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Reed Canary Grass

Reed Canary Grass Overview

Reed Canary Grass (RCG) is a perennial, 2 meter high grass with a stiff and robust straw. It is naturally distributed throughout Europe and temperate regions of North America and Asia. It is commonly found in wetlands and flooded areas and thrives in humus-rich soils, but can also grow on mineral soils.

The crop grows well in all of Europe, but is more suitable for northern Europe due to competition from other types of energy crops with higher energy yield further south. The roots are very strong and bind through underground rhizomes when cultivation is established properly. This makes the grass grow in large clumps and is green well into fall. The yield is about 4.2MWh per tonne or about 20MWh per hectare, roughly enough to provide a house with heat for one year.

Location of cultivation

The underground rhizomes are approximately 1cm thick and can root as deep as 3 meters. After establishing cultivation, the crop can be expected to remain productive for about 10-15 years. The quality and quantity of the yield is dependent on type of land for cultivation, type of seed, fertilization and harvest procedure.

A few pointers for selection of cultivation location:

  • Larger coherent cultivations are preferable, at least 0.5 hectares
  • From a combustion standpoint, wetland cultivations are preferable due to lower ash content
  • Drainage must work properly
  • In cold climates, shaded areas should be avoided to the extent possible due to late snow melting in spring
  • Storage and turning areas for trucks should be available at the harvest site
  • Closeness to customer is advantageous

Sowing and fertilizing

Cultivation establishment is the most critical stage for retaining a healthy harvest during the life span of the crop. This is preferably done early in spring to allow proper feedstock growth. Common seed varieties include Palaton, Bamse, Chiefton, Vantage, Venture, Barpa 050 and Lara. Best stands are obtained on a well prepared, firm seedbed with about 15 kg of seed per ha, with a depth of 1-2 cm and seed lines separated by 10-15 cm. Rolling before and after sowing is highly recommended to prevent the seed from going too deep and dry out.

RCG seeds germinate relatively slow, making them sensitive during the first year. Weed control with herbicides is therefore needed prior to sowing. On wetland, Ph can be below 5, and may need liming to increase productivity.

Fertilization procedures for RCG are quite similar to other types of energy crops, and vary depending on soil fertility. The amount of fertilizer can be reduced with spring harvest as the nutrients returns to the roots during the winter. Fertilization should be done early in spring after harvest, but before new sprouts risk getting damaged.

Harvesting

RCG can be harvested with conventional grass harvesting machinery, but local demand determines specific type of harvest method. The first harvest is done two years after sowing, and will be about 20% lower than following years.

After that, the yield will be anywhere from 3 to 7 tons/ha or about 12-30 MWh/ha, depending on soil fertility and fertilization etc. The grass is usually cut down in the fall, and harvested in the spring, and there are several advantages and disadvantages with this approach.

Advantages with spring harvest:

  • The crop dries quickly in spring
  • The whole growing season is utilized
  • More straw in the harvest
  • Lower levels of nutrients, giving better combustion properties
  • Less nutrients removed from the soil

Disadvantages:

  • Hard to cut down the grass if bent down by snow
  • Biomass losses and increased risk for fire due to dryness of the crop
  • Risk for mechanical damage from harvesting machinery if harvest is done early
  • Risk of cutting down new sprouts if harvest is done late, damaging the crop and leading to poorer combustion properties.

Storage, processing and transportation

Storage should be avoided if possible to cut costs. If storage is required, the harvest should be kept in a warehouse. Bales can be stored outdoors under coverage. In those cases, it is important to place the bales on pallets and cover all sides to avoid increased moisture content. The side coverage needs to be attached properly, not only to keep it from blowing away, but also to prevent anyone from getting in under the cover. A situation like that can be lethal because of suffocating gases.

Transportation costs depend on distance and what form the harvest is delivered in, chopped, bales, briquettes or pellets. As the level of density drops, so does the transport distance with retained profit. High density and closeness to customer is therefore desired.