Energy crop supplies

Energy crop supplies

Crops for Energy can supply various energy crops including SRC willow cuttings, energy grass seeds including reed canary grass and switchgrass, and tree seedlings for broadleaved coppice and short rotation forestry (SRF). We can also source eucalyptus seedlings for small scale SRF plots. Please contact us for details.

We also supply small volumes of biomass willow cuttings to householders and small holders through our sister site Wondertree.

SRC willow varieties

SRC willows (Salix spp.) should be planted as intimate mixtures of up to 5 diverse varieties. This helps guard the plantation against damaging outbreaks of disease and pests. Some of the highest yielding varieties (e.g. Tora, Tordis and Resolution) have very similar progenies so one should resist planting a mixture of just these varieties. Research at Long Ashton Research Station and the Agri-Food and Biosciences Institute in Northern Ireland suggests that growing varieties in mixtures can increase the overall yield of the plantation.

Like most crops, SRC produces very good yields on good quality arable land but is much less productive on poor sites e.g. marginal land, ex grassland and upland sites. On a good arable site (grade 1-3 land) it should be possible to produce a yield of 10 oven dry tonnes per hectare per year (odt/ha/yr) from the first harvest. Generally the canopy closes more effectively after the first harvest and weed competition is suppressed. This leads to a significant increase in second harvest yields by as much as 20-40%. On a good site it should therefore be possible to theoretically produce 13 odt/ha/yr. However, it is important to take into account uncropped areas (the Energy Crops Scheme allows for up to 20% open ground) as well as losses of dry matter during harvesting, storage and transport. As a result one should reduce the yield estimates below by 20-30%.

You can read a paper about SRC yield trials here and download recent trial data from this link.

Resolution

This variety is a cross between Salix viminalis and Salix schwerinii. The varieties Jorunn, Bjorn and Quest make up the parentage. It has a tall erect habit with long lancet shaped leaves. It is very fast growing and can reach 4 metres in its establishment year. There is some evidence that this variety can tolerate drought conditions better than other varieties. Yield trial performance has ranged from 6.5 odt/ha/yr on ex grassland sites in the Welsh uplands to 14 odt/ha/yr on good quality arable land in the SW. This variety is not affected by rust and has a moderate susceptibility to beetle damage.

Beagle

This variety was produced from a cross between two Salix viminalis varieties. The female parent was the Swedish variety Astrid. It has an erect habit and lancet shaped leaves but more stems than other varieties. Small plot trial yields have ranged from 6.3 odt/ha/yr on ex grassland sites in the Welsh uplands to 11.8odt/ha/yr on good quality arable land in west Wales. This variety shows moderate resistance to rust and moderate susceptibility to beetle damage.

Endeavour

This variety is a cross between the Russian species Salix schwerinii and the Swedish variety Jorr. It is vigorous, upright and has long tapering leaves. It has produced consistently high yields (around 10 odt/ha/yr) at trials in Yorkshire and Wales. This variety shows good resistance to rust and moderate susceptibility to beetle damage.

Terra Nova

This variety is a three way hybrid that combines the European species Salix viminalis and Salix triandra with the Chinese species Salix miyabeana. It has a very different ancestry to many of the other willow varieties available and is a good choice to add diversity to mixed clonal plantations. It is upright and vigorous with glossy green leaves. There is some evidence that this variety can remove cadmium and other heavy metals from contaminated soils. Small plot yield trials suggest that this variety is lower yielding after the first harvest (6-8 odt/ha/yr) but improves markedly in the second rotation. It demonstrates good field resistance to both rust and beetles.

Discovery

This variety is a cross between the variety Bjorn and Salix schwerinii. It has a tall erect habit with few, thick stems and long lancet shaped leaves. This variety has performed well in trials in West Wales and was the second highest yielding variety in a trial 230m above sea level. Small plot trial yields have ranged from 6.4 odt/ha/yr to over 14.5 odt/ha/yr on good quality arable land in Wales. This variety is not affected by rust and has a moderate susceptibility to beetle damage.

Tora

This variety was produced in Sweden and is a cross between the Salix viminalis and the Russian species Salix schwerinii. It has been successfully grown in the UK for over a decade and is tall, erect and very vigorous. Substantial yield data exists for Tora: From 21 small scale trial plots around the UK, Tora has achieved an average first harvest yield of 10 odt/ha/yr. There is less data from second rotations but from the 7 plots harvested, an average of 13.3 odt/ha/yr was achieved. It is a consistent performer achieving high yields in Northern Ireland, Wales, the south west of England and Yorkshire. It shows good resistance to rust and is moderately susceptible to beetles.

Tordis

This is effectively an improved version of Tora with slightly straighter growth and increased yields. It has produced impressive yields on good arable land (over 11 odt/ha/yr from its first rotation) but small trial plots suggest it is much less well adapted to upland sites. It shows good resistance to rust and is moderately susceptible to beetles.