Environmental Science and Management


Sullivan, W., Michael

Advisor Department

Plant Sciences and Entomology




This poster examines the effects of various silicon treatments on drought and wear tolerance to cool-season turfgrass. Silicon has been known to increase tolerances to abiotic and biotic stresses including wear and drought stress. Silicon is the second most abundant mineral in the Earth's crust, however the majority is inert and unavailable for plant uptake. The plant available form is monosilicic acid and the goal of this research was to raise ambient soil levels for plant uptake. Silicon sources included an organic source (Bamboo - a hyperaccumulator of silicon), a liquid fertilizer (SST 28% Silicon), a granular fertilizer (PlantTuff silicon fertilizer), and a powder (wollastonite).

The results of this study are inconclusive due to limitations of sites (the previous use of silicon fertilizers for five years at one site, inadequate time at one site, and high bulk densities at the third site). In addition, there is need to continue applications to accumulate enough monosilicic acid to make significant differences.


Turfgrass, Silicon, Drought Tolerance, Soil Applications, Bamboo


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 monosillicic 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% 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.