Plant Crops Bioenergy Research UK
Reed Canarygrass
Reed canarygrass (Phalaris arundinacea L.) is a robust coarse perennial rhizomatous grass with a C3 photosynthetic system. It is native to subtropical and temperate zones of the Northern Hemisphere and commonly inhabits damp meadows, river banks and creeks. This species flowers between June and August and grows to between 0.60 and 2.0 m in height. It can be propagated by both seed and vegetatively from rhizomes.
Management characteristics
Reed Canarygrass is very tolerant to wet soil and is best sown in damp to wet but not waterlogged oxygen deficient soil. Although it can also be grown on dry soil it is not tolerant to drought or salt stress. Establishment is from seed (approx 250 kg ha-1) and sowing and harvested can be achieved using conventional machinery. Therefore this crop offers a low level of production costs. Commercially viable production is achieved within two years and only during the establishment year may weed competition be a problem. The production of a well developed rhizome and root system means re-drilling may only be necessary every 8-10 years. This species is well adapted to cool temperate climates and poor wet soils, but can be affected by rusts, mildew and other fungi, however these cause little reduction in productivity.
Harvest and yield
Reed Canarygrass is most commonly harvested once a year with a mower-conditioner and then baled. Studies in Sweden identified a spring (after snow melt) harvest as ideal for energy production. An over wintered standing crop has a lower moisture content at spring harvest, commonly 10 - 15 %, reducing the cost incurred by drying. Macro and micro nutrients are also returned to the roots and soil through the winter this is beneficial to soil nutrient status and reduces the production of undesirable by products during biomass combustion.
Reported yield ranges are from between 3.3-5.2 ODT ha-1 yr-1 in Sweden depending on variety, to 11-19 ODT ha-1 yr-1 in Switzerland depending on site and fertilizer regime, highest yields were obtained with application of 180 kg ha-1 NH4-N liquid manure (Bassam, 1998 and references within). Maximum yields identified from a UK wide trial were 8.7 ODT ha-1 and after four years mean yield was around 5.38 ODT ha-1 yr-1. Maximum yield potential was not realized and nitrogen deficiency was identified as the primary cause, for years two and three of the trial 60 kg N ha-1 were applied (DTI, 2006).
Broad chemical composition and energetics
The broad chemical characteristics of Reed Canarygrass on a percentage basis are: 28% Cellulose, 22% Hemicellulose, 14% Lignin, 8% Ash (of which a high % is silica), 28% Other. This crop has a net calorific value of 16.2 GJ t-1 of dry matter (4.5 MWh t-1 of dry matter). The energy inputs (MJ) and the biomass energy output (MJ) were modeled for reed canarygrass during a 20 year cropping period. This took into account the energy demanding establishment phase, the high yield productivity phase and the final energy demanding decommissioning phase. During this 20 year period the ratio of energy output from the harvested biomass to energy input to attain the biomass was 20.4 (Bullard and Metcalf, 2001).
References
Bassam N. El. 1998. Energy plant species. Their use and impact on environment and development. James and James (Science Publishers) Ltd. London, UK
