HYBRID ASPEN IN FINLAND - Nordic Forest Research SNSnordicforestresearch.org/.../8/...aspen-in-Finland.pdf · • Hybrid aspen seedlings planted in spring 1988 on a 17 ha agricultural

© Natural Resources Institute Finland © Natural Resources Institute Finland

HYBRID ASPEN

IN FINLAND

Egbert Beuker

Anneli Viherä-Aarnio

Jari Hynynen

Jyrki Hytönen

© Natural Resources Institute Finland

Hybrid aspen in Finland

• Hybrid aspen (Populus tremula x P. tremuloides) was crossed in Finland

in 1950.

• It is considered to be the fastest growing tree species in Finland on

fertile soils yielding about 300 m3 in 25 years.

• The area of hybrid aspen was most extensive at end of 70’s.

• Match industry closed down, vole and moose damages > interest

declined.

2 16.5.2017

• In mid 1990’s new plantations

for pulpwood using short

rotation principles. Area of

plantations reached 1 500 ha,

but demand for aspen for

pulpwood decreased.

• Could aspen be grown for

biomass energy?


Hybrid aspen cultivation in Finland

3 16.5.2017

1997-2003 planted area:

- about 1500 ha.

2005 planned

- 500 ha.

Planned: up to 1000 ha per

year

Both on abandoned fields and

on forest sites

© Natural Resources Institute Finland 4 16.5.2017

Hybrid aspen breeding in Finland: plus tree

selection

Superior tree selection and

wood quality (fibre) analysis

Over 1000 trees selected


• Vegetative propagation of individuals

(micropropagation, strong selection)

• Establishment of clonal trials

• Establishment of growth and yield trials

Hybrid aspen breeding in Finland: clone testing


Hybrid aspen breeding in Finland: clone testing

- 27 clones (2 native)

- 13 trials

- 3x3m spacing

- established 1998


Hybrid aspen breeding in Finland: controled

crossings


Growth and yield trials: different sites

Three sites:

• Trial 1, Lohjansaari (1997)

• Trial 2, Lapinjärvi (1999)

• Trial 3, Lohja (1998)

8 16.5.2017


Growth and yield trials: different clones

Three hybrid aspen clones:

• A = E10476 (in trial 1)

• B = E10467 (in trial 1)

• C = E10490 (in trials 2 and 3)

9 16.5.2017


Growth and yield trials: different spacing

Four spacing distances

• 2,5 x 2,5 m (~1600 trees/ha)

• 3,0 x 3,0 m (~1200 trees/ha)

• 3,5 x 3,5 m (~800 trees/ha)

• 5,0 x 5,0 m (~400 trees/ha)

10 16.5.2017


Annual height growth, m. (dominant height)

11 16.5.2017

Trees/ha


Annual diameter growth, cm

12 16.5.2017


Annual volume growth (m3/ha)

13 16.5.2017


Clone trials: volume per tree after 12 growing

seasons, dm3

14 16.5.2017


Short-rotation coppice for energy: mother stand

15 16.5.2017 Teppo Tutkija

• Hybrid aspen seedlings planted in spring 1988 on a 17 ha agricultural soil at

Vilppula, southern Finland. Vole protection with tubes, vegetation control by

trampling, stand cleaning in 2003 (other tree species removed). The stand (900

trees/ha) was measured in 2012 and was clear-cut in winter 2013 at age of 26.

© Natural Resources Institute Finland 16 16.5.2017 Teppo Tutkija


Experiment: Treatments

BIOMASS PRODUCTION

1. Unfertilized.

2. Nitrogen fertilization (N 100

kg/ha)

PULP WOOD PRODUCTION

3. Thinning of sprouts at age 5-8

4. Thinning of sprouts at age 5-8 +

Nitrogen fertilization (100 kg

N/ha)

N 100kg/ha 2014 (May) and 2015

(May)

17 16.5.2017

12 sample plots (25 m x 25 m),

randomized blocks, four

treatments.

First fertilization when sprouts

were 1-year-old


Stand density

• 99% of aspen sprouts were root suckers

• Fertilization did not affect stand density


Mean and dominant height

Fertilization increased mean height

by 23 cm

Mean height, m Dominant height, m

© Natural Resources Institute Finland 20

Biomass production (leafless above-ground)

• N fertilization increased

significantly biomass (3

t/ha at age 2; 5 t/ha at

age 3)

• 1-year old stand 5 t/ha,

fertilized 2-year old

stand 20 t/ha, 3-years

old stand 29 t/ha

• Share of wood out of

biomass increased from

60% at age 1 to 73% at

age 3


Energy production in three years

Effective heating value

1a 18.841 MJ/kg

2a 18.713 MJ/kg

Wood = 18.637 MJ/kg

Bark = 18.864 MJ/kg

Moisture content 40%

Heating of a domestic house

in Finland 20 MWh/a.

With 3-year old aspen

• 0-fertilization = 4.6 houses

• N-fertilization = 5.6

houses


Conclusions

• Sprouting excellent, lots of

root suckers

• High biomass production,

MAI after 3 years: 8 – 10

t/ha/a

• Nitrogen fertilization

increased biomass by 5 t/ha

in 3 years.

• Hybrid aspen demanding

species

• Mammal damages (moose)

small

• Hybrid aspen promising

species for SRF


Propagation and plant production

23 16.5.2017


Pathogens

Venturia tremulae

Neofabreae populi

Hypoxylon mammatum


Herbivores

• Moose

• Hare

• Vole


Frost damage


Management young plantations, weed control


Thank you!

16.5.2017 28

Documents

HYBRID ASPEN IN FINLAND - Nordic Forest Research SNSnordicforestresearch.org/.../8/...aspen-in-Finland.pdf · • Hybrid aspen seedlings planted in spring 1988 on a 17 ha agricultural