Index of Species Information
SPECIES: Pinus sylvestris
SPECIES: Pinus sylvestris
AUTHORSHIP AND CITATION :
Sullivan, Janet. 1993. Pinus sylvestris. In: Fire Effects Information System, [Online].
U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station,
Fire Sciences Laboratory (Producer). Available:
SCS PLANT CODE :
COMMON NAMES :
The currently accepted scientific name of Scots pine is Pinus
sylvestris L. . Scots pine introduced in North America
are nearly all the typical variety, Pinus sylvestris var.
LIFE FORM :
FEDERAL LEGAL STATUS :
No special status
OTHER STATUS :
DISTRIBUTION AND OCCURRENCE
SPECIES: Pinus sylvestris
GENERAL DISTRIBUTION :
Scots pine is the most widely distributed pine in the world. It's
native range includes Scotland, Scandinavia (excluding Denmark),
northern Europe, and northern Asia. It is introduced in many areas in
the United States and Canada, and is naturalized in the Northeast and in
the Great Lakes states [29,32,42].
FRES10 White - red - jack pine
FRES11 Spruce - fir
FRES15 Oak - hickory
FRES18 Maple - beech - birch
FRES19 Aspen - birch
CT DE HI IL IN IA ME MA MI MN
NH NJ NY OH PA RI VT WI NB NF
NS ON PE PQ
BLM PHYSIOGRAPHIC REGIONS :
KUCHLER PLANT ASSOCIATIONS :
SAF COVER TYPES :
SRM (RANGELAND) COVER TYPES :
HABITAT TYPES AND PLANT COMMUNITIES :
In Europe and Asia, Scots pine forms a boreal forest type with Norway
spruce (Picea abies). Scots pine is listed as a dominant species in
the following classification: Forest types and their significance .
SPECIES: Pinus sylvestris
WOOD PRODUCTS VALUE :
Scots pine is used for pulpwood and sawlogs .
IMPORTANCE TO LIVESTOCK AND WILDLIFE :
The pine grosbeak feeds on the terminal and lateral buds of Scots pine.
Porcupines consume the bark, and girdle small trees. White-tailed deer
will browse Scots pine . Moose browse it in Scandinavia and Russia
When compared to other ornamental species, Scots pine is low in
preference for white-tailed deer .
NUTRITIONAL VALUE :
COVER VALUE :
VALUE FOR REHABILITATION OF DISTURBED SITES :
Scots pine is planted for erosion control . It is used to reforest
coal mine spoils. Such plantations are valued chiefly for Christmas
tree production, providing screening and wildlife food and cover, and
aesthetics [5,21,56]. In Europe, it is planted to reforest burned sites
OTHER USES AND VALUES :
Scots pine is a highly preferred Christmas tree, accounting for 30
percent of all trees planted for that purpose . As a Christmas tree
crop, it can be highly profitable in agroforestry systems which combine
the production of row crops with tree plantations . Scots pine is
widely planted as an ornamental, and for windbreaks in the central Great
Scots pine is used to monitor the effect of air pollution on plants .
OTHER MANAGEMENT CONSIDERATIONS :
Scots pine is usually managed with a shelterwood or uniform compartment
system. In the Northeast and the Great Lakes states, reproduction is
abundant on sandy sites .
Scots pine requires high light intensities for good growth, but has
modest nutritional demands . Certain ground vegetation types are
used as site quality indicators for Scots pine in Europe [7,35].
Scots pine performance varies greatly with site and seed source
[12,39,42]. Yields for most species in Scots pine stands in Germany
were improved when shade-tolerant species (Norway spruce and European
beech [Fagus sylvatica]) were grown in the understory. Scots pine
yields, however, were slightly decreased under those conditions .
Scots pine growth rates decreased with decreasing acidity in greenhouse
tests; optimum seedling growth is on acidic soils .
Scots pine has more branches per whorl than red pine (Pinus resinosa)
or eastern white pine (P. strobus), and is thus weaker at the nodes and
subject to wind damage .
Scots pine is intermediate in tolerance to foliar sprays of sodium
Insects and Disease: Damaging insect species on Scots pine include
pine root collar weevil, pine root tip weevil, European pine sawfly, and
others. Scleroderris canker has become a serious problem in Scots pine
plantations in many areas. Other diseases include Lophodermum
needlecast, brown spot needle disease, and western gall rust [42,43].
BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Pinus sylvestris
GENERAL BOTANICAL CHARACTERISTICS :
Scots pine is an exotic, medium-sized, two-needle pine. Height at
maturity usually ranges from 50 to 100 feet (15-30 m) [18,42]. The
crown is open and spreading. Needles range from 1.8 to 3.6 inches
(4.5-9.0 cm) in length . The bark is relatively thin [18,57]. A
taproot is frequently developed on sandy soils, but is not a universal
trait for Scots pine. The depth of the taproot ranges from 4.9 to 9.8
feet (1.5-3.0 m), but most of the roots are horizontal and within 7.8
inches (20 cm) of the soil surface . A population of middle-aged
Scots pine in Finland had numerous root grafts between neighboring
trees in networks of up to ten trees. Water and nutrients are
transferred from one tree to another through the grafts (Yli-Vakkuri in
Scots pine is long-lived; individuals of nearly 1,000 years of age
occur in northern Sweden . Ages of 200 and 400 years are common in
RAUNKIAER LIFE FORM :
REGENERATION PROCESSES :
Scots pine reproduces by seed. Sexual maturity can be reached as early
as 5 to 8 years of age; the usual range is from 10 to 15 years of age.
Scots pine continues to produce viable seed for up to 200 years. Good
seed crops are produced every 3 to 6 years, with light crops in
intervening years. Seed cones require alternating wet and dry weather
to open; seeds can be retained until early spring. Seed dispersal
distances range from 164 to 328 feet (50-100 m) from the parent, though
the maximum distance is greater than 0.6 mile (1 km) . Seed quality,
germination, and establishment decrease with distance from the parent
Scots pine seedling establishment occurs on bare mineral soil. In
England, however, where Scots pine is invading heather (Calluna
vulgaris)-bracken fern (Pteridium aquilinum) heaths, Scots pine
seedlings were found even in dense stands of bracken fern; the limiting
factor on these sites appears to be proximity to seed source, rather
than density of ground vegetation .
Moisture stress, in the form of repeated cycles of wetting and drying,
has a pronounced negative effect on Scots pine seed germination .
Seedlings establish best with adequate moisture and some shade .
Survival is best when seedlings are planted on microsites close to the
tops of hills, and lowest in overly moist depressions .
There is no naturally occurring vegetative reproduction .
SITE CHARACTERISTICS :
Scots pine is found from sea level to 8,000 feet (2,440 m) elevation,
and grows on a wide variety of soils including peat, though growth on
peat usually results in stunted trees . Growth is best on
well-drained soils . Soil pH ranges from 4.0 to 7.0, but growth is
best between 4.5 and 6.0 [42,56].
Where it is naturalized in northern New York, Scots pine is associated
with black cherry (Prunus serotina), red maple (Acer rubrum), sugar
maple (A. saccharum), American beech (Fagus grandifolia), quaking aspen
(Populus tremuloides), and eastern white pine .
SUCCESSIONAL STATUS :
Scots pine is intolerant of shade . High mortality rates occur for
Scots pine growing under canopy. Few trees survive more than 50 years
under suppression; most do not survive even 7 years of shade [44,47].
Scots pine is not very responsive to release from suppression; trees
under 20 years old show a modest response [44,47]. Scots pine stands
are usually even-aged, or are uneven-aged with distinct age classes. In
Scandinavia, 50 to 70 percent of the trees in a stand commonly belong to
one age class, with the rest of the trees in the neighboring age classes
Scots pine usually regenerates in gaps (forming even-aged clumps) or
after stand-replacing disturbances [44,47,50]. In Sweden, most Scots
pine dominated-forests are maintained by fire. In the absence of fire,
Scots pine is usually replaced by Norway spruce (Picea abies). On some
sites, however, uneven-aged Scots pine stands are self maintaining in
the absence of fire. Regeneration peaks on these sites occurred at long
intervals and appear to be more related to favorable climatic conditions
than to any disturbances. The ability of Scots pine to reproduce
without disturbance is attributed to the thin humus and litter layers of
these poor sites .
The percentage of pine pollen increased after disturbances in soil core
samples dated from 1,430 years BP to present, in an area where Scots
pine is usually present .
SEASONAL DEVELOPMENT :
Scots pine pollen cones open from late May to early June. Pollination
occurs in early summer and is followed by fertilization 12 months later.
Seeds mature and cones ripen from September to October. Seed dispersal
occurs from December to March [27,42].
SPECIES: Pinus sylvestris
FIRE ECOLOGY OR ADAPTATIONS :
Scots pine forests in Sweden are rated as fire-prone and appear to
require repeated fire for their maintenance . In general, pine
forests in Europe (particularly Scots pine forests) which were always
fire-prone have become even more flammable with the advent of fire
exclusion and the discontinuance of the practice of litter collection
for use as animal bedding material, fuel, etc. .
In Sweden, Scots pine dominates forests that have burned with a mean
fire interval of 46 years from approximately 1,100 A.D. to the present.
In some areas, the mean fire interval is as short as 30 years, although
the impact of fire has been greatly reduced in the last 100 years with
fire suppression . A fire return interval ranging from 26 to 146
years was calculated for Scots pine/heather forests in eastern Finland
. In the taiga of northern China, the fire cycle for Scots pine
forests was estimated at 130 years .
The number of years between fires decreased in areas where Scots pine
basal area increased in Muddus National Park, Sweden. In this area,
Scots pine often predominates at the lower elevations where fire is
more common and is replaced by Norway spruce at the higher elevations
where fire is less frequent .
FIRE REGIMES :
Find fire regime information for the plant communities in which this
species may occur by entering the species name in the FEIS home page under
"Find Fire Regimes".
POSTFIRE REGENERATION STRATEGY :
Tree without adventitious-bud root crown
Initial-offsite colonizer (off-site, initial community)
SPECIES: Pinus sylvestris
IMMEDIATE FIRE EFFECT ON PLANT :
Young Scots pine trees are easily killed by fire due to their thin bark
and shallow roots. Based on the ability to recover after defoliation,
the fire resistance of 8-year-old Scots pine trees is rated as low
. The heat tolerance of 1-year-old Scots pine seedlings is low
compared to a number of other conifers, including eastern white pine
. Mature trees are better able to withstand fire; old trees in
Muddus National Park, Sweden, have numerous fire scars, showing that
they have survived repeated fires (intensity unreported). However,
severe fire will kill even mature trees .
A 1974 surface and crown wildfire in Scotland killed 74 percent of all
Scots pine burned. All Scots pine less than 2 inches (5 cm) dbh were
killed outright. Trees greater then 15.2 inches (38 cm) in diameter did
not have immediate mortality, however .
Scots pine seeds are moderately resistant to heat damage, and have a
good chance of surviving fire when buried. Seed germination is
good even at depths of up to 4.6 inches (10 cm) .
Scots pine bark is more resistant to heat than that of Norway
spruce, sugar maple, or white ash (Fraxinus americana) .
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
PLANT RESPONSE TO FIRE :
In Sweden, establishment of Scots pine seedlings at high elevations
increased after fire . Total pine pollen increased after fires in
Swedish core samples dated from 1,430 years BP . A survey of a
burned stand of mature Scots pine in northern China showed numerous
seedlings, but no saplings .
Following the 1974 wildfire in Scotland, Scots pine reproduction was
densest on plots with heather. Very few seedlings occurred on sites
where sapling stands had been killed by fire. Regeneration was 2,500
seedlings per hectare at postfire year 6. By postfire year 12, some
seedlings had overtopped the competing vegetation. Postfire mortality
of burned trees was high. By postfire year 6, 45 percent of trees
greater than 2.5 inches dbh was died. Much of the postfire mortality
was attributed to pine shoot beetle (Myelophilus piniperda) attacks on
fire-damaged trees [46,60].
Scots pine may regenerate from seeds released from cones of burned
trees  as well as from seed from off-site parent trees. Twenty-four
years after a wildfire in Sweden, numerous Scots pine seedlings
occurred on burned sites, concentrated around surviving trees and near
the edges of the burned areas .
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
The climatic conditions that are conducive to fire in Scandinavia are
also conducive to the production of large seed crops .
FIRE MANAGEMENT CONSIDERATIONS :
Fires in Sweden have given rise to uneven-aged stands of Scots pine,
particularly in virgin types that have not been disturbed by humans
. Fire exclusion in Europe has resulted in a conversion of
pine-dominated forests (including Scots pine) to hardwoods .
Prescribed burning followed by tilling, followed by natural
reforestation (known as swaling), has been practiced in Europe for many
years. It has been noted that the more frequently a site has been
swaled, the more likely it is that hardwoods will regenerate on the
site. Sites that have been burned and tilled only once often result in
good Scots pine regeneration .
Scots pine does not regenerate on dry sites occupied by Norway spruce
due to excessive humus buildup and shading. Such sites can be made more
conducive to Scots pine regeneration by prescribed burning. The humus
layer is directly reduced by fire. In succeeding years, it continues to
decrease in thickness, probably due to decreased root mass. Prescribed
burning improves many external growth factors needed for Scots pine
establishment, including nutrition, moisture availability, and soil
Prescribed burning has been used in site preparation for the sowing of
Scots pine seeds in Norway and Finland [3,48]. Performance of Scots
pine approximately 10 years after planting was best on burned sites when
compared to performance on sites that were unburned but had slash
removed, or sites that were unburned and retained slash . Rhizina
undulata root rot has been associated with postfire plantations of
Scots pine. As a result, prescribed burning for site preparation has
been discontinued in Finland and Sweden [1,54,55]. It is possible that
the appearance of Rhizina is associated with prescribed fires that are
too low in intensity . However, the rarity of appropriate fire
weather for prescribed burning, and the labor-intensive expense of
prescribed burning have also contributed to the reduction in prescribed
burning in Scandinavia .
SPECIES: Pinus sylvestris
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