Journal of Vegetation
Journal
Science 8: 437-446,1997
437-446, 1997
VegetationScience
? IAVS;
©
IAVS; Opulus
Printed in
in Sweden
Sweden
OpulusPress Uppsala.
Uppsala. Printed
437
Temporal
changes in height
height and diameter growth
Temporal changes
growth
for two Nothofagus
N othofagus species
species in New Zealand
Runkle, James R.1,
R.I, Stewart, Glenn H.2
R.3
H.2 &
& McClenahen, James R.3
1
Department ofBiological
Dayton, OH 45435,
of Biological Sciences,
Sciences, Wright
45435, USA;
'Department
Wright State University,
University, Dayton,
E-mail [email protected];
[email protected]; 2Department
2Department ofPlant
Science,
Lincoln
University,
Fax +1 937775
937 775 3320; E-mail
Plant
Lincoln
Science,
of
University, P.O.Box 84,
Lincoln,
Canterbury,
Zealand;
3Silvancare,
P.O.Box
272,
Shreve,
OH
44676,
New
USA
Lincoln, Canterbury,
Zealand;
272,
44676, USA
Abstract. We examined
whether the
the growth
examinedwhether
two
growthdynamics
dynamicsof two
species
can explain
their coexistence.
particular, we examexamIn particular,
coexistence. In
species can
explain their
ined New Zealand
forests dominated
dominated by
Nothofagusfusca and
ined
Zealandforests
and
by Nothofagusfusca
N. menziesii
determine whether
whether both
both species
to determine
N.
menziesii to
can reach
reachthe
the
species can
in
canopy
in
tree-fall
gaps.
Stems
in
a
gap
and
other
stems
(in
tree-fall
Stems
and
other
stems
(in
canopy
gaps.
gap
together) were
were destructively
pairs: one
one of each
each species,
pairs:
species, close together)
destructively
sampled
theirbases
and aged
at their
bases and
and at
at heights
1.4 m and
and 3
sampledand
aged at
heights of 1.4
intervals thereafter
as
possible.
m,
m intervals
and at
at 2 m
thereafteras
as high
as
For
m, and
high possible. For
additional
pairs of adjacent,
additionalpairs
sized stems,
one of each
each
stems, one
adjacent,similarly
similarlysized
to envispecies,
were analyzed
for responsiveness
widthswere
envianalyzedfor
species, ring
ring widths
responsivenessto
In general
ronmental
faster growth
ronmentalchanges.
the faster
rates of N.
N.
changes. In
general the
growth rates
fusca were
were sufficient
balance the
N.
to balance
sufficient to
the greater
abundanceof N.
fusca
greaterabundance
in the
were able
menziesii
menziesiiin
the understory,
such that
thatboth
bothspecies
able to
to
understory,such
species were
both species
reach
canopy. Stems
reachthe
the canopy.
Stems of both
at similar
similarrates
rates
species grew
grew at
for decades.
were able
periods of
for
decades.Both
Both species
ableto tolerate
some periods
toleratesome
species were
to respond
due to
suppression
(climatic or
andto
to opportunities
or due
to
respondto
opportunities(climatic
suppressionand
mild
mild disturbances).
disturbances).
Keywords:
Disturbance;Forest;
Forest;Height
Keywords: Competition;
Competition;Disturbance;
Heightgrowth;
growth;
Tree-fall
Tree-fallgap;
Tree-ring.
gap; Tree-ring.
Nomenclature: Allan
Allan (1961).
Nomenclature:
(1961).
Introduction
For two species
coexist, their life history
species to coexist,
history atto
grow,
survive,
reproduce)
tributes (abilities
(abilities
grow,
reproduce) must be
balanced within their shared environment such that both
species
of the time but
species can dominate some areas some of
neither can dominate all areas all of
of the time. A dynamic
dynamic
coexistence
primacoexistence can be maintained if
if species
species differ primarily
in
their
abilities
to
regenerate
following
abilities
rily
regenerate following disturbance. Such species
differences
can be important
even
differences
species
important even
for disturbance regimes
regimes dominated by
small
gaps,
by
gaps, each
formed by
by the death of
of one or a few individuals.
individuals. Light,
Light,
soil moisture, and other properties
properties vary
between gaps
of
vary between
gaps of
different sizes
of
the
same
size
(see
sizes and within gaps
of
(see
gaps
Veblen 1992 and review
Veblen
review in Runkle et al. 1995).
1995). The
ability
by specializing
parts of
of species
coexist by
of
ability of
species to coexist
specializing on parts
(between
and
gaps)
has
these gradients
within
been
gradients (between
gaps)
termed''gap
gap partitioning'
partitioning' (Denslow
termed
(Denslow 1980).
1980).
present study
between
The present
examines differences
differences between
study examines
two tree species,
Nothofagus
fusca
(red
beech)
species, Nothofagus fusca (red beech) and N.
menziesii
beech), which
menziesii (silver
which together
(silver beech),
together dominate large
large
areas
New Zealand. Compared
areas offorest
of forest in New
Compared to N. menziesii,
N.fusca
by growth
N.
tolerant (measured both by
fusca is less shade tolerant
growth
and survival),
grows
faster
in
the
open,
stronger
has
survival), grows
stronger
open,
apical
apical dominance, grows
grows larger
larger (typically
(typically to 200 cm
diameter and 30 m tall vs. 150 cm diameter and 25 m tall
for
N. menziesii),
forN.
menziesii), has shorter-lived leaves (1
(1 yrvs.
yr vs. 3-5 yr),
yr),
has a size distribution with relatively
more
large
relatively
large stems,
and is more likely
likely to occur as even-aged
even-aged stands (Wardle
1984). Because
proof these differences,
Because of
differences, it has been proposed
that
fusca
dominates
following
major
disturN.
fusca
following major
posed
bances whereas N. menziesii
menziesii dominates in small gaps
gaps
(Wardle
However, both species
1988). However,
(Wardle 1984; Ogden
Ogden 1988).
species
persist
even when disturbances have
persist in some areas even
produced
only
small
gaps
produced only
gaps for the last several centuries .
lower juvenile
juvenile mortality
fusca
N. menziesii
menziesii has lower
mortality but N. fusca
has faster
growth
rates
and
greater
faster height
height growth
greater adult
survivorship
(Stewart
&
Rose
1990).
When
gaps
are
Rose
1990).
survivorship (Stewart
gaps are
formed, N. menziesii
menziesii has an advantage
over
N.
fusca
fusca
advantage
of its taller height
because of
because
height in the understory.
understory. Whether N.
fusca can reach the canopy
of
fusca
canopy depends
depends on whether some of
its many
short
seedlings
can
increase
in
height
rapidly
many
seedlings
height rapidly
enough
menziesii Stewart et al.
enough to overtop
overtop the taller N. menziesii
1991).
1991). Growth rates for the two species
species vary
vary with gap
gap
size, stem size, and position
gaps
within
(Runkle et al.
position
gaps (Runkle
1995).
fusca grows
1995). N. fusca
grows better under constant, favorable
conditions,
such
as at the center of
gaps, where soil
of gaps,
conditions,
moisture and diffuse
diffuse radiation are at their maximum. N.
menziesii
menziesii grows
grows better near the south edge
edge of gaps,
gaps,
where sunlight
is
more
intense
probably
but
sunlight
probably more varied
during
by other stems. Growth
during the day
day due to shading
shading by
rates for N. menziesii
menziesii vary
more
with location
location than for N.
vary
fusca
(Runkle
et
al.
1995).
1995).
fusca (Runkle
Although
Nothofagus species
New Zealand
Although many
many Nothofagus
species in New
hybridize,
menziesii
is
in
different
section
of
N.
menziesii
a
section
of the
hybridize,
genus
than
fusca
and
the
do
not
hybridize
two
N.
fusca
hybridize
genus
(Philipson
1991).
(Philipson & Philipson
Philipson 1988; Hill & Read 1991).
We attempted
concerning
attempted to answer two questions
questions concerning
coexistence.
coexistence. First, are
are the initial (following
(following disturbance)
438
Runkle,
al.
J.R. et al.
Runkle,I.R.
height
density advantages
and density
menziesii in the
the
height and
advantages of N. menziesii
understory
sometimes
but
not
always
sufficient
to
let
it
sometimes
but
not
sufficient
understory
always
reach
canopy before
before the
the faster
N.
fusca?
reach the
the canopy
faster growing
N.
growing fusca?
Second,
differ in either
the promptness
promptness
do the
the species
either the
Second, do
species differ
or the
of
their
response
to
environmental
the magnitude
their
to
environmental
magnitude
response
change?
change?
Three
used to
Threedata
sets were
to address
datasets
were used
addressthese
these questions.
questions.
1.
saplings
in
one
tree-fall
gap
were felled.
in
1. All existing
one
tree-fall
felled.
existing saplings
gap were
different heights
Cross
stem at
at different
Cross sections
sections of each
each stem
were
heights were
of
stems
in
the
gap
aged
determine
the
height
profile
to
determine
the
stems
the
aged
height profile
gap
for
past.
for different
different times
times in the
the past.
2. Canopy
tall understory
understory stems
paired by
by
and tall
stems were
were paired
Canopy and
species.
Again,
cross
sections
from
different
heights
cross
sections
from
different
species. Again,
heights
were aged.
were
aged.
3. Using
basal cross
cross sections
sections of understory
and small
small
Using basal
understoryand
canopy
stems
paired
by
species
and
proximity,
basal
and
stems
canopy
paired by species
proximity, basal
of
area
were
compared
between
members
between
area changes
were
members
changes
compared
each
each pair.
pair.
30....---------------...,
I
•
25
Nf <6
Nf
North
20
•
~
@n
U
!Cl)
E
.sc.
U
•
15
~
4.0
(J)
Nf>18
Nf>18
Nm <6
Nm
Cl)
u
c::::
C,
V)
Nf6-18
Nf 6-18
10
CS
0+---.-------r
o
10
n
o
+
D
Nm >18
Nm
>18
+
Dead
Dead
Nm
Nm 6-18
6-18
-#--r1----::I~-__._-__1
15
20
25
30
in meters
Distance
Distancein
meters
Fig.
for cm DBH
in a gap.
are for
DBH
stems in
codes are
Fig. 1. Map
Map of stems
Species codes
gap. Species
classes.
fallen stems.
classes. Arrows
Arrows indicate
indicate main
main fallen
stems. Ellipse
indicates
Ellipse indicates
Nm =
approximate
borderof canopy
N. fusca, Nm
canopy opening.
opening. Nf = N.fusca,
approximateborder
N. menziesii.
N.
menziesii.
Study area
in unlogged
All sampling
was done
done in
stands in the
the
unlogged stands
sampling was
Maruia
South
Island,
New
Zealand
(42°
13'
S,
MaruiaValley,
South
Zealand
13'
Island,
(42?
Valley,
172°
172? 16'
16' E),
near areas
areas studied
studied for
for forest
forest dynamics
E), near
dynamics
Rose 1990;
(Stewart
& Rose
& Stewart
Stewart1991;
Duncan&
Stewart
1990;Duncan
1991;Stewart
(Stewart&
Burrows 1994;
et al.
al. 1991;
Stewart &
& Burrows
Runkle et al.
al.
1991; Stewart
1994; Runkle
1995).
used for
for the
The stems
stems used
the third
thirddata
data set mentioned
mentioned
1995). The
above
sections of paired
above (basal
came from
fromplots
(basal sections
stems) came
pairedstems)
plots
1 and
and 2 in Stewart
Stewart &
& Rose (1990). These
These forests
forests
contained
contained from
from 175
175 to ca.
ca. 250 stemslha
stems/ha of canopy
canopy
= diameter
(~ 20 cm
diameter at
breast
sized individuals
individuals (>
cm DBH
DBH =
at breast
>
> 1m
=
1.4
of
which
most
trees>
m
tall
and>
height
of
trees
30
and
m),
height
N.fusca.
Stands
tended
to
all-aged,
DBH
DBH were
were N.
Stands
tended
to
be
with
fusca.
all-aged, with
N. fusca
fusca dominants
dominants up
to
400
450
yr
old.
All
stands
N.
to
old.
stands
up
yr
occurred
occurred on
on terraces
with soils formed
formed from
from alluvial
terraces with
alluvial
sand
gravels
containing
variable
mixsandand
and silt
silt overlying
variable
mixoverlyinggravels containing
greywacke,
and
schist
(Bowen
1964;
tures
schist
tures of granite,
and
1964;
(Bowen
granite, greywacke,
Mabin
Mabin 1983).
& Kershaw
Kershaw (1985),
Stewart&
&
1983). Hosking
(1985), Stewart
Hosking &
Rose (1990),
and Duncan
Duncan &
& Stewart
Stewart (1991)
describe
(1990), and
(1991) describe
past disturbance
disturbanceevents
events (insects,
(insects, drought,
windstorms).
past
drought,windstorms).
Methods
Growth of
gap
of saplings
saplings in gap
A gap
valley was
was sampled
Novemthe Maruia
Maruiavalley
gap in the
sampledon November 17,
1).
The
gap
was
selected
to
contain
ber
The
was
1988 (Fig.
selected
to
contain
17, 1988
1).
(Fig.
gap
of
each
species
and
to
new
enough
several
severalsaplings
each
and
to
be
new
to
saplings
species
enoughto
collect information
growth
before
gap
formainformationon
on sapling
before
formasaplinggrowth
gap
tion, and
measure sapling
and old enough
to measure
after
tion,
enough to
sapling growth
growth after
gap
formation.
It
had
6°
slope
and
305°
aspect.
It
had
6?
formation.
and
305?
The
slope
gap
aspect. The
the long
axis
of
the
gap
(the
same
as
the
orientation
axis
orientationof the
the
same
as
the
(the
long
gap
orientation
base to
the fallen
fallen gapmakers,
from base
to top)
orientationof the
top)
gapmakers,from
of
the
surrounding
canopy
was
was 333°.
The height
was
333?. The
the
height
surroundingcanopy was
2 for
about
Gap area
m2
the expanded
about25
25 m.
m. Gap
areawas
was 406 m
for the
expandedgap
gap
set
by
the
bases
of
canopy
(whose
is
set
the
bases
trees
(whose perimeter
perimeter
by
canopy trees
2 for
the
surrounding
m2
for the
the canopy
and 243
243 m
surroundingthe
canopy opening)
opening) and
canopy
gap
(whose
perimeter
is
set
by
a
vertical
proa
vertical
by
canopy gap
perimeter
procanopy opening):
jection of the
was apthe canopy
jection
opening): gap
shape was
apgap shape
proximated
largest two
as an
an ellipse
defined by
the largest
two gap
by the
gap
proximatedas
ellipse defined
living and
axes
perpendicular to
axes perpendicular
each other.
other. For
For all
all living
and
to each
dead stems
and
for
the
canopy
trees
stems within
within the
the gap
for
the
dead
and
trees
gap
canopy
surrounding
gap we recorded
the gap
recorded location
location (to
nearest
(to nearest
surroundingthe
0.1
two
perpendicular
axes),
diameter
at
diameter
at
0.1 m,
m, along
axes),
along
perpendicular
We
destructively
sampled
all
breast
and
height.
breastheight,
and
height,
destructivelysampled
height.
48 living
disks were
stems within
within the
the gap.
were
living stems
gap. Complete
Complete disks
removed
the base,
breast height
removed from
from each
each stem
stem at
at the
at breast
base, at
height
(1.4 m),
at height
and at
at 2 m intervals
intervals starting
and
m), and
height 3 m and
startingat
of
the
stem.
The
231
cross
continuing
for
the
length
The
for
the
the
stem.
231
cross
continuing
length
sections
sections were
were air
dried for
for several
several weeks
weeks and
and then
then
air dried
sanded
using 40, 120,
papers.
The
age
The
sandedusing
and 220 grit
120, and
age of
grit papers.
each
under a binocular
each section
section was
was read
read under
binocular microscope
microscope
using
Henson tree-ring
measuring machine.
machine.
using a Henson
tree-ringmeasuring
We
We assumed
assumed that
that each
each ring
one year's
ring represented
representedone
year's
Nothofagus
sometimes
has
missing
growth.
Although
sometimes
has
growth. Although Nothofagus
missing
and/or
most rings
false rings,
annualgrowth,
and/orfalse
rings, most
rings represent
representannual
growth,
especially
the
faster
growing,
upper
in
and outer
outer secthe
faster
secespecially
growing, upper and
Norton 1983;
Norton &
tions
&
tions of stems
stems (Bussell
1983; Norton
1968; Norton
(Bussell 1968;
Ogden
1987;
Ogden
et
al.
1996).
al.
1987;
1996).
Ogden
Ogden
derived equations
stem height
We derived
to predict
as aa
equations to
predict stem
height as
for
each
stem.
A
stepwise
procedure
function
for
function of age
each
stem.
age
stepwise procedure
(Anon.
used to
to determine
best model
model for
for
was used
determinethe
the best
1990) was
(Anon. 1990)
2
of
some
combination
of
a
(age),
height
as
a
function
as
function
some
combination
(age), aa2,,
height
4
3
aa3 and
used to
to estimate
estimate the
the
and aa4.• These
These equations
were used
equations were
439
439
- Temporal
and diameter growth
for two Nothofagus
Temporal changes
changes in height
height and
growth for
Nothofagus species
species -
each stem
stem for
for several
several specific
height
The
height of each
specific years.
years. The
were
predicted
heights
were
combined
combined
to
to
estimate
estimate
the
the
size
size
predicted heights
distributionof stems
stems in
in the
the gap
distribution
for
for
those
those
years.
Stems
Stems
gap
years.
which had
had died
died before
before we sampled
were not
not included.
which
included.
sampledwere
Oursample
in
therefore
biased
favor
faster
Our
therefore
is
biased
in
favor
of
faster
growing
sample
growing
stems.
stems.
These equations
also were
were used
used to
to calculate
These
calculate estiestiequations also
mated stem
stem heights
at
mated
at
20-yr
intervals.
intervals.
Differences
Differences
bebeheights 20-yr
tween these
these estimated
estimated heights
were
used
to
tween
were
used
to
calculate
calculate
heights
distributionsof 20-yr
frequency
rates for
for both
both
frequencydistributions
20-yr growth
growthrates
species.
Species
differences
differences
were
were
evaluated
evaluated
using
t-tests
t-tests
species. Species
using
An interval
intervalof20
of 20 yr
shouldbe
be long
(Anon.
(Anon. 1990).
1990).An
yrshould
enough
longenough
not to
to be
be influenced
influenced by
short-termevents,
in
not
errors in
events, errors
by short-term
or
outcomes
reading
rings
or
misleading
outcomes
of
the
equations.
the
readingrings misleading
equations.
It should
should be
be short
short enough
It
to generate
reasonable
generate aa reasonable
enough to
size and
and to
be influenced
to be
influenced by
sample
envisample size
by longer-term
longer-termenvironmentalchanges.
ronmental
changes.
consistent significance
A consistent
level of P < 0.05
0.05 will be
be
significance level
in this
used in
this paper.
used
paper.
Relative radial growth
growth ofpaired
of paired stems
Additional
Additionalmeasurements
measurementswere
weretaken
takenfrom
fromtwo
two plots
plots
previously
studied
by
Stewart
&
Rose
(1990).
These
previously studied by Stewart & Rose (1990). These
plots
km apart
in an
were approximately
an old-growth
plots were
apartin
approximately1 km
old-growth
forest
near
Station
Creek,
Rotoroa
Ecological
forest near Station Creek, RotoroaEcological District,
District,
South
SouthIsland.
Island.Data
Dataon
on those
those plots
anddiscs
discs of all
all stems
stems
plots and
> 1.4
1.4 m
m tall
tall were
were collected at
at ground
in NovemNovemgroundlevel in
ber/December
beforethe
the areas
areaswere
were comcomber/December1986,
1986, shortly
shortlybefore
mercially
logged.
mercially logged.
For
For the
the present
selected groups
stems
presentstudy,
study, we selected
groupsof stems
(groups
of
two
with
one
group
of
four)
that fitted
fitted the
the
(groups two with one group four) that
following
criteria:at
at least
least one
one individual
individualof each
each spefollowing criteria:
species, stems
stems similar
similarin
in DBH
DBH and
and height,
and in
in physical
height, and
physical
proximity
«
5
m
apart).
Altogether
we
examined
m
examined 16
16
proximity (<
apart). Altogether
stems
stems of each
each species,
cm DBH
DBH and
3.4 - 25.5
25.5 cm
and
species, ranging
ranging3.4
5.5
5.5 - 27.4 m
m high.
andDBH
DBH did
did not
not vary
high. Height
Heightand
varysignifisignificantly
with
species
but
were
significantly
larger
in plot
cantly with species but were significantlylargerin
plot
1 (Table
2).
(Table 2).
The
The basal
basal discs
from each
discs from
each stem
stem were
were located
located and
and
sanded
as
described
above.
Comparison
of
sanded as described above. Comparison the
the indiindividual
vidual ring-width
series by
the computer
ring-width series
by the
computer program
program
COFECHA
(Holmes
1983)
revealed
COFECHA(Holmes 1983) revealedthat
thatthe
the collection
collection
could
could not
not be cross-dated.
cross-dated.This
This result
resultprecluded
the use
precludedthe
of standard
tree-ring
statistical
analyses.
Tree-ring
standard tree-ring statistical analyses. Tree-ring
widths
then converted
increments of
widths were
were then
converted to annual
annual increments
basal
area
(BAI)
using
computer
software
basal area (BAI) using computer software developed
developed
by
& Fields
the cross-sectional
Fields (1988). BAI is the
cross-sectional
by Phipps
Phipps &
area
produced on the
tree stem.
areaof wood produced
the tree
stem. The
The individual
individual
core
series
of
BAI
were
then
averaged
for
core series
were then averagedfor each
each species
species
and
plot.
and plot.
Height
Height growth ofpaired
of paired canopy
canopy stems
small canopy
one N.fusca
Six pairs
andone
one
trees,one
canopytrees,
pairsof small
N.fusca and
N.
menziesii each,
N. menziesii
of
approximately
equal
DBH,
were
were
each, approximatelyequal DBH,
selected from
from the
standnear
the gap
selected
the stand
near the
(Table 1).
1).
sampled(Table
gap sampled
Pairs
trees were
were selected
selected to
to be close enough
Pairs of trees
enough together
together
to have
have undergone
the same
same climatic
undergone nearly
climatic and
and disturdisturnearlythe
bance
Trees
were
bance history.
Trees
were
destructively
sampled
and
the
and
the
history.
destructivelysampled
each
the
105
sections
age
of
each
of
the
105
sections
estimated
as
above.
estimated
as
above.
age
Predictive
Predictive equations
equations relating
relating height
height to
to age
age were
were develdeveland
used
as
for
the
oped,
and
used
as
for
the
gap
saplings.
oped,
gap saplings.
The
The diameters
diameters of other
other stems
were sampled
plots
stems were
sampledin plots
of 10
10 m radius
radius centered
centered halfway
halfway between
between each
pair of
each pair
>
stems. All stems
stems were
sampled
were sampled
which were
were ~
sampled stems.
sampledwhich
half the
the diameter
diameter of the
the smaller
smaller of the
the two sampled
sampled trees.
trees.
This
This criterion
criterion was used to include
include only
only stems
stems most
most
likely to influence
influence the
the growth
growth of the
the paired
paired stems.
stems.
Table 1. Paired
Paired canopy
canopy stems
stems used
used for
for height-growth
height-growth comparisons.
comparisons. Nf = Nothofagusfusca,
Nothofagus fusca, Nm = N. menziesii.
menziesii.
DBH (cm)
Pair
Pair
1
2
3
4
5
6
(m)
ht (m)
Min. DBH
DBHfor
Distance between
between Min.
Distance
for
living stems
stems
No. of living
Nf
Nm
Nm
Nf
Nm
Nm
stems (m)
(m)
stems
sample
plot sample
Nf
NfJ
Nm l
Nm'
Other
Other
20.3
17.3
10.2
16.8
10.0
10.2
18.8
13.7
10.1
10.1
14.8
9.0
10.7
24.5
21.9
16.3
21.4
13.7
16.3
22.5
14.0
10.6
14.0
13.3
15.0
2.3
1.9
2.5
3.9
2.3
1.9
9.4
6.8
5.1
7.4
*
5.1
8,4,3
8,4,3
22,1,4
6,4,3
22,6,1
22,6,1
6,1,2
6,1,2
11,3,0
37,0,0
37,0,0
8,2,1
0
0
0
0
3,1,2
34,9,1
34,9,1
2
61,16,13
96,15,4
96,15,4
2
All
1Number of species in DBH size classes < 20 cm, 20 - 50 cm, >
~ 50 cm;
cm;
1Number
*Pairs
*Pairs 4 and
and 5 were too close together
together for separate
separate measurements.
measurements.
440
440
Runkle,
J.R. et
et al.
al.
Runkle, J.R.
Results
Results
Table
2. Size
Table 2.
Size class
class distribution
distributionof
of stems
stems used
used to
to measure
measure
relative
relativeradial
radialgrowth
of paired
stems.
growthof
pairedstems.
Growthof
in gaps
Growth
of saplings
saplingsin
gaps
DBH
DBH
(cm)
(cm)
Species
Species
The relationship
of sapling
or core
core height
to measThe
measrelationship of
sapling or
height to
ured age
was
for
43
of
48
ured
was
significant
for
43
of
48
stems
and
acstems
and
acage
significant
2
counted for
for most of
of the
the variation in
in height
counted
(minimum
height (minimum rr2
2 > 0.98 for
= 0.88;
of 48 stems).
=
~ 0.98 for 37 of
0.88; rr2
stems). Gap
Gap saplings
saplings
followed aa variety of growth
followed
curves
with
many
growth
many showing
showing
an increased growth rate
rate in about 1900
1900 (Fig.
an
2). Differ(Fig. 2).
of
the
ent parts
of
the
gap
were
characterized
by
parts
by different
In
growth patterns.
In
the
center
of
the
gap,
stems
of both
patterns.
gap,
and
about
1900
and
N. fusca
and
N.
menziesii
originated
about
1900
and
fusca
originated
N·fusca
N.fusca
N.
N. menziesii
menziesii
Height
Height
(m)
(m)
A.
66
<<10
10
- 20
22 10
10-20
11
~20
>20
44
33
66
22
11
<< 10
10
10
- 20
10-20
~20
>20
11
55
11
66
<< 10
10
- 20
22 10
10-20
11
~20
>20
00
55
22
77
11
11
=-
,
,,
a
"-'
....
0
9-4
Ion
,,
,
,,
,
"
" ",,
,,
,
,, , , .-
-
,,
IOn
v.
~-
, ,,", .-
' ,
1"4
~-
0,
Ioni4n -
----
o0
150
150
50
50
100
100
'
,.
L
...... .-' ",
......... ... _, ...'..,' ,
0
'0
N
-*
200
200
,,
~
--
,',,'
.-.'... ---::"
"',,"'~ ... , , ,
' ~
,
~.,
" "
--- -----
.. -
~--.
.0
0
200
200
00
I
II
I
In
~
22
11
55
11
B.
B.
0~-
'0
Plot
Plot
11
<< 10
10
10
- 20
10-20
~20
>20
I
't'1
N
0
22
*Plots
*Plots 11 and
and22 in
in Stewart
Stewart&
& Rose
Rose (1990)
(1990)
'0
N
N
Plot*
Plot*
11
#.. '
,
,l
~
-
"
1
I
I
150
150
100
100
50
50
ISO
150
100
100
50
50
0
'0
N
oeq
c.
In
0
N
'0
~
a
"-'
....
==
0
_
......
O
0
,,
,,
,,
,
,
,,
,,
0
nm
I
. --
o
-
200
200
150
150
100
100
50
50
1988)
Age (yr before 1988)
00
200
200
0
Age (yr
(yr before 1988)
1988)
Age
Fig. 2.
2. Height
Height growth
growth curves
curves for
for selected
selected saplings
saplings in
in the
the gap.
gap. Solid
Solid lines
lines == N.
N. fusca,
fusca, dashed
dashed lines
lines == N.
N. menziesii.
menziesii. Curves
Curves are
are
Fig.
polynomial, usually
usually 3rd
3rd order,
order, fitted
fitted to
to actual
actual height-age
height-age values.
values. A.
A. Fast
Fast growing
growing stems
stems in
in gap
gap center.
center. B.
B. Slow
Slow and
and steady
steady growth
growth by
by
polynomial,
stems
stems in
in southeastern
southeastern part
part of
ofgap.
gap. C.
C. Rapid
Rapid and
and recent
recent growth
growth by
by previously
previously suppressed
suppressed stems
stems in
in southwestern
southwestern part
part of
of gap.
gap. D.
D. Larger
Larger
stems
of gap.
gap.
stems which
which had
had grown
grown rapidly
rapidly recently
recently following
following suppression
suppression earlier
earlier in
in northwestern
northwestern part
part of
- Temporal
Temporal changes
Nothofagus species
changes in height
height and diameter growth
growth for two Nothofagus
species 50
40
A.
40
(/)
Cl)
a)
~
ns
>
o
~
0
C
4
+J
c:
441
441
11
Nf - gaps
D
Nm - gaps
B.
30
11
Nf - pairs
0
Nm - pairs
30
3020
020-
20
20-
Cl)
u
a..
.
0O~~~~~~10
10-
"-
Cl)
'
10
100o
o
I
O
~
0ouo
10
Lr)
L
0
O On~
~
u-_
0O
Lr)
L O0
I
Lr)
L
0O
No iN M
eni
io M q:
Lr) OO
0
~
I
I
Lr)
LA
vi
vi
oLnL
i
r
0
0
Lr)
L
O
LO
O
~
o c::i
c::i
o- o-
~
Lr)
LO
O
~
N
cNjo ui
0O
Lr)
Ln
0
u q:
0 M
N M
Lr)
Lm
~
0
|
Lr)
Ln
u
vi
ui vi
Growth
Growth (m/20
(m/20 yr)
yr)
Fig. 3. Frequency
20-yr simulated
both species
as paired
paired stems.
= N.fusca;
N.fusca;
distributionof 20-yr
simulatedgrowth
ratesfor
for both
and B)
stems. Nf =
A) in gaps
B) as
Fig.
growthrates
Frequencydistribution
species A)
gaps and
Nm = N.
N. menziesii.
menziesii.
or slowed
either
growth
eitherhave
have grown
fast ever
ever since
since or
slowed their
theirgrowth
grownfast
when
became
overtopped
(Fig.
2A).
The
southeastwhen they
The
became
southeast2A).
they
overtopped(Fig.
ern
ern part
dominated by
several large
N.
the gap
by several
part of the
gap is dominated
large N.
in
menziesii,
in
the
late
1700s
or
midwhich originated
the
late
or
mid1700s
menziesii, which
originated
1800s
and which
shown slow, steady
1800s and
which have
have shown
steadygrowth
growth(Fig.
(Fig.
2B). The
part of the
contains
several
The southwestern
the gap
southwesternpart
contains
several
gap
stems
but which
which have
have grown
which
stems which
since 1900
1900 but
grown rapidly
rapidlysince
experienced
some
suppression
earlier
(Fig.2e).
The
some
earlier
The
2C).
experienced
suppression
(Fig.
northwestern
part of the
contains
some
larger
stems
the gap
contains
some
stems
northwesternpart
larger
gap
which
but
which also
also have
have grown
grown relatively
relatively rapidly
rapidly recently
recently but
which underwent
underwent some
earlier
(Fig.
2D).
In
In
which
some suppression
earlier
2D).
suppression
(Fig.
agreement
with
the
literature
(e.g.
Wardle
1984)
N.
with
the
literature
Wardle
N.
1984)
agreement
(e.g.
menziesii was
fusca to
menziesii
was more
more likely
thanN.
N. fusca
to have
have underunderlikely than
gone
long
periods
of
suppression.
N.
fusca
apparently
N.
gone long periods suppression. fusca apparently
usually
at
or dies.
dies. However,
However, at
usually grows
grows relatively
relatively rapidly
rapidly or
least one
N. fusca did
suppresleast
one stem
stem of N.fusca
did survive
surviveaa lengthy
lengthy suppression
period (Fig.
N. menziesii
grew about
about as
sion period
Some N.
as
menziesiigrew
2D). Some
(Fig. 2D).
rapidly
as
N.fusca.
N.
rapidly
fusca.
The
patterns shown
The patterns
shown by
these selected
stems are
are
selected stems
by these
representative
of
the
pattern
for
all
stems
(Fig.
for
the
all
stems
representative
pattern
(Fig. 3).
Although
the
ranges
of
20-yr
growth
intervals
were
the
intervals
were
Although
ranges 20-yr growth
similar
(0.05
4.75
m/20
yr
for
N.
similar for both species
4.75
m/20
(0.05
yr
species
N.
fusca,
0.01
-4.47
m/20
yr
for
menziesii),
fusca
-4.47
N.
m/20
menziesii),
fusca,
yr
fusca
growth
and more
more variable
variable(N.
(N.
growthwas significantly
significantly greater
greaterand
=
=
=
n
fusca:
n
=
48,
mean
=
2.37,
S.D.
=
1.11;
menziesii:
S.D.
N.
menziesii:
2.37,
fusca:
= 192, mean =
= 1.12,
= 0.68).
=
S.D. =
Few stems of
of N.
1.12, S.D.
0.68). Few
fusca showed
very slow
showed the very
slow growth
common in N.
fusca
growth rates common
menziesii.
menziesii. Few
Few stems of
of N. menziesii
menziesii showed
showed the fast
growth
N. fusca.
fusca.
common in N.
growth common
The
The relative
two species
relative dominance
dominance of the
the two
the
species in the
gap
changed
over
time,
judging
from
the
estimated
from
over
the
estimated
time,
gap changed
judging
height distributions
times N. menziesii
distributions(Fig.
menziesii
height
(Fig. 4). At all times
outnumbered
N. fusca,
fusca, especially
outnumberedN.
the smaller
smaller
especially among
among the
stems. This numerical advantage
of
menziesii
of
N.
menziesii
is
advantage
consistent
Stewart
&
Rose
consistent with the literature (e.g.
Rose
(e.g.
1990;
Stewartet al.
al. 1991;
al. 1996)
and with
with
1990; Stewart
1991; Ogden
1996) and
Ogden et al.
the
around
the
paired
canopy
trees
used
this
the plots
around
the
in
trees
used
this
plots
paired canopy
study
(Table
1).
However,
N.fusca
gradually
increased
increased
However,
(Table
1).
N.fusca gradually
study
In 1889,
among
the taller
taller stems
stems in the
the gap.
the tallest
tallest4
1889, the
among the
gap. In
in the
stems
were
N.
menziesii.
In
1988
the
tallest
the gap
were
In
stems in
N.
menziesii.
the
tallest2
1988
gap
stems
N. fusca.
fusca. Thus
balance
stems were
were N.
Thus a competitive
balance
becompetitive
tween
in
this
gap
occurred
because
the
tween the
the two species
this
occurred
because
the
species
gap
greater
initial
height
and
numerical
advantages
of
initial
and
numerical
N.
greater
height
advantages N.
menziesii
would
ensured that
menziesii ensured
that some of its saplings
would
saplings
reach
faster growth
N. fusca
fusca
reach the
the canopy
the faster
canopy while the
growth of N.
ensured that
also
would
reach
the
ensured
that some of its
its saplings
would
reach
the
saplings
canopy.
canopy.
Note that
Fig. 4 does
Note
that Fig.
does not
not include
include stems
stems which
which died
died
before we sampled.
before
sampled.
Height growth
growth ofpaired
Height
of paired canopy
canopy stems
Stem or core height
height was significantly
significantly related to age
age
12 stems
for
N.fusca andN.
picked to
for all
all 12
stemsof N.fusca
andN. menziesii
menziesiipicked
to be
close in DBH and
relationship acand in location
the relationship
location and
and the
ac2=
2
= 0.89;
counted
countedfor
for most
the variation
most of the
variation(minimum
0.89; rr2
(minimumrr2
>
12 stems).
In 5 of 6 pairs
~ 0.98 for
pairs N.
N. menziesii
for 10
10 of 12
menziesii
stems). In
was present
present before
before N.
fusca and
initial size
was
N. fusca
and had
an initial
had an
advantage
all cases,
N.
however,in all
cases, N.
advantage(Fig.
(Fig. 5). Eventually,
Eventually,however,
In
fusca
grew
taller.
In
part
the
larger
size
at
present
may
taller.
the
at
fusca grew
part larger
presentmaybe
an
procedure: for
an artifact
artifactof the
the selection
selection procedure:
for a given
DBH
given DBH
N.fusca
usually
will
taller
thanN.
menziesii
(Runkle
N.
be
taller
than
N.
menziesii
(Runkle
fusca usually
et al.
rates of the
two species
al. 1995).
The growth
the two
were
1995). The
growth rates
species were
similar for
similar
years
for
most
pairs,
with
N.
fusca
for many
for
with
most
N.
many years
pairs,
fusca
Runkle,
J.R. et al.
al.
Runkle,I.R.
442
442
2020
19
1918
181717
16
1615
151414
.-.... 13
12_E 12
.......... 11
....., 10
109
.r:.
.
9C)
8
8)
'Q)
7
7')
6
5
4
3
3-'n5
2
21
0
0-
•
20
2019
191818
1717
16
1615
151414
1313-3
12
1211
10
9
8
7
6
5
4
43~
3
2
1
?E
0
Nf-l 889
Nf-1889
E Nm-1
889
D
Nm-1889
13-
::r:
;
0 1 2 3 4 5 6 7 8 9 10
•
20
2019
191818
1717
16
1615
151414
13
12
12
11
10
9
8
7
6
5
5.
4
3
2
1
00
Nf-l 929
Nf-1929
D
O Nm-1929
0 1 2 3 4 5 6 7 8 9 10
•
*
•
Nf-1959
Nf-1959
Nm-1959
Dl Nm-1959
I
-
1
0
2
3
4
5
6
20-1
19
*
Nf-1988
Nf-l 988
19i
18
17 16
16D
O Nm-1988
Nm-1988
15
14
13
12
1111
10
9
8
7
65
4
43
2
11
00 0
I
I
I
0 1 2 3 4 5 6 7
8
No. of Stems
in Gap
Stems in
Gap
4. Estimated
Estimated
distributions
in the
forfour
fourtime
Fig.
height
of saplings
time periods
periods for
alive in
N. fusca, Nm
Nm = N.
thegap
forsaplings
in 1988.
N.
1988.Nf = N.fusca,
Fig. 4.
heightdistributions
saplingsin
gapfor
saplingsalive
menziesii.
menziesii.
taller only
in the
getting
the last
last 20-50 years.
Some errors
errors
getting taller
only in
years. Some
estimating
ages
for
the
older,
more
slowly-growing
for
the
more
older,
estimating ages
slowly-growing
sections
sections of some
some stems
stems were
were apparent:
for some
some stems
stems
apparent:for
several
similar
estimates
of
severalcross
cross sections
in a row
sections in
row gave
similar
estimates
gave
stem age.
stem
This
problem
was
not
nearly
as
important
for
This
was
not
as
for
age.
problem
nearly important
the
parts of the
the upper,
more rapidly
the stem.
stem.
upper,more
rapidlygrowing
growing parts
Both
had
a
wide
range
of
values
for
Both species
had
a
wide
for 20-yr
values
species
range
20-yr
menziesii:
0.00growth (N.fusca:
N.
0.000.20-7.59 m/20 yr;
growth
(N.fusca: 0.20-7.59
yr;
4.90 m/20
from
N.
fusca
with only
one reading
from
N.
m/20 yr),
yr), with
only one
fusca
reading
substantially
thanthe
the maximum
maximumgrowth
observed
substantiallygreater
greaterthan
growthobserved
fusca growth
for N. menziesii (Fig.
3). Overall N. fusca
(Fig. 3).
growth was
N. menziesii
significantly
than N.
fasterthan
menziesiialthough
not signifisignificantlyfaster
althoughnot
signifi= 3.12, S.D.
cantly
=35, mean =
(N.fusca: n =
cantly more variable (N.fusca:
= 1.55; N. menziesii: n =
= 36, mean =
= 1.98, S.D. =
= 1.30).
=
Ln
N
0
Lf)
Ln
c.'
N
N
~
0
~
Nf
N
0
Ln
Ln
N
Nf
- - -0--
0
N
pairs
Changes
the height
distributionsof these
these six pairs
Changesin the
heightdistributions
of stems
stems
stems over
over time
time match
match the
the results
results of the
the gap
stems
gap
N. menziesii
had an
(Fig.
Once again,
menziesiihad
an initial
initial advanadvan6). Once
(Fig. 6).
again,N.
tage
which
ensured
that
some
stems
would
reach
the
which
ensured
that
some
stems
would
reach
the
tage
of
N.fusca
ensured
that
canopy
while
the
faster
growth
while
the
faster
N.
ensured
that
canopy
growth
fusca
it also
also would
would be well represented
in the
the canopy.
The
representedin
canopy. The
outcome
relative advantages
is
that
N.
menziesii
outcomeof these
these relative
that
menziesii
N.
advantages
dominated
dominatedthe
the shorter
shortersize classes,
classes, though
thoughoccasionally
occasionally
andN.fusca
dominated
the
it reached
reachedthe
the canopy,
and
N.
dominated
the larger
fusca
canopy,
larger
size classes
classes (Table
(Table 1).
1).
N
-0--
0
Ln
N
L,
Ln
Nf
0
.-...
Ln
-
Lt')
L,
E
Lt')
0
0o
'-'"
4-J
+-J
:::c
I
00-
0
0
.,
0'"
Ln
Ln
0
Ln
Ln
Ln
,
,
0
0
0
300
300
150
150
,~
0
p
0
0
I20
200
200
100
100
0
200
200
100
100
0
200
200
0
0
0
1
100
100
0
200
200
100
100
0
100
100
50
Age (yr)
(yr)
Age
Fig. S.
Height growth
paired canopy
N.fusca,
N. menziesii.
5. Height
curves for
for paired
stems. Pairs
Pairs 1-6
1-6 are
are in order,
menziesii.
order,left to right.
Fig.
growthcurves
fusca, Nm = N.
canopy stems.
right.Nf = N.
0
- Temporal
and diameter growth
Temporal changes
changes in height
height and
growth for two Nothofagus
Nothofagus species
species -
"..........",
E
"-""
+J
4-r
-c
or:.
C)
0Ci)
I
:c
2525
2323
2121
19
191717
15
1513
131111
9
77553311-
2525
23- 11
23
* Nf-1889
Nf-1889
21 21
Nm-1889
19- DI1 Nm-1889
19
1717
1515
1313
11
11
997755331
0
I
I
I
1
2
3
4
25
23
21
19
17
15
13
11
9
7
5
3
1
11
* Nf-1929
Nf-1929
0I Nm-1929
Nm-1929
0
I
I
1
2
3
11
25
23
21
19
17
15
13
11
9
7
5
3
1
Nf-1959
0 Nm-1959
0
1
2
3
4
443
11
Nf-1988
D
Nm-1988
1
0
2
3
No.
No. of paired
pairedstems
Estimated height
Fig.
= N.fusca,
Nf =
N. fusca, Nm =
= N. menziesii.
Fig. 6. Estimated
menziesii.
height distributions for the paired
paired canopy
canopy stems for four time periods.
periods. Nf
3
3 r---------------------.,
Plot 1
2
2 r-------------------.,
oE
0
c-
C/)
E
o
2
2
Plot 1
1
8
Cr
cC/)
0
N. menziesii
Vr
c
';i,'1 ~
_r
1
",~
I
"
'If
\-' \.. . '-",: 'I
.,j
'I
,
"
-1
"\-
U
\
,
OL--.L.....-.L.....-L.-..-Il..-.-.J--J-----I---L----L----L----I..---l..---l..----L----L-----L---L..-J
0
1900 1910
1910 1920
1920 1930
1930 1940
1940 1950
1950 1960
1900
1960 1970 1980
1980 1990
1990
I i ,
I
I,
i,
i
.
I
.
I .
I .
-2 L--"--'---'---L.-..-IL.-...-.JL.-...-.JL...--l--J--J--J--J--I---l-----L---L----I.---.J
-2
1900 1910
1900
1910 1920
1970
1980
1920 1930
1930 1940
1940 1950
1950 1960
1960 1970 1980 1990
1990
YEAR
YEAR
YEAR
YEAR
I
33 . - - - - - - - - - - - - - - - - - - - - - . ,
Plot 2
4
Plot 2
E
0
(,
cC.)
C/)
cn
3
E
0
cc-
C/)
cn
«
i,
"
2
ax
0i
~
C)
c:
Q)
a)
'0)
Jg
al
i:5
CI
«
<r
rn
al
00'---L.-..-I'----Jl..-.-.J-----I-----I---L----L----I..----I..----I...----L---'----l.--..1....---I..----l.-----l
1900
1900 1910
1910 1920
1920 1930
1930 1940
1940 1950
1950 1960
1960 1970
1970 1980
1980 1990
1990
YEAR
YEAR
Fig. 7.
7. Mean
Mean growth
growth expressed
expressed as BAI
BAI (basal
(basal area increment)
increment)
Fig.
for Nfusca
N. menziesii
N fusca and
andN.
menziesii since
since 1900.
1900. Solid
Solid lines
lines ==N.fusca,
N.fusca,
dashed
dashed lines
lines = N. menziesii.
menziesii. A.
A. Plot
Plot 1. B.
B. Plot
Plot 2.
2
1
0
,2-LZ
111/M ulS
-1
-1
1900 1910
1910 1920
1920 1930
1930 1940
1940 1950
1950 1960
1960 1970
1970 1980
1980 1990
1990
1900
YEAR
YEAR
Fig. 8.
8. Differences
Differences in mean
mean basal area increments
increments (BAI)
(BAI) since
since
Fig.
1900. N. menziesii
menziesii value
value minus
minus N.fusca
N.fusca value.
value. A.
A. Plot
Plot 1. B.
B.
1900.
Plot 2.
Plot
444
Runkle,
J.R. et al.
al.
Runkle,I.R.
Relative radial
radial growth
growth ofpaired
understory stems
stems
Relative
of paired understory
The
two species
plots 1 and
The two
and 2 have
have grown
differspecies in plots
grown differently
since
1900
in
response
the
same
disturbance
since
1900
to
the
same
disturbance
ently
response
regime
both
and 8).
Growthfor
for both
both species
8). Growth
regime (Figs.
(Figs. 7 and
species in both
plots
was
low
in
the
early
1900s
then
increased
about
was
the
1900s
then
increased
about
plots
early
1945,
both species
plot 1 and
for both
and especially
for N.
N.
1945, for
species in plot
especially for
menziesii
plot 2 (Fig.
7).
This
timing
correlates
with
menziesiiin plot
This
correlates
with
(Fig.
timing
peaks
tree mortality
plot 1 and
from 1938-1951
1938-1951 in plot
and
peaks in tree
mortalityfrom
1934-1955
plot 2 (Stewart
1934-1955 in plot
& Rose
Rose 1990).
Growth
(Stewart &
1990). Growth
since
since 1945
has been
been high
1945 has
butvariable
variablefor
for both
bothspecies
high but
species in
both plots.
In
both
In
plot
1,
N.
menziesii
grew
slightly
but
N.
menziesii
1,
plots.
plot
grew slightly but
consistently
faster
than
N.
fusca
during
the
period
faster
than
N.
the
consistently
fusca during
period of
slow growth
(Fig.
8A).
Since
1945
the
relative
growth
Since
1945
the
relative
8A).
growth (Fig.
growth
rates
have fluctuated
between
years.
In
plot 2
rates have
fluctuatedgreatly
In
between
greatly
years. plot
both species
grew
at
about
the
same,
slow
rate
in the
the
both
at
about
the
rate
same,
species grew
N.
menziesii
has
grown
early
1900s
but
since
about
1945
but
1900s
since
about
1945
N.
has
menziesii
early
grown
consistently
faster (Fig.
8B).
consistentlyfaster
(Fig. 8B).
Discussion
Competition
usually occurs
forest trees
trees usually
occurs for
for
Competitionamong
among forest
light,
moisture and
nutrients (Cannell
Grace
and nutrients
& Grace
(Cannell &
light, soil moisture
1993;
Nambiar &
& Sands
Sands 1993),
evidence from
from
1993; Nambiar
1993), although
althoughevidence
moist, temperate
zone
forests
suggests
that
light
has
the
zone
forests
that
has
the
moist,
temperate
suggests
light
strongest
influence
on
sapling
growth
and
survival
influence
on
and
survival
strongest
sapling growth
(Pacala
in light
~ 80%
al. 1994).
variationsin
at >
80%
(Pacalaet al.
1994). Slight
Slight variations
light at
full shade
full
and
survival
rates
of
shade affect
affect relative
relative growth
and
survival
rates
growth
coexisting
saplings
(Pacala
et
al.
1993,
1994;
Peters
et
al.
Peters
1993,
1994;
(Pacala
coexisting saplings
al.
temperate
zone
forests
also
al. 1995).
Tree species
in
forests
also
1995). Tree
species temperate
respond
between treefall
treefall
to environmental
environmentaldifferences
differences between
respond to
gaps
treefall
gaps
different sizes and
and within
within single
treefall
gaps of different
single
gaps
(Runkle
Runkle &
& Yetter
Yetter 1987;
Veblen
1985, 1990;
1990; Runkle
(Runkle 1985,
1987; Veblen
1992;
McClure &
better
& Lee 1993).
are better
1992; McClure
1993). Some species
species are
able
temporal
variation
in
light
availability
able to
to exploit
variation
exploit temporal
light availability
than
others by
than others
their induction
induction responses
to
by hastening
hastening their
responses to
the
the light
environment,
e.g.
to
light
flecks
which
appear
to
which
environment,
light
e.g. light
appear
over the
over
the leaves for
for only
short periods
&
(Poorter &
only short
periods (Poorter
Oberbauer
Oberbauer1993).
1993).
N.
andN.
N. fusca and
N. menziesii
differ in their
menziesiidiffer
theirlight
light requirerequirements. N.
ments.
N. menziesii
the most
most shade
the
menziesii is the
shade tolerant
tolerantof the
beeches (Manson
New Zealand
Zealand beeches
Wardle 1984).
1974; Wardle
(Manson 1974;
1984).
The relative
relativeproportion
The
proportion of stems
N. menziesii
N.
stems of N.
menziesiiand
andN.
fusca in different
differentsize classes,
as found
found here
here (Table
classes, as
(Table 1)
1)
fusca
andby
and
by others,
this
generalization
(Ogden
1985;
this
others,supports
1985;
supports generalization(Ogden
Stewart
& Rose
Ogden et al.
Stewart&
Rose 1990;
Stewartet al.
al. 1991;
al.
1990; Stewart
1991; Ogden
1996).
N.
fusca
is
more
abundant
small
in
N.
more
abundant
small
1996). Typically,
fusca
Typically,
seedling
classes. However,
resultsin
However,high
seedling size classes.
high mortality
mortalityresults
the
the sapling
and
small
tree
size
classes
being
dominated
and
small
tree
classes
dominated
sapling
being
by N.
N. menziesii.
menziesii. N.
N. fusca
fusca often
dominates the
larger
often dominates
the larger
by
canopy
N. menziesii
classes. N.
menziesii is hypothesized
to
canopy size classes.
hypothesized to
dominate
the forest
small
disturbances
such
dominatethe
forest following
small
disturbances
such
following
as treefall
as
N. fusca
fusca is thought
thought to
to dominate
treefall gaps
while N.
dominate
gaps while
after
disturbances (Ogden
afterlarge-scale
Stewart&
&
1988; Stewart
large-scale disturbances
(Ogden 1988;
Rose
et
al.
1996).
This
dichotomy
is
not
Rose 1990;
This
al.
not
1990; Ogden
1996).
Ogden
dichotomy
absolute.
N. menziesii
to reproduce
both
absolute.N.
menziesiiis known
known to
afterboth
reproduceafter
small
disturbances,
at
least
partly
as
a
function
at
small and
andlarge
least
as
a
function
disturbances,
partly
large
of the
the environment:
N. menziesii
environment:in wetter
wetterenvironments
environmentsN.
menziesii
behaves more
N.fusca
(Stewart
1986).
N.fusca
behaves
morelike N.
can
(Stewart
1986).
fusca
N.fusca can
reproduce
both
in
gaps
and
after
larger
disturbances
both
and
after
disturbances
reproduce
gaps
larger
(Stewart
al. 1991;
Runkleet al.
al. 1995).
because
1991; Runkle
(Stewartet al.
1995). Also, because
both species
disperse
very
slow
I
y
and
therefore
take a
both
and
therefore
take
species disperse very slowly
long
time
to
reinvade
areas
from
which
they
have
been
time
to
reinvade
areas
from
which
have
been
long
they
eliminated,
unlikely that
been excluded
that either
either has
has been
excluded
eliminated,it is unlikely
on a regular
basis from
both are
from locations
locations where
where both
now
are now
regularbasis
present
(Wilson
&
AlIen
1990;
Leathwick
&
Mitchell
Allen
&
Leathwick
&
Mitchell
1990;
present (Wilson
1992;
two species
in
al. 1996).
The two
do differ
differ in
1992; Ogden
1996). The
Ogden et al.
species do
their fine-scale
responses to
N.
fusca
increases
their
fine-scale responses
to light:
N.
increases
in
light: fusca
relative
importance as
size
increases;
N.
menziesii
relative importance
as gap
N.
menziesii
increases;
gap
seems
take advantage
temporary (lastseems better
betterable
able to
to take
(lastadvantageof temporary
ing
minutes
to
hours)
increases
in
light
intensity
minutes
to
increases
southof
hours)
ing
light intensitysouth
gap
center(Runkle
al. 1995).
(Runkleet al.
1995).
gap center
N.fusca
andN.
menziesii
differ in other
N.
and
N.
menziesii
differ
otherways
which
fusca
ways which
might
explain
their
coexistence.
N.
fusca
dominates
their
coexistence.
N.
dominates
fusca
might explain
sites
better drained
nutrients than
sites which
whichare
arebetter
drainedand
andricher
richerin nutrients
than
those dominated
by N.
N. menziesii
those
dominatedby
menziesii (Stewart
al. 1993;
1993;
(Stewart et al.
Ogden
al. 1996).
Both species
aresensitive
sensitiveto
to droughts
1996).Both
Ogdenet al.
speciesare
droughts
but N.
N. fusca
fusca is more
(Manson 1974;
but
more sensitive
sensitive (Manson
1974; Hosking
Hosking
&
N.fusca
& Kershaw
Kershaw1985).
moresensitive
sensitive to
to temperafusca is more
1985).N.
temperature
extremes (Manson
& Norton
Norton 1988).
tureextremes
1974;Ledgard
1988).
(Manson1974;
Ledgard&
Both
can
suffer
damage
from
insects
but
N.
Both species
can
suffer
from
insects
but
N.
species
damage
in
fusca
is
more
susceptible
to
pinhole
borers,
insects
in
more
to
insects
borers,
fusca
susceptible pinhole
general,
and
heart
rots
(Milligan
1974;
Litchwark
1978;
and
heart
rots
Litchwark
1974;
1978;
general,
(Milligan
Hosking
Norton 1988).
& Norton
& Kershaw
Kershaw1985;
1985; Ledgard
1988).
Ledgard&
Hosking &
undergone recent
None of our
our sites
sites had
had undergone
recent large-scale
large-scale
disturbances. Hosking
disturbances.
& Kershaw
Kershaw(1985) reported
masHosking&
reportedmasin
sive mortality
in
1978-1980
of
N.
fusca
areas
near
N.
areas
near
1978-1980
fusca
mortality
ours,
probably caused
caused by
by severe
in
1969-1971
severe droughts
1969-1971
ours,probably
droughts
and
by scale
attacks. Stewart
and 1976-1978
followed by
scale insect
insect attacks.
1976-1978 followed
Stewart
& Rose (1990)
that small
peaked
&
found that
small disturbances
disturbancespeaked
(1990) found
about
the plots
plots from
about 1934-1955
from which
which some
some of our
our
1934-1955 in the
data
to the
the estabdatacome.
come. These
These disturbances
disturbancesdid
did not
not lead
lead to
establishment
but to
to increased
by stems
lishmentof new
new stems
stems but
increasedgrowth
stems
growthby
already
present.
Stewart
et
al
(1991)
found
evidence
of
al
Stewart
found
evidence
(1991)
alreadypresent.
minor
periods from
to
minorreleases
releasesin several
severaldifferent
differentperiods
from 1930 to
1981.
& Stewart
correlaDuncan &
Stewart (1991)
used spatial
correla1981. Duncan
(1991) used
spatial
tions
tree mortality
clustered in
tions to
to indicate
indicate that
that tree
was clustered
mortality was
groups
of
two
to
three
trees
(i.e.
individual
treefall
gaps)
two
to
three
trees
individual
treefall
(i.e.
groups
gaps)
within
clusters,
indicating
that
the
same
storm
or
withingreater
that
the
same
or
storm
clusters,
greater
indicating
season
and
probably
other
season had
had led to several
several small
small gaps
and
other
gaps
probably
breakages too
too small
detected.
small to be detected.
breakages
Under
this disturbance
disturbance regime,
the two
two species
Underthis
were
regime,the
species were
balanced in
their competitive
abilities.
For
decades,
stems
in their
balanced
abilities.
For
stems
decades,
competitive
of the
the two
atvery
similarrates
ratesto
to each
each other
other
two species
very similar
species grew
grew at
(Fig.
2).
Both
species
survived
long
periods
of
suppressurvived
Both
(Fig.
species
long periods suppression,
N. menziesii
than N.
fusca (Fig.
menziesii moreso
moreso than
N. fusca
sion, although
althoughN.
(Fig.
2). Both
grew
rapidly,
although
N.
fusca
Both species
N.
more
species grew rapidly, although fusca more
- Temporal
changes in height
Nothofagus species
Temporal changes
height and diameter growth
growth for two Nothofagus
species menziesii (Fig.
consistently
3). Both species
consistently than N. menziesii
(Fig. 3).
species
although
N.
fusca
more
often than N.
reached the canopy,
canopy, although N.fusca
menziesii (Table
4-- 6).
(Table 1, Figs.
6). N. menziesii increased
Figs. 4
growth
take
advantage
of
opportunities
of
to
growth
advantage
opportunities in the 1940s
more than
than N.fusca,
N. fusca, perhaps
perhaps due to its increased resistance
drought (Figs.
to insect damage
8).
(Figs. 7 and 8).
damage and drought
The relative advantages
of
of
the two species
species varied
advantages
over time. For some
some decades
decades and years
menziesii
years N. menziesii
grew
faster;
for
some,
N.fusca
grew
faster.
Conditions
Conditions
N.
faster;
fusca grew
grew
do not remain constant, especially
species
especially since neither species
is likely
likely to reach the canopy
canopy in a single
single treefall gap
gap
(Ogden et al. 1991).
1991). Therefore, each stem experiences
experiences a
(Ogden
continually
envienvironment. Changes
Changes in the envicontinually changing
changing environment.
ronment may
sometimes
favor
one
species,
sometimes
sometimes
sometimes
may
species,
tolerant, with
the other. Because
Because both species
are shade tolerant,
species are
low mortality
mortality rates, they
each
can
survive
a
few years
low
of
years of
they
unfavorable conditions,
both
species
to
persist
conditions, allowing
species persist
allowing
in the stand.
Acknowledgements.
We thank
thank Larry
Burrows and
and Diane
Diane
Acknowledgements. We
Larry Burrows
in the
Carter
for help
the field.
field. We
We thank
thank Dave
Dave Norton,
Laura
Carterfor
Norton, Laura
help in
Conkey,
Andi Lloyd
andRobert
for assistance
RobertWhitmoyer
assistancewith
with
Conkey,Andi
Lloyd and
Whitmoyerfor
was
tree
tree ring
Financial assistance
assistance for
for lR.
J.R. Runkle
Runkle was
ring analysis.
analysis. Financial
received
the Research
receivedfrom
fromR.
R. Kreps
andthe
ResearchCouncil
Counciland
andCollege
Krepsand
College
This
of Science
and Mathematics
Mathematicsof Wright
State University.
Science and
University.This
WrightState
study
was
also
partially
funded
by
the
Zealand
Department
was
also
funded
the
New
Zealand
by
Department
study
partially
of Conservation.
manuscript were
comments on
on the
the manuscript
were
Conservation.Useful
Useful comments
received
receivedfrom
fromJ.B.Wilson
J.B.Wilsonand
andtwo
two anonymous
reviewers.
anonymousreviewers.
References
Anon. 1990.
Procedures Guide.
Version6. 3rd.
3rd.Ed.
Ed. SAS
SAS
Anon.
1990. SAS
SASProcedures
Guide. Version
Institute,
NC.
Institute,Cary,
Cary,NC.
Allan, H.H.
H.H. 1961.
1961. Flora ofNew
Zealand.Vo!.
Vol. 1.
1. Government
Government
Allan,
of New Zealand.
Printer,
N.Z.
Printer,Wellington,
Wellington,N.Z.
Map
Bowen, F.E.
1964. Sheet
Sheet 15
15 - Buller
Buller(1st
F.E. 1964.
(lst ed.).
Bowen,
ed.). Geological
Geological Map
ofNew
Zealand
1
:250000.
Department of Scientific
and
New
Zealand
000. Department
Scientific and
1:250
of
Industrial
IndustrialResearch,
Research,Wellington.
Wellington.
Zealand trees.
Bussell,
1.
W.T. 1968.
1968. The
The growth
some New Zealand
trees. 1.
Bussell, W.T.
growthof some
Growth in
natural conditions.
N.Z. J.
J. Bot.
Bot. 6:
in natural
6: 63-75.
Growth
conditions.N.Z.
63-75.
light:
Cannell,
J. 1993.
for light:
M.G.R. &
& Grace,
1993. Competition
Cannell, M.G.R.
Grace, J.
Competitionfor
Can.
J.
For.
detection,
measurement, and
and quantification.
Can.
J.
For.
detection,measurement,
quantification.
Res. 23:
23: 1969-1979.
Res.
1969-1979.
Denslow, J.S.
J.S. 1980.
partitioning among
rainfor1980. Gap
Denslow,
Gap partitioning
amongtropical
tropicalrainforBiotropica 12
est trees.
trees.Biotropica
12 (Supplement):
(Supplement):47-55.
Duncan,
R.P. &
& Stewart,
G.H. 1991.
The temporal
andspatial
1991. The
Duncan,R.P.
Stewart,G.H.
temporaland
spatial
Res. 21:
21:
analysis
tree age
For. Res.
distributions.Can.
Can. J.
J. For.
age distributions.
analysis of tree
1703-1710.
1703-1710.
Hill, R.S.
R.S. &
& J.Read.
J.Read.1991.
1991. A revised
revisedinfrageneric
classification
Hill,
infragenericclassification
of Nothofagus
Nothofagus (Fagaceae).
Bot. J.
J. Linn.
Linn. Soc.
105: 37-72.
37-72.
Soc. 105:
(Fagaceae).Bot.
Holmes, R.L.
R.L. 1983.
1983. Computer-assisted
controlin treetreeHolmes,
Computer-assistedquality
qualitycontrol
ring dating
measurement. Tree-Ring
and measurement.
Bull. 43:
43: 69-75.
ring
datingand
Tree-RingBull.
D.J. 1985.
beech death
Hosking, G.P.
G.P. &
& Kershaw,
Red beech
deathin the
the
1985. Red
Kershaw,D.J.
Hosking,
N. Z.
J. Bot.
Bot.
Maruia
Valley, South
Zealand. N.
Z. J.
MaruiaValley,
South Island,
Island, New Zealand.
23:
23: 201-211.
201-211.
445
Leathwick, J.R.
Mitchell, N.D. 1992.
pattern, climate
& Mitchell,
climate
J.R.&
1992. Forest
Forestpattern,
Leathwick,
and
central North
North Island,
and vulcanism
vulcanism in central
Zealand.J.
J.
Island, New Zealand.
Veg.
3: 603-616.
603-616.
Sci. 3:
Veg. Sci.
Norton, D.A. 1988.
Ledgard,
N.J. &
& Norton,
1988. Shoot
Shoot growth
growthin 2-3 year
year
Ledgard,N.J.
Nothofagus seedlings.
N. Z.
J. Ecol.
Ecol. 11:
old
Z. J.
105-108.
old Nothofagus
11: 105-108.
seedlings. N.
Litchwark,
H.S. 1978.
Insect and
and fungal
defects in red
red and
and
1978. Insect
Litchwark,H.S.
fungal defects
N. Z.
J. For.
For. Sci.
silver
beech. N.
Z. J.
silver beech.
8: 259-266.
Sci. 8:
Mabin,
late Pleistocene
The late
Pleistoceneglacial
M.C.G. 1983.
1983. The
Mabin,M.C.G.
glacial sequence
sequencein
the
valley, southeast
Nelson, New ZeaZeathe middle
middle Maruia
Maruiavalley,
southeast Nelson,
New Zeal.
J. Geol.
26: 85-96.
land.
land.New
Zeal. J.
Geol. Geophys.
85-96.
Geophys.26:
beech (Nothofagus
Manson,
B.R. 1974.
1974.The
Thelife history
silverbeech
Manson,B.R.
(Nothofagus
historyof silver
menziesii).
Proc. N.Z.
N.Z. Ecol.
Ecol. Soc.
21: 27-31.
Soc. 21:
menziesii).Proc.
Lee, T.D.
McClure,
& Lee,
T.D. 1993.
J.W.&
Small-scaledisturbance
disturbancein a
1993. Small-scale
McClure,J.W.
northern
hardwoods forest:
abunnorthernhardwoods
forest: effects
effects on tree
tree species
species abunJ. For.
For. Res.
Res. 23:
dance
dance and
and distribution.
distribution.Can.
23: 1347-1360.
1347-1360.
Can. J.
Milligan,
beech (Nothofagus)
R.H. 1974.
1974. Insects
Insects damaging
damaging beech
(Nothofagus)
Milligan, R.H.
forests.
Proc. N.Z.
N.Z. Ecol.
Ecol. Soc.
forests. Proc.
21: 32-40.
Soc. 21:
1993. Competition
Nambiar, E.K.S.
& Sands,
R. 1993.
for water
waterand
and
E.K.S. &
Sands,R.
Nambiar,
Competitionfor
in forests.
J. For.
Res. 23:
23: 1955-1968.
nutrients
forests. Can.
Can. J.
For. Res.
nutrientsin
1955-1968.
Norton, D.A. 1983.
chronoloModernNew Zealand
Zealandtree-ring
1983. Modern
Norton,
tree-ringchronoloBull. 43:
gies. II.
43: 39-49.
II. Nothofagus
menziesii.Tree-ring
39-49.
Nothofagusmenziesii.
Tree-ringBull.
gies.
Norton, D.A.
J. 1987.
review
D.A. &
& Ogden,
1987. Dendrochronology:
Norton,
Ogden,J.
Dendrochronology:aa review
N.Z. J.
J. Ecol.
Ecol.
with
Zealand applications.
on New Zealand
with emphasis
emphasison
applications.N.Z.
10:
10: 77-95.
77-95.
plant demography
Ogden,
J. 1985.
introductionto
to plant
with
1985. An introduction
Ogden, J.
demographywith
N.Z. J.
special
to New Zealand
Zealandtrees.
trees. N.Z.
Bot. 23:
23:
referenceto
J. Bot.
special reference
751- 772.
772.
Ogden,
J. 1988.
Forest dynamics
and stand-level
stand-level dieback
dieback in
1988. Forest
dynamics and
Ogden, J.
Nothofagus forests.
New Zealand's
Zealand'sNothofagus
forests. GeoJournal17:
GeoJournal 17: 225230.
Ogden,
R.A., Pilkington,
S. &
& Serra,
R.G. 1991.
1991.
J., Fordham,
Fordham,R.A.,
Serra,R.G.
Pilkington,S.
Ogden,J.,
an altitudinal
Forest
gap formation
and closure
formation and
closure along
altitudinal
Forest gap
along an
J. Veg.
Veg.
gradient in
National Park,
Zealand. J.
in Tongariro
Park,New Zealand.
TongariroNational
gradient
Sci.
2: 165-172.
165-172.
Sci. 2:
1996. Ecology
Ogden,
& AlIen,
R.B. 1996.
G.H., &
Allen, R.B.
J., Stewart,
Stewart,G.H.,
Ogden,J.,
Ecology of New
Nothofagus forests.
Zealand Nothofagus
R.S. &
forests. In:
In:Veblen,
&
Zealand
Veblen, T.T.,
T.T., Hill,
Hill, R.S.
Read,
Ecology and
ofNothoJ. (eds.)
The Ecology
and biogeography
NothoRead, J.
(eds.) The
biogeographyof
Hafagus forests,
forests, pp.
pp. 25-82. Yale
Yale University
Press, New HaUniversityPress,
fagus
ven,
CT.
ven, CT.
Pacala,
Forest
& Silander,
J.A. 1993.
1993. Forest
S.W., Canham,
Canham,C.D.,
C.D., &
Silander,J.A.
Pacala, S.W.,
I. The
models
by field
measurements: I.
The design
definedby
field measurements:
models defined
design of a
J. For.
For. Res.
Res. 23:
northeastern forest
forest simulator.
simulator.Can.
23: 19801980northeastern
Can. J.
1988.
1988.
Kobe, R.K.
Pacala,
R.K.
J.A. &
& Kobe,
Canham, C.D.,
Silander, J.A.
S.W., Canham,
C.D., Silander,
Pacala, S.W.,
of
resources
north
1994.
growth
as
a
function
in
north
as
function
resources
a
1994. Sapling
Saplinggrowth
J. For.
For. Res.
Res. 24:2172-2183.
24:2172-2183.
temperate
forest. Can.
Can. J.
temperateforest.
Peters,
Nakashizuka, T.
M. &
& Nakashizuka,
T. 1995.
1995.
R., Tanaka,
Tanaka,H.,
H., Shibata,
Shibata,M.
Peters,R.,
Fagus crenata,
Light
andgrowth
shade-tolerantFagus
climateand
crenata,
growthin shade-tolerant
Lightclimate
Acer mono
Ecoscience 2:
and Carpinus
2: 67-74.
Acer
mono and
cordata.Ecoscience
67-74.
Carpinuscordata.
Philipson,
& Philipson,
classificationof
W.R. &
M.N. 1988.
1988. A classification
Philipson, M.N.
Philipson,W.R.
the genus
Nothofagus (Fagaceae).
J. Linn.
Linn. Soc.
the
Soc. 98:
98:
Bot. J.
genus Nothofagus
(Fagaceae).Bot.
27-36.
27-36.
Phipps,
R.L. &
area increment
increment
& Fields,
M.L. 1988.
1988. Basal area
Fields, M.L.
Phipps, R.L.
programs. Tree-Ring
Tree-RingLaboratory,
Laboratory,U.S. Geologic
Geologic Survey,
Survey,
programs.
Reston,
VA.
Reston, VA.
Poorter,
L. &
S.F. 1993.
induction
& Overbauer,
1993. Photosynthetic
Overbauer,S.F.
Poorter,L.
Photosyntheticinduction
responses
tree species
two rainforest
rainforesttree
relationto
to light
light
species in relation
responsesof two
(Berl.) 96:
environment.
environment.Oecologia
96: 193-199.
193-199.
Oecologia (Berl.)
lR. 1985.
Disturbance regimes
Runkle,
in temperate
forest.In:
In:
1985. Disturbance
Runkle,J.R.
regimesin
temperateforest.
446
446
Runkle,
J.R. et
et al.
al.
Runkle, I.R.
S.T.A.&&White,
P.S.(eds.)
Theecology
Pickett,
Pickett,S.T.A.
White,P.S.
(eds.)The
ecologyofnatural
of natural
disturbanceand
and patch
17-33. Academic
Academic
disturbance
patch dynamics,
dynamics,pp.
pp. 17-33.
New York,
NY.
Press,
Press,New
York,NY.
J.R.
1990. Gap
in an
an Ohio
Ohio Acer-Fagus
Runkle,
J.R.
1990.
Runkle,
Gap dynamics
dynamics in
Acer-Fagus
forestand
andspeculations
on the
the geography
of disturbance.
disturbance.
forest
speculationson
geographyof
Can.J.
J. For.
For. Res.
Res. 20:
20: 632-641.
632-641.
Can.
J.R. && Yetter,
T.C. 1987.
1987. Treefalls
Treefalls revisited:
revisited: gap
Runkle,
Runkle, J.R.
Yetter, T.C.
gap
in the
thesouthern
southernAppalachians.
68:417417dynamics
dynamicsin
Appalachians.Ecology
Ecology68:
424.
424.
G.H. &
& Veblen,
T.T. 1995.
1995. Sapling
Runkle,
Runkle, J.R.,
J.R., Stewart,
Stewart,G.H.
Veblen, T.T.
Sapling
diametergrowth
in gaps
for two
two N
in
othofagus species
diameter
growth in
gaps for
Nothofagus
species in
New Zealand.
Zealand.Ecology
76: 2107-2117.
2107-2117.
New
Ecology 76:
G.H. 1986.
1986. Forest
Forest dynamics
and disturbance
in aa
disturbancein
Stewart,
Stewart,G.H.
dynamics and
New Zealand.
Zealand.Vegetatio
beech/hardwood
forest,
beech/hardwood
forest,Fiordland,
Fiordland,New
Vegetatio
68: 115-126.
115-126.
68:
G.H. &
& Burrows,
L.E. 1994.
1994.Coarse
Coarsewoody
in
debrisin
Stewart,
Stewart,G.H.
Burrows,L.E.
woody debris
old- growth
beech (Nothofagus)
forestsof New
New
oldgrowthtemperate
temperatebeech
(Nothofagus)forests
Zealand.Can.
Can.J.
J. For.
For. Res.
Res. 24:
24: 1989-1996.
1989-1996.
Zealand.
G.H. &
& Rose,
A.B. 1990.
1990. The
The significance
life
Stewart,
Stewart,G.H.
Rose, A.B.
significance of life
in the
the developmental
mixed
of
mixed
history
history
history strategies
strategiesin
developmentalhistory
beech
beech (Nothofagus)
New Zealand.
Zealand.Vegetatio
87:
forests,New
(Nothofagus)forests,
Vegetatio87:
101-114.
101-114.
Stewart,
Stewart,G.H.,
G.H., Basher,
Basher, L.R.,
L.R., Burrows,
Burrows,L.E.,
L.E., Runkle,
Runkle, J.R.,
J.R.,
Hall,
R.J.1993.
1993.Beech-hardwood
Beech-hardwoodforforHall,G.M.J.,
G.M.J.,&&Jackson,
Jackson,R.J.
est
est composition,
andsoil
soil relationships,
North
landforms,and
composition,landforms,
relationships,North
Westland,
New Zealand.
Zealand.Vegetatio
106: 111-125.
111-125.
Westland,New
Vegetatio106:
Stewart,
A.B. && Veblen,
T.T. 1991.
1991.Forest
ForestdeveldevelStewart,G.H.,
G.H.,Rose,
Rose, A.B.
Veblen,T.T.
opment
incanopy
in old-growth
beech(Nothofagus)
opmentin
canopygaps
gapsin
old-growthbeech
(Nothofagus)
forests,
New Zealand.
Zealand.J.
J. Veg.
Sci. 2:
2: 679-690.
679-690.
forests,New
Veg.Sci.
Veblen,
T.T. 1992.
1992. Regeneration
In: GlennGlennVeblen, T.T.
Regeneration dynamics.
dynamics. In:
Lewin,A.C.,
R.K. &
& Veblen,
T.T. (eds.)
Plant SucSucLewin,A.C.,Peet,
Peet, R.K.
Veblen, T.T.
(eds.) Plant
cession:
cession: Theory
and Predictions,
152-187. Chapman
Predictions,pp.
Theoryand
pp. 152-187.
Chapman
and
andHall,
London.
Hall, London.
Wardle,
1984.The
TheNew
New Zealand
ZealandBeeches:
Beeches:Ecology,
UtilisaWardle,J.J. 1984.
Ecology, Utilisation
tion and
and Management.
Zealand Forest
Forest Service,
Service,
Management. New Zealand
Christchurch.
Christchurch.
Wilson,
J.B. &
& AlIen,
R.B. 1990.
1990. Deterministic
Deterministicversus
versus indiindiWilson, J.B.
Allen, R.B.
vidualistic
vidualisticcommunity
structure:aa test
test from
from invasion
invasion by
communitystructure:
by
Nothofagus
menziesii in
in southern
southernNew
New Zealand.
Zealand.J.
J. Veg.
Nothofagus menziesii
Veg.
Sci.
1:467-474.
Sci. 1:
467-474.
Received
Received 29
29 April
1996;
April 1996;
Revision
Revision received
received 5 February
1997;
February1997;
Accepted
11 February
1997.
Accepted 11
February1997.