EFFECTS OF RESIN FOAM SOIL AMENDMENT ON THE GROWTH OF TURFGRASS SUBJECTED TO DIFFERENT COMPACTION LEVELS

A field experiment was conducted to evaluate the effects of a foamy soil amendment (urea formaldehyde resin foam, [F]) on soil physical properties and turfgrass growth when subjected to increasing compaction levels. Four months after sod transplant three compaction levels were applied with the use of a self-propelled cylinder (54 KPa): a) no pass (0X), b) moderate 4 passes (1x), and c) high-12 passes (3x). The effects of compaction on turfgrass growth were evaluated by measuring clipping and root dry weight. In addition soil penetration resistance, saturated hydraulic conductivity (K_sat) and bulk density were also determined. Top growth of the turf sward was affected only by compaction and not by soil amendment incorporation. Non-compacted turf had the highest total clippings dry weight. At 1X compaction, F slightly improved top growth compared with the non-amended profiles, while at 3X compaction turfgrass provided the lowest clipping dry weight, regardless of substrate. Root dry weight was not affected either by the substrate or by the compaction level. In contrast, the strength of the substrate was found to be elevated both at 1X and 3X compared with the control. Bulk density increased more in the non-amended soil compared with the amended substrates when subjected to moderate and high compaction levels. K_sat exhibited a more pronounced decrease in compacted soil compared with the F-amended soil. In general the addition of F amendment improved compaction resistance of soil especially in moderate compaction levels.