Electrostatic method to separate roots from soil

Complete removal of roots from soil samples is a prerequisite for most of t he chemical and biological analyses. A simple electrostatic method of separ ating roots from sieved, largely mineral soil substrates was optimized and examined by the addition of C-14 labeled fine roots to sandy, silt loamy an d clay loamy samples. Depending on soil texture, between 40% and 50% of fin e roots can be removed from 100 g of sieved soil in less than 10 minutes. T he root-free soil substrate and the extracted roots can be used for analyze s or experiments immediately after the separation. The proportion of the mi neral particles remaining in the root fraction depends on duration of separ ation, distance between the charged plate and the sample, and soil texture. The proportion of separated mineral particles is about 90%-95% (w/w) in sa ndy and 70%-85% in silt loamy and clay loamy substrates. The electrostatic method of root separation may take place before the analysis of C-t and N-t contents, and is suitable for soil samples preparation for incubation expe riments.