Agriculture Reference
In-Depth Information
Fig. 20.7.
The hemp stock market in Odžaci at the beginning of the 20th century.
The vegetative period of hemp is relatively
short and this allows the effects of summer
droughts to be avoided, or minimized; an
important consideration for crops grown on
the Pannonian plain. This also explains why
hemp yields over time are more reliable and
less variable than those obtained for maize and
other cereal crops.
The technology required for hemp cultiva-
tion is relatively simple and, except for harvest-
ing, does not require any special equipment.
With regard to plant protection, hemp
can be described as a true ecological plant, for
it does not require intensive application of
pesticides. In Serbia, there have been no dis-
eases or insects causing notable economic
losses on a regular basis (C
ˇ
amprag
et al
.,
1996). Hemp's reaction to weeds can legiti-
mately be compared to that of a weed, for it is
able to smother and destroy them, particularly
when sown at high density (Starˇevi´, 1978),
although the same phenomenon can also be
seen at lower sowing densities. In recent
years, Johnsongrass (
Sorghum halepense
)
has become the most serious weed reported
in the Vojvodina Province, and the cultivation
of industrial hemp is seen as an effective eco-
logical means of controlling and eradicating
this weed.
Over the past few years, the parasitic
weed,
Orobranche
, which taps into the roots
of its hosts to feed, has been reported on hemp
plants in a number of areas. While the robust
hemp plants do not appear visibly to be affected
by these attacks, this phenomenon needs to be
monitored for this parasite has become a sig-
nificant menace to sunflower production.
Experiments aimed at determining the racial
structure of
Orobanche
sp. originating from
hemp plots as opposed to that from sunflower
plots are under way.
The naturally growing 'weedy hemp' or
'wild hemp' occurs seemingly spontaneously
across the country, even in areas where hemp
has never been grown (Vrbniˇanin
et al
.,
2008). Roadsides, ditch banks and various
undisturbed areas are the most frequent places
for hemp occurrence (Fig. 20.8).
Industrial hemp production for fibre is
organized by companies who contract out to
farmers, large and small, with farms of 50-100
ha to only 1-2 ha.
Where hemp is grown for fibre, a sowing
density of 75 kg/ha is practised, with rows
spaced 12.5 cm apart.
In the production of fibre hemp, a tractor-
powered mower followed by hand binding, or
the Russian-made mower-binder 'Žatka', are
used. The sheaves are stacked into 'fishbone'
or round stacks for drying in the field. Bundles
or bales pressed from them are transported to
hemp-processing facilities. This production
technology is rather labour-intensive and its
modernization is required.
