Environmental Engineering Reference
In-Depth Information
Top-soil
Sand
Gravel
10-cm drain
Strip drain
Fig. 10.4. A traditional pipe drain and a strip drain.
The cynodon on rugby fields is usually maintained under a very
intense fertilization programme. Water-soluble ammonium nitrate, some-
times interchanged with urea, is the primary source of nitrogen. Nitrogen
is applied frequently, at high rates, about 0.5 kg per 100 m
2
per month,
and periodically supplemented with other essential nutrients. Mowing
height is maintained at 20-30 mm, and when the one-third rule is
followed (i.e. no more than one-third of leaf area is removed at each
mowing), mowing frequency usually ranges from 2 to 3 times a week.
Cynodon grown under such a high fertilization programme requires
considerably more irrigation than do moderately maintained areas; its
watering needs are typically higher by 50%. The size, durability and
placement of sprinkler heads must take into account specific conditions
of the rugby game. Sprinkler heads should be as small as possible, placed
exactly at ground level and made from materials that will not be
destroyed by athletes wearing shoes with cleats. The irrigation system
must be designed so as to provide even distribution of water, but at the
same time, sprinklers should not be placed in the areas where traffic is
the heaviest. Like drainage, sports-field irrigation should be designed by
experienced professionals.
During a time when games are not scheduled for at least several
weeks, deep-tine aerification should be performed. Soil compaction, es-
pecially where players line up, is usually too great to be alleviated by
ordinary coring with hollow tines, and sometimes deep-tine aerification
must be performed. After aerification, top-dressing with sand is routinely
recommended. Rugby fields may need periodic dethatching. Because
some thatch on rugby fields is desired, dethatching once or twice a year
is usually sufficient.
Post-emergence herbicides such as MSMA mixed with 2,4D should
be used to control grassy and broad-leaved weeds. Herbicide treatments
should be made during periods when games are not scheduled and also
when no other environmental stresses are expected.
