7. Are earth worms and other soil organisms affected?
Our saturated steam provides rapid penetration and transfer of heat to any vegetation which the applicator heads pass over. It is non selective on any organisms. A benefit of our economical use of saturated steam and boiling water is that it does not penetrate more than about a ¼”, 5mm, into the soil. This has great effect on the crowns of weed species but little effect and no lasting impact on either the roots of your perrennial crops, trees, vines etc or your important soil organisms. Earth worms tend to be found lower down in the soil profile, unless there are very wet surface conditions. Our observation is that the destroyed weeds quickly become detritus providing food for a rapid repopulation of soil organisms which helps builds a humus layer in your soil.
To kill most plant pathogens and beneficial microbes such as Rhizobium bacteria and mycorryhizal populations the soil temperature must be “raised and held at between 60 – 80ºC for 30 minutes.” ( KA Hendreck & N. Black (1994 Revised Edition) Growing Media for Ornamental Plants and Turf. Randwick: University of NSW Press.) With our SW weed control on average only the top ¼”, 5mm of the soil directly under the head is heated for a couple of minutes.