chemical elements that are essential to plants, and humanure may function as organic matter to maintain the reservoir of soil humus that, in turn, controls physical and chemical processes and properties in soils.

The tabulated information presented below speaks for itself and argues strongly for an effort on the part of governmental and non-governmental organizations to develop the processing and supply technology, and the infrastructure, needed to allow humanure and urine to be used as fertilizers on restored forests and other such lands. Since edible plants are, in general, not grown on such areas, there would little danger of food contamination and disease spread via pathogens contained in the humanure or urine.

THE RESOURCE

  1. Appalachia - Science in the Public Interest Technical Paper No. 2. Of the 2.5 pounds of excreta that humans produce per day 2 lbs is urine and 1/2 lb is feces. Water makes up 75% of feces and 94% of urine. The rest is:

    Feces Urine
    Carbon - 40-50% Carbon - 11-17%
    Nitrogen - 5-7% Nitrogen - 15-19%
    Calcium - 4-5% Calcium - 4-6%
    Phosphorus - 3-5% Phosphorus - 2-5%
    Potassium - 2-5% Potassium - 3-5%

  2. Hole, F. And R.F. Heizer. 1973. An Introduction to Prehistoric Archeology. Holt, Rinehart, and Winston, Inc. NY. p. 251.
    Annual body wastes per 100 humans:
    915 lb nitrogen
    137 lb phosphorus
    55 lb calcium
THE NEED
  1. Pritchett, W.L. and R.F. Fisher. 1987. Properties and Management of Forest Soils. Wiley & Sons, NY. p.348.
    Fertilizer recommendation for nitrogen to be applied 2-3 times during a 25-30 year pine rotation:
    60-200 lb/ac nitrogen


    Fertilizer recommendation for annual application of nitrogen and for a single application of phosphorus at time of planting for hardwoods:
    80 lb/ac nitrogen
    40 lb/ac phosphorus