FOR
Kar Wo Fertilizer & Seed Co.
Turf performance of the Macau Stadium
Prepared by:
Dr. Patrick Chan
Date:
Introduction
A site visit was conducted by two consultants (see photo 1) on 10 September 2005
and soil samples (see Appendix 1) were collected from different spots of the football pitch for
laboratory test accordingly.
Investigation
Adopting the modified protocol and testing tools of the Institute of Groundsmanship Performance Quality Standards for football pitch, the investigation was sub-divided into two aspects: (1) presentational & playing quality and (2) structural quality. The results of the analysis were listed in Appendix 1 & Appendix 2, respectively.
Observations & Summary of Findings
According to the observation of the Consultants, the Bermuda 419 Tifway turf at the football ground of Macau Stadium was maintained in a satisfactory condition. Different items of investigation were listed in Appendix 1 and 2, respectively. In general, the playing surface quality and structural quality were satisfactory. The density and colour (deep green) as well as the root of the turf were above satisfactory level.
Appendix 1
Distribution of Soil Sample & on site pH Reading
Eleven soil samples were collected on 10 September 2005 and physico-chemical analyses were conducted in order to determine the basic soil conditions and suitability for grass growing. All testing were conducted according to international standards.
The pH was neutral to slightly alkaline (6.4 to 7.43), depends on the location of the sampling site and measurement by field equipment or by laboratory analysis. Moisture contents were in the range of 3 to 19%. Stones were virtually not found in the samples and gravel was of less than 10% by weight. All samples were sandy, according to USDA or UK standards. The presence of 2 to 5% of clay and slit contents was important for the microbial growth and retention of moisture and nutrient. The potassium and nitrogen levels in soil were analyzed by the Enviro Labs Limited and ARL Ltd (see below Report of soil analysis).
The potassium level was low and nitrogen level is of typical top soils. Organic content was generally high (2.6 to 6.6%), as ordinary topsoil having a 2% organic content is generally considered good for ordinary plant growth. As the site was relatively young, being formed for just few months, higher organic content as well as potassium and nitrogen in soil and better biotic balance will be achieved in coming years, provided a proper maintenance is continued.
In terms of physico-chemical properties of top soil, no major deficiency is observed. All samples were healthy to support turf growth.
Moisture Content (%)
Organic Matter (%)
Particle Size (%)
c = Clay (%)
s = Silt (%)
sa = Sand (%)
Appendix 2
Assessment on Presentational & Playing Quality
1. Measurement of height of vegetation
a) Equipment used: direct measurement with a measuring tape (see photo 3)
Photo 3
b) Sampling number: A total of 40 samples were measured. For distribution of samples, please refer to the following diagram.
c) Analysis of results:
- The results of individual spot were listed in the above diagram. The height of vegetation (grass) ranged from 2.1 to 3.0 with an average of 2.5 which is within the satisfactory range. (Note: Satisfactory range of the height or vegetation should be >2.0 ≤2.5. )
2. Assessment of evenness
a) Equipment used: An one metre straight edge and measuring tape were used to measure the gap beneath the straight edge (see photo 4 & 5)
Photo 4
Photo 5
b) Sampling number: A total of 40 samples were measured. For distribution of samples,
please refer to the following diagram.
Note: * measurement of the gap underneath the straight edge
# measurement of the gap underneath the gap and thickness of the straight edge
(4 cm thick)
c) Analysis of results:
The results of individual spot were listed in the above diagram.
3. Estimating the percentage ground cover of a range of components
a) Equipment used: A frame size has internal dimensions of 500mm X 500mm and is divided into 100 squares of 50mm X 50mm. (see photo 6)
Photo 6
b) Sampling number: A total of 40 samples were measured. For distribution of samples,
please refer to the following diagram.
C) Analysis of results:
The results of individual spot were listed in the above diagram. The component (individual square) that covered over half a square with weeds and / or bare areas amounted to 10 out of 4,000 unit of individual squares, i.e. 2.5%
(Note: Less than 5% of weeds and / or bare areas are regarded as satisfactory.)
4. Determination of ball bounce
a) Equipment used: A measuring stick and a long ladder were used. (see photo 7)
Photo 7
b) Sampling number & methodology: A total of 6 spots were selected. For distribution,
please refer to the following diagram. The football was released from the test height of 3
metres and the rebound height was measured by careful observation of the consultants.
c) Analysis of results:
The results of the ball bounce test indicated that all six test positions with 5 reading per test position ranged from 40% to 43%, which is regarded as very satisfactory. (Note: Ball bounce >40 ≤45% are regarded as satisfactory.)
5. Determination of ball roll
a) Equipment used: A ramp, a football and measuring tape. (see photo 8 & 9)
Photo 8
Photo 9
b) Sampling number and methodology: A total of 6 spots were selected. For distribution, please refer to the following diagram. The football was released from the top of the ramp (1 metre in height) and the distance rolled was measured. If the football ends up more than 1 m deviated from the centre line of the ramp, that measurement should be disregarded and a further ball roll should take its place.
Remark: →ball rolling direction
c) Analysis of results:
The results of the readings with an average of 3.06 metres distance of ball rolling (i.e. around 3 times of top of the ramp) indicated the smoothness / resistance of the turf is satisfactory. Attention must be made for those spots which have such readings greater than 3.30m (means faster than usual) or smaller than 2.70m (means slower than usual).
Moreover, the majority of these 30 readings (less than 10%) were rolled in a straight line (less than 0.3 metre deviated from the measuring tape. This indicated the roughness of the turf is satisfactory.
6. Measurement of thatch thickness (including root and root zone depth)
Basically, all nine soil samples collected for laboratory test has reported to have an average of 10cm root and root zone depth (see photo 10) which indicated a highly satisfactory level.
Photo 10
Final Remark
It is encouraging to see the major events of the 5th East Asian Games, including the opening ceremony, track & field events and the football semi-finals & final, were held successfully at the Macau Stadium. More important, the turf performance has been maintaining a high standard throughout this period. (Note: Photo 11 & 12 were taken during the 5th East Asian Games; Photo 13 & 14 were taken around one week after the Games.)
References
1. “ Football Performance Quality Standards.” The Institute of Groundsmanship. June 2004, 2nd Edition. (2.1)
2. “ A Summary Report on the Physical Analysis of the Top-soil Samples Taken from the Grass Pitch of the Joint Sports Centre at Renfrew Road, Kowloon Tong, Kowloon.” Joint Sports Centre, Hong Kong, December 2000.
Consultants: Dr. CHAN Ping-cheung, Patrick (Head of Physical Education Section, The Hong Kong Polytechnic University cum Chairman of Joint Sports Centre Operation Sub-Committee)
Dr. CHAN Yuk-sing, Gilbert (Assistant Professor of Applied Biology, The Hong Kong Polytechnic University)
Observer: Mr. LUI Lai-yee (Assistant Manager of Joint Sports Centre)