The Effects of Silicon Applications on Wear and Drought Stress of Cool Season Turfgrass.

The ability of turfgrass to maintain quality and functionality during use and drought stress are fundamental to almost all turfgrass environments. A possible mechanism to increase wear and drought tolerance is through the use of supplemental silicon (Si) application. Until recently, Si has received little attention for its role in crop physiology or performance. 

While it is recoverable within the plant it is not recognized as an “essential” plant growth component.  Si is the second most abundant element in the Earth’s crust; however the majority of soil-Si is bio-geochemically inert. Plants absorb Si exclusively as monosilicic acid, H₂SiO₄ which may be depleted from many soils due to crop harvest, erosion or heavily weathered soils.  Soils in Rhode Island are largely formed over granite materials, being highly resistant to weathering releasing little soluble-Si. 

The objective of this research was to provide increased knowledge and insight to how Si applications might affect cool season turfgrass wear tolerance, from foot and vehicular traffic, and drought tolerance.  Four treatments were applied to raise the ambient soil-Si by a minimum of 20%. The supplement treatments included ash of a known Si accumulator, bamboo leaves, wollastonite, PlantTuff silicon fertilizer, and Stabilized Silica Technology 28% Silica liquid fertilizer. Trials were conducted at three sites on a sandy-skeletal, mixed, mesic Typic Udorthents practice green with approximately 50,000 rounds per year, a coarse-loamy, mixed, active, mesic Aquic Dystrudepts fairway with approximately 12,000 rounds per year, and an urban disturbed soil on campus at the University of Rhode Island that had Kentucky bluegrass sod laid in 2012. Plots were 3ft x 3ft, replicated four times in a randomized complete block design.  Quality ratings, color and cover, were visually estimated using a 1 to 10 scale, where 1 = poor, 10 = excellent, and 7 = acceptable.