Willow
(Salix viminalis)
Prepared by: Józef Pyrczak
Types of biomas used to produce
energy.
• Wood and its waste, including energy crops,
• straw and grain,
• agricultural products and waste,
• organic industrial waste , e.g.
brewing industry residues, paper industry
waste.
Types of willow found in Poland
Trees – Goat Willow, White Willow, Crack
Willow, Hoary Willow (Salix eleagnos).
Shrubs – Goat Willow, Common Osier, Almond
Willow, Grey Willow, Eared Willow, Rosemary
Leaf Willow, Purple Willow.
Features of a Common Osier –
select wood willow:
• very rapid biomass growth,
• increased resistance to vermin and diseases
• high energy value of wood.
Salix viminalis energy willow plantation
Part of plantation ready for harvesting
Plantation diversification – improved resistance to vermin and diseases
Site selection and soil preparation
• Most advantageous conditions are provided by 3rd, 4th
and 5th quality class soils
• 5th quality class provides lower yields.
• Dry sandy soils (6th class) are not suitable for growing
energy willow.
• Most advantageous level of groundwater
during the Summer for sandy soils is 100-300 cm ,
and 160 – 190 cm for clay.
• Willow often dies away in cases of long term waterlogging
exceeding 2 weeks
Site preparation
• Grubbing and mowing existing floral cover.
• Ploughing and rotory cultivating.
• Application of a “total” herbicide.
• Adjusting soil pH (pH 5,5 -7) and composition to
requirements.
• Deep ploughing.
Directly prior to planting:
• harrow
• application of soil-applied herbicide (Casoron, Faworyt,
or Lontrel).
4 –row planter to be operated by 4 people
Willow unrooted cuttings for vegetative propagation
Correctly prepared unrooted cuttings
should satisfy following
requirements:
• length 20 – 25 cm and thickness 5 – 12 mm
• have at least 5 “asleep” shoots,
• healthy, clean and of appropriate moisture,
• be kept in water for up to 48 hours prior to
planting.
Planting with 4 –row planter
Planting with 2–row planter
Planting efficiency
• Manual planting by 10 people – 1 ha in 8 – 10
hours of work, providing 25k cuttings
per 1 hectare.
• Mechanical planting depending on the type of
the planting equipment
4 people – 0,8 do 1,2 ha in 1 hour of work,
providing 25k cuttings per 1 hectare.
Newly planted energy willow plantation
Recommended planting design
for small plantations (32k of cuttings/1ha)
Recommended planting design
for big plantations (18k -24k of cuttings/1 ha)
Young shoots from planted willow cuttings
Upkeep of inter-rows
Chemical weed killing
(Recommended pesticides and dosing for willow plantations)
Inputs doses
Willow regrowth
3 years growth schedule:
1st year 25 - 28 %
2nd year 31 - 35 %
3rd year 40 - 41 %
Yield of dry wood:
• harvest every year – 14.81 t/ha per year
• harvest every 2 years – 16.07 t/ha per year
• harvest every 3 years – 21.47 t/ha per year,
On average 17.45 t/ha dry mass per year.
“Class” combine harvester
Direct chip harvesting from willow plantation efficiency up to
1 hectare /hour of work
Storing willow in sheafs
Machinery for two stages biomass harvest
Two stage harvest of biomass from willow plantation
Natural moisture of biomass
• At the end of vegetation period 53-58%.
• In February (Winter) 43-46%.
• In May, June 34-30%.
Dry willow wood chip
Wood chip stored on the field
Pellets from harvested biomass
Basic parameters of willow pellets
(Salix spp.) and sida pallets (Sida
hermaphrodita R.)
Wyszczególnienie
Wierzba
Ślazowiec
Wilgotność (%)
7,5
7,9
Zawartość popiołu (%)
1,38
3,43
Ciepło spalania (kJ/kg)
18708
18247
Wartość opałowa (kJ/kg)
16883
16036
Gęstość nasypowa (kg/m3)
635,6
517,2
Wartość opałowa (GJ/m3)
10,73
8,30
Thank you.