Short rotation plantations
Being particularly fast growing trees, the cultivation of poplars and willows on agricultural land enables a cost-efficient and high-volume wood production within a few years . The selection of varieties, planting layouts and harvest cycles are primarily depended on the intended wood utilisation as well as the soil conditions.
The following recommendations for short rotation coppice (SRC) plantations and wood plantations with medium to long term rotations (harvest intervals) classified as short rotation forestry (SRF) offer some inital guidlines for planning individual fast growing tree planations.
For more information on fast growing tree plantations and different planting technology solutions, please visit our Lignovis webseite here.
Cultivation of Short Rotation Coppice (SRC) plantations
To establish short rotation coppice (SRC) plantations, poplars or willows are planted in rows with high densities of more than 10,000 units per hectare. These cropping systems are usually harvested every 2 to 5 years with modified field chippers or special accessory chipping machinery during the wintertime. Due to the established root system the trees swiftly regrow from the stumps and show significantly higher yields in the subsequent growing seasons.
For planting, a deep subsoiling and a homogeneous seed bed preparation is essential. The key to a successful short rotation plantation establishment is to keep the area free from any weed competition in the first months. By ensuring a good weed control, tree heights of up to 4 meters are possible in the first 6 months. However, when trees face heavy weed competition, they often reach only 50-100 cm in height. Also, poor development in the first year results in relatively slowl growth in the following years, compared to plantations which have been managed well from the beginning.
Short rotation plantations hold the potential to quickly produce large volumes of biomass for marketing or other purposes. Due to the high degree of mechanization during harvesting, larger and more homogeneous fields are particularly suitable for this type of cultivation.
Usually, wood chips volumes which are harvested by field chippers are directly burnt in large heat (& power) plants without preconditioning. Otherwise, the chips are technically dried to achieve storage stability and a high quality with low water content for small wood boilers or gasification systems.
You could download a detailed guide how to grow SRC plantations here…
Poplar plantation in medium to long rotations (SRF)
Poplars are particularly suitable for establishing fast growing plantations with longer rotation periods also called "Short Rotation Forestry" (SRF). For those plantation systems with growth periods of 6 to 20 years we are normally recommending the following planting densities:
Medium rotation: 2,000 to 4,000 trees / ha (harvest every 6 to 8 years)
Long rotation: 1,000 to 2,000 trees / ha (harvest after 9 to 20 years, including thinning)
For establishing plantations with medium rotation time, poplar rods or cuttings with 30 cm should be used. For long rotation poplar rods planted.
Poplars in medium and long rotation reach stem diameters that exceed the capacity of field chippers. Hence, forestry machinery or manual chain-saws are usually applied for harvesting. These harvest techniques could be easily combined with the natural drying process of stems stored on the field’s side without significant losses of dry matter or quality. In addition, headlands can be minimized as no space for the turnaround of field chippers is needed.
Thus, the medium and long term rotation is of particular interest for wood consumer that require larger diameter or dry wood chips. Also the production of logs or so-called industrial wood for the wood-based industry is possible in longer rotation regimes.
Due to the longer growth periods, combined with larger wood quantities on stock, the establishment of SRF (short rotation forestry) plantations qualify especially for smaller areas or sites with limited accessibility during wintertime. Poplars which are cultivated in medium rotations are also re-sprouting from the stumps after harvest.
