Nordgen seminar, Hämeenlinna, Finland

September 5 – 6, 2012

Seppo Ruotsalainen

Forest Research Institute,

Punkaharju, Finland

Seed orchard seed in direct seeding

of Scots pine – the benefits

0

20

40

60

80

100

120

1980 1985 1990 1995 2000 2005 2010

Are

a, 1

00

0 h

a

Forest regeneration of Scots pine by planting and seeding during the last

30 years

Seeding

Planting

Facts about direct seeding of

Scots pine in Finland

0

20

40

60

80

100

120

1980 1985 1990 1995 2000 2005 2010

Are

a, 1

00

0 h

a

Forest regeneration of Scots pine by planting and seeding during the last

30 years

Seeding

Planting

Facts about direct seeding of

Scots pine in Finland

0

5

10

15

20

25

30

35

40

2003 2004 2005 2006

%

The proportion of seed orchard seed in direct seeding

As compared to stand

seed:

• Heavier (>10 %)

• Better germination

• More expensive (5 –

15 %)

Seed orchard seed Facts and fiction

Statistics: Close to 200 000 ha regenerated by sowing

orchard seed

= 8 % of all Scots pine sowings

= 23 % of all Scots pine cultivations with orchard seed

Currently about 1/3 all sowings with orchard seed

Aim 50 % in southern and central Finland

Studies on sowing of orchard seed

Swedish studies (Wennström 2001 et al.):

- 10% higher plant establishment

- Lower mortality

- Better height growth

Studies on sowing of orchard seed

A Finnish project

Started in 2002

Aim was to compare orchard and stand seed in

direct seeding:

- Germination

- Plant establishment

- Growth

Target area southern and central Finland

Experiments in field conditions corresponding normal

forest regeneration practices

Orchard and stand seed was sown in

comparable conditions

- 4 stand seed lots

- 5 seed orchard seed lots (southern origin)

- 2 (3) seed orchard seed lots (northern

origin)

- 1 control (not sown)

16 seeds/spot, 30 replications (blocks)

Sowing was done on small indentations,

seeds covered lightly with soil

Comparison of seed types in field experiments

Experiments repeated in three years (2002-2004)

Four test sites (in first year only 2)

Number of seedlings counted

- in first summer several times, later once a year

The height of the tallest seedling/spot measured at the end of each growing season

Monitoring continued to the end of 7th growing season

Experimental design & measurements

Punkaharju 2004

Map of one experiment

Locations of the experiments

and seed sources

Koe

Metsikkö

Sv – eteläinen

Sv – pohjoinen

Material in the experiments

Stands

1 98

2 89

3 67

4 78

Seed orchards

5 91

6 98

7 93

8 96

9 96

10 97

11 92

13 97

Representative entries

Nonrepresentative entries

84

Sv249, Pertunmaa 990-1120 2003 5,5 86

Sv323, Mäntyharju

79

Sv320, Joutseno 1020-1170 2001 6,1 66

Sv190, Virrat 960-1100 2001

1080-1280 2001

5,4

6,5

6,6 68

Sv123, Hartola 1100-1300 2001

Sv256, Hartola 1020-1220 2001

5,8 84

6,1 86

Sv124, Iitti 1080-1280 2001 6,1 98

Sv17, Hausjärvi

Kerimäki 1200 1996

1130-1330 1998

4 67

SKA 8.3 1250 2000 5 65

SKA 5.3, Vilppula, Ruovesi 1160 1998 4,7 86

SKA 12.5, Kivijärvi 1020 1999 4,8 95

Preparations for sowing

Sowing work

Punkaharju

Experimental sites

Parkano

Germinated seeds in the autumn, sowing

in 2003

Southern seed orchards best (8 %-unit),

northern SOs equal to stands

Stand

SO - south

SO - North

0

10

20

30

40

50

60

So

lbö

le

Pu

nk

ah

arj

u

Pa

rka

no

Ka

nn

us

Plants, % of seeds

Sowing spots with 4 or more seedlings

Average for whole material

Growing season 1 3 2

Stands

Seed

orchards

Sowing spots with 4 or more seedlings

Comparison of orchard and stand seed

40

60

80

100

1st_year 2nd_year 3rd_year

%

Year

Stand

Seed orchard

-20

-10

0

10

20

1st_year 2nd_year 3rd_year

Dif

feren

ce S

O-S

tan

d

Year

KANNUS 2003

KANNUS 2004

PARKANO 2002

PARKANO 2003

PARKANO 2004

PUNKAHARJU 2002

PUNKAHARJU 2003

PUNKAHARJU 2004

SOLBÖLE 2003

SOLBÖLE 2004

Height of the tallest seedling in spot

Average for whole material

Growing season 1 3 2

Stands

Seed

orchards

He

igh

t, m

m

Height development, tallest seedling in spot

Comparison of seed orchards and stands

0

30

60

90

120

150

180

1st_year 2nd_year 3rd_year

Heig

ht,

mm

Year

Absolute values

Stand

Seed orchard

-20

0

20

40

60

1st_year 2nd_year 3rd_year

Dif

fere

nce S

O -

Sta

nd

, %

Year

Relative difference, %

Average

-20

0

20

40

60

1st_year 2nd_year 3rd_year

Dif

fere

nce S

O -

Sta

nd

, %

Year

Relative Differences %

Individual experiments

KANNUS 2003

KANNUS 2004

PARKANO 2002

PARKANO 2003

PARKANO 2004

PUNKAHARJU 2002

PUNKAHARJU 2003

PUNKAHARJU 2004

SOLBÖLE 2003

SOLBÖLE 2004

Delayed germination in Punkaharju,

sowing in 2003

10.9.2012 20

0

2

4

6

8

10

12

14

16

18

-50 0 50 100 150 200 250 300 350

Dela

yed

germ

inati

on

, %

Transfer, dd

SO-south

SO-north

Stand-repr.

Stand-nonrepr.

r=0,930***

Dependence of delayed germination on the difference in

temperature sum between seed ripening site and site of origin

• Delayed germination most frequent in Punkaharju, in

maximum in 2003 sowing (6.6%)

• Connected to seed weight (+) and transfer of origin (+)

Decrease in number of spots with at least

4 seedlings from 2nd to 3rd autumn

10.9.2012 21

0

1

2

3

4

5

6

7

8

9

10

14 16 18 20 22

Ch

an

ge,

%-u

nit

s

Height in 1st autumn, mm

Stand-repr.

Stand-nonrepr.

SO-south

SO-north

r=-0.752** Does this reflect

resistance to frost

heaving?

Mortality due to frost heaving?

10.9.2012 22

-20

-10

0

10

20

1st_year 2nd_year 3rd_year

Dif

feren

ce S

O-S

tan

d

Year

KANNUS 2003

KANNUS 2004

PARKANO 2002

PARKANO 2003

PARKANO 2004

PUNKAHARJU 2002

PUNKAHARJU 2003

PUNKAHARJU 2004

SOLBÖLE 2003

SOLBÖLE 2004

Fine soil, late

snow cover

Extremely late

snow cover

(mid-January)

Conclusions

•Plant establishment equal

with orchard and stand seed

•Seed orchard material has

lower mortality in frost

heaving prone conditions?

•Seed orchard material has

clearly better (20%) height

growth