Water is the most frequently used substance for extinguishing of wildfires. Ones of the most commonly used additives enhancing the extinguishing efficiency are foaming agents. This article deals with the influence of foaming agents on germination of coniferous species. Foaming agents Moussol-APS F-15 and Sthamex F-15, foaming solutions of various concentrations were used for the tests. Germination of seeds of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was observed. The percentage of germinating seeds was recorded every 7 days. The results were evaluated in the form of graphs.

   When the concentration levels of foaming solutions ranged from 0.1 vol% to 0.25 vol%, their influence on germination of both coniferous species seeds varied from negligible to slightly positive. Subsequently, the negative effect increased considerably and with concentrations exceeding 1 vol%–1.5 vol% the germination of samples reached zero values. While foaming solutions of Sthamex F-15 showed less significant influence on germination of the Scots pine seeds, seeds of the Norway spruce were less influenced by foaming agent Moussol-APS F-15.
   Based on obtained results it is possible to recommend minimisation of foaming agents amounts, eventually application of substances with less negative effect on plants germination for extinguishing of wildland fires, in order to gain restoration of affected area as fast as possible.

Keywords: foaming agent, germination, wildfire (wildland fire), foaming solution