Ecology of Red Maple Swamps in the Glaciated Northeast: A ...

2.0
1 .o
Curtis
Corner
Shermantown
2.0 Mink Brook
1.0
yrwa wtlrrl nwm waim levels approach the longtern1
site. average, Water levels in X&e Champlain
wc>rc, coraside~-ed to be MrIll~l &on1 1957 to 19fi8,
but ~bnornznlly high fi-om ~969 to 1976 (Vosburgh
19';y). Trw growth was greater during the period
of I ~O~IX~R~ water levels (Table 5.1), and variations
ill over tlrl~t time irlkrval were most
strongly corrclatsci with tree or stand characteristics.
Xhzring years of ~bxlomrilly high water
lclst\ls, tsc~
growth was lnost strongly influenced by
hyilr-oloby. At five of the six Rhode Island swamps
strldii~tl by Lawry (I9%4)> greatest gr~witl occurred
during years when the average annual (April-Decemhcr)
water level was dosest t;o the 6-year mean
(Fig. 5.2). E;vidertly, the trees were well adapted to
t hc nverizgr wakr level conditiorls at the individual
sit~ss, r a ~ d del~iu-t~uws from those average co~xditicrns,
t-ither rxti~rkcdly wet&?r or drier, resulted in
diminished growth. Site-specific adaptation by
trtws also may explain why the between-year
growth trends shown in Fig. 5.1 were similar at the
vitrivi~s sibs, eve11 though average water levels
diff~~rrd sigrlificantly among sites in most years.
In a study of artificial permanent flooding in
'I'cnnc.,gsr>c, f la11 and Smith (1955) found that red
niaplrs remained healthy if the root crowns were
flocded for less than 37% of the growing season;
flooding for more than 41% of khe growing season
resulted in the death of all trees within a few
yrtirs. Studies in the glaciat~d Northeast generizlly
support these findings. Red maple growth in
L4akrl Cf~axrxpI~~ir~ swarnps declined when root
c.roupns were sulmergtd far more than 5@/0 of the
gnrowirlg season, on the avorage (Vosburgh 1979).
Year
Fig. 6.1. Annual rad~al growth of red maple in six Itkiode
Island swamps from 1976 tkrrough 1981 (after I~wry
1984). Data are based om 30 trees per sita, two
Increxnent cores per tree.
ations in growth were also pronounced ('Vosburgl~
1979). Generally, variation was least on the lowest
snd vtettesk sites; tmes 0x2 siightly more elevated
sites with shorter hydroperiods showed more
growth respor~e to annual hydrologic variations.
Research at Lake Champlain and in mode ISland
suggests that tree grott.th is greatest in those
'I'able 5.1. r%r~nuul radial growth of red maple trees
in relation to surfwx-water hydroperiod in 10
I~zkc. Clmmplain wet lcrrzcls bet ween 1957 and
1976. Values inparent/@scs are ranges ofannual
rtir eans (from Vosburgh 1979).
Mean seasonal
duration of Percentage of
Mrarl annual flaodi~rg, growing
o Mn y -September season