The Rural Voice, 1993-08, Page 36WEED OR NOT?
'Mexican Bamboo' is neither Mexican nor bamboo but it is an interesting plant
By M. J. Hayes
BANG. BANG -BANG.
BANG. The disturbance
roused me from a Saturday
morning sleep in early May.
It took me a moment to orient myself;
then, the tang of smoke drifted in
through my open bedroom window.
Bang. Crackle. Snap. At last, I
recognized the sounds and smells of
my neighbour preparing for a new
crop of bamboo to spring into a
hedge along our property lines.
When we moved into this house,
the unusual looking hedge intrigued
me. A friend volunteered a close
guess — bamboo. I could hardly
believe any variety of bamboo could
grow in cottage country in Ontario.
Research proved me wrong. Bamboo
could thrive in these climate
conditions, but one detail did not
match. Bamboo flowers every 12 to
120 years depending on the species;
the plant I knew flowered every year
in late summer or early fall. What
was this plant?
The trail of research led from the
local library to the local conservation
authority, the Ministry of
Agriculture, the
New Liskeard
College of Agricul-
tural Technology,
and to the ultimate
source, the Ontario
Agricultural Col-
lege at the Univer-
sity of Guelph.
Commonly cal-
led Japanese Bam-
boo and Mexican
Bamboo, the peren-
nial is neither from
Mexico nor is it
related to bamboo,
although it does
grow with the speed
of bamboo. In the
botanical world,
this perennial is
actually the plant
known as Polygon -
um cuspidatum Sieb. & Zucc., part of
the buckwheat family, the same
grouping that includes rhubarb,
The plant spreads through a
network of underground rhizomes or
stems. From this network, new
shoots will sprout in early
spring. These young
shoots have been known
to be cooked like aspara-
gus or as a puree. Stems
are hollow between the
joints or nodes — like
bamboo — appear smooth,
round, and are a reddish,
almost purple colour. At
each node, a sheath will
form around the stem.
Called the ochrea, the
clear or light green sheath
is s'milar to a membrane
but does not last long, turning brown
and disin_agratiug with the growth of
the stems. Rapid growth (up to a foot
a day) will continue throughout
spring to late fall. These plants can
grow from three to nine feet tall.
Knotweed leaves develop at each
node, alternating sides of the stem
with each leaf. The foliage is broad,
2-10 cm wide, and ends abruptly at a
tip after a length that varies from 5-
15 cm.
From July to September, the
Japanese knotweed is adorned with
showy, greenish -white flowers in a
cluster formation up to 15 cm long.
The flower cluster develops from the
angles between the stem and the
stalks of the leaves, and is usually
limited to the plant's upper portions.
From these flowers, seeds form that
are triangular, about 7 mm long, and
enclosed in a papery, outer shell.
As the name suggests, the
Japanese knotweed is a weed and it
is difficult to keep its growth in
check. If the rhizomes are cut, the
plant produces more. Manure or
fertilizer should not be applied; the
applications only encourage the
plant's growth. Even more
complicated is eradication of the
plant. It is resistant to most
herbicides, but if the shoots are cut
Some may regard it as a weed but
Japanese knotweed can provide an
attractive privacy screen.
princes -feather, silver lacevine, and
weeds such as smartweeds. The plant
is more commonly called Japanese
fleece -flower or Japanese knot -
weed.
Japanese knotweed originated in
Eastern Asia, and spread to North
America mostly
Spring shoots sprout around cut
off stalks from last year' s growth.
32 THE RURAL VOICE
through deliberate
cultivation. Ontario's
pioneers planted the
perennial to provide a
bushy, hardy founda-
tion planting or as a
screen around the
farm's outhouse. As
these farms fell into
disuse, or were divi-
ded up to allow
cottagers to build, the
plants thrived. To-
day, old buildings,
former building sites,
roadsides, and waste
sites can sprout
Japanese knotweed.
As well, the perennial
can create problems
along fence lines and
in gardens and lawns.