1993 Volume 22 Issue 1 Pages 29-36
As the first step to develop a turfgrass production system, urethane-foam has been chosen to culture turfgrass seedling. It has been confirmed that urethane-foam can culture the turfgrass seeding just as well as sand of conventional culture medium does, and urethane-foam sod provides superior mechanical handling proerity.
Futhermore, flexible polyurethane-foam F, semi-rigid polyurethane-foam SR 1, SR 2 and S have been developed with taking considerations of the degradation of urethanefoam and the soil hardness of turfgrass with urethanefoam as culture medium after transplantation.Urethane-foam F, SR 1 and SR 2 with thickness of 5 mm and 10 mm were used to culture Manilagrass and, F and S with thickness of 5 mm and 8 mm were used to culture Pencross, corn paring to sand in both cases. A series of experiment were conducted and the results are as follows:
1. Seeding growth
There was no significant difference at p<0.05 in dried shoot weight and hueangle of shoot in all experimental blocks. However, it was noted that the urethane-foam with thickness of 8 mm or 10 mm produced more dried shoot weight than 5 mm experimental blocks did.
2. Sod tensile strength and sod mass
The tensile strengths of Urethane-foam sods were 1.7-3.8 and 2.4-6.3 times that of sods for Manilagrass and Pencross respectively.
The masses of urethane-foam sods were about 70% and 50% of sand sod for Manilagrass and Pencross respectively.
3. Root growth after transplantation
For both Manilagrass and Pencross, the turfgrass root of urethane-foam sod grew just as well as sand sod's. It was observed that root Manilagrass and Pencross grew 10-15cm underground in 10 months after transplantation.
4. Soil hardness
For flexible urethane-form F, the soil hardness were 0.51-0.65 kg/cm2 which was much less than 1.12-1.32 kg/cm2 of sand experimental blocks in six months after transplantation. However, SR 1, SR 2 and S blocks provided a soil hardness of 1.09-1.32 kg/cm2 wich was equivalent for that of sand blocks.
5. Degradation of urethane-foam
Semi-rigid polyurethane-foam S degreded ultimately right after transplantation. The reduction rate of F, SR 1 and SR 2 were 31.1%, 55.4% and 61.1% with trampling in six months after transplantation, which were much higher than 7.1%, 19.5% and 28.7% without trampling respectively.
