separation of weed seeds from soil samples

[Henk_Melenhorst]

Physical SEPARATION of WEED SEEDS from SOIL SAMPLES.

The laboratory for soil and plant analysis in Oosterbeek, The Netherlands and 
the department of Theoretical Production-ecology of the Wageningen 
Agricultural University study the possibilities to separate arable weed seeds 
from a soil rich of organic material for laboratory routine analysis. In 
principal the separation of seeds from mineral soils can be executed 
sufficiently. Physical techniques to separate seed from the soil mineral 
fraction by a sieving/flotation procedure are available and described in 
several publications.

The separation of the seeds from organic soils causes problems difficult to 
solve. Essential is the lack of diffrences in physical properties of seeds and 
other organic material in the soil.

Who has solved the problem of finding seeds in organic soils in a reliable and 
reproducable way?

Have people concluded and published that physical separation techniques are 
inappropiate?

Jolanda Schrauwen