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Reed canary grass (RCG) is a rhizomatous perennial C3 plant found in wet conditions of the sub-tropical and temperate regions of the northern hemisphere. It forms an extensive root and rhizome system with above ground upright stiff stems reaching a height of between 0.5 and 2m. The bulk of the biomass from RCG is incorporated into the lower leaf blades and it flowers between June and July. Agronomy The small seeds (1x4mm) are broadcast (2.5kg / acre) and harrowed in
spring into a well prepared damp seed bed that is prepared to a fine
tilth, with an even surface, appropriate weed control and adequate
nutrient balance. The plant is shallow rooting and therefore cannot
withstand prolonged drought or saline conditions. Broadcasting onto
a dry tilth will result in poor establishment. It requires a regular
flow of oxygen rich water across its roots and therefore does not benefit
from wet stagnant anaerobic conditions. As a plant native to temperate
zones it displays good frost tolerance.
The crop can establish commercially productive levels within 2 years and has a productive life of between 5 and 7 years, after which productivity declines and the crop requires re-sowing. RGC is typically harvested annually. The crop will go to seed in mid summer and then begin to dry out. If not harvested until late winter the crop can achieve low moisture content (10-15%). Reed canary grass can be suitable for multiple harvests in one year (1-4). If harvested when still green a larger addition of fertiliser may be required to sustain production levels. However, where herbage quality is not the goal, more biomass may yield from lower harvest rates for equivalent fertiliser applications (Lechtenberg et al., 1991). Harvest regime In Wales and England is currently regarded to reach optimal production at 1-2 cuts per year. The crop is harvested using a mower conditioner and baled to required sizes. NH4-NLiquid manure has been used at a rate of 80 – 180kg/ha (Mediavilla et al., 1995) and yields reported range between approx, 3 - 5 t dry matter / year in Sweden (Olsson, 1993), to 11 – 19 t dm /year in Switzerland (Mediavilla et al., 1995). In the UK yields of 16 t dm /year have been reported. The net heating heat value of the crop is slightly higher from a summer harvest than if harvest is delayed until the end of winter at 17.9 and 17.6 MJ/kg, respectively (Olsson, 1994). Weed competition in the establishment year can be a major concern for
this crop. RCG can often appear to initially establish poorly and be
under threat from weed competition. However, if sown correctly under
damp conditions, RCG will completely dominate coverage by the second
growing season. Pests and diseases such as mildew, rusts and fungus,
cause little reduction to production.
In comparison to other wood and non-wood biomass crops, RCG has a short commercially viable life-span before re-sowing is necessary. As a consequence soil disturbance is required more frequently. However, yields can be comparable with other crops, it is much cheaper to sow than the other grass crops, susceptibility to frost is low, giving a greater security of consistent yield and there is no requirement for specialised machinery. Low moisture content and short fibre length make it ideal for fuel pellets
and briquette production and also for fine quality paper. It is used
for animal fodder and bedding, and as a bio-filter for wastewater treatment. Mediavilla, v., Lehmann, J., Meister, E., Stünzi, H. & Serafin, F. (1995) Energiegras/Feldholz – Energiegras, Jahresbericht, 1995, Bundesamt für Energiewirtschaft, Bern. Olsson R. (1993) Production methods and costs for reed canary grass as an energy crop. In: Bioenergy Research Programme, Publication 2, Bioenergy 93 Conference, Finland. Olsson R. (1994) A new concept for reed canary grass production and its combined processing to energy and pulp. In: Non-wood Fibres for Industry, Pira int./Silsoe Research Institute Joint Conference, Bedfordshire, UK. |
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