from the University of Wisconsin study:
Humate and Humic Acid
By Dr. Wayne R. Kussow, Department of Soil Science,
University of Wisconsin - Madison
The single research report in my files is fora study in which 14 “non-nutritional growth enhancers” were applied to a creeping bentgrass putting green. Several humic acid and humate products were among those tested. The focus of the study was the effects of the products on rooting and root development. Data averaged over all rooting depths for the entire growing season revealed that non of the products significantly affected bentgrass root length or root numbers.
from the NC State study that I assume he is quoting from:
Influence of Humic Substances on Rooting and Nutrient Content of Creeping Bentgrass
R. J. Cooper *,
Chunhua Liu and
D. S. Fisher
In sand culture, humate incorporated to a depth of 10 cm stimulated a 45% increase in root mass at the 0- to 10-cm depth and a 38% increase in root mass at the 10- to 20-cm depth compared with the control. Incorporation of granular humate increased maximum root length 15% compared with non-treated turf in sand culture.