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The
layout of a vineyard
The
single-trellis, pitched-roof structure:
providing hail protection for table grapes:
This
type of structure has long been used successfully by table grape growers
in the Northern Transvaal (South Africa) and is designed to ensure effective
shedding of hail which falls on the tractor paths between rows of vines.
At the same time, the design provides for the longer uprights and trellis
poles to form an integral part of the trellis system. The sides can be
closed with max. 55% construction shadecloth to minimize wind damage and
to keep birds and insects out to a large extent.
A
great deal of time, money and effort can be saved if hail protection structures
are planned at the same time as it is decided to plant the vineyard.
The layout of the
vineyard:
The
following are some general recommendations:
- Blocks
should be limited to a maximum of 328.08 x 328.08 ft (100m x 100m).
It is very difficult to work with netting on rows longer than 328.08
ft (100m) and the commonly used materials are not made to withstand
the heavier load.
- Remember
to provide sufficient space for anchors and tractor turning circles.
- In
general, plant rows are 9.84 ft (3m) apart, with a spacing of 4.92-6.56
ft (1.5m - 2m) in the row and the upright poles spaced at 32.80 ft (10m)
in the row.
  
Planting of poles:
- Poles
should extend at least 9.84 ft (3m) above the ground level and be planted
and well compacted at a depth of 23.62 inches (600mm).
- Anchored
perimeter poles should be at least 4.92-5.90 inches (125-150mm) diameter,
with the same diameter trellis pole. Upright poles in the rows - which
mainly support vertical loads - need only be 3.93-4.92 inches (100-125mm)
and trellis poles 2.95-3.93 inches (75-100mm).
- A
straight row of vines is obtained by tensioning the first trellis wire,
or the wire carrying the micro-irrigation pipe. Plant holes can be moved
slightly if they coincide with the poles. Straight rows of poles ensure
a stable, neat structure.
Points to remember when planning or erecting hailnetting:
- The
ideal time to erect hail netting is during winter when the crop has
been picked and the vines pruned.
- Only
the apex wires should be tensioned, before putting up the netting, to
stabilize the pitch. The edge wires, forming the gutter, can only be
tensioned once the netting is in place since they are laced into the
netting.
Other
building projects:
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