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Tumbleweeds
Nature Bulletin No. 281-A November 4, 1967
Forest Preserve District of Cook County
Richard B. Ogilvie, President
Roland F. Eisenbeis, Supt. of Conservation
TUMBLEWEEDS
In the west, from Texas to Canada, on the grasslands and in dry-farming
regions, a strong wind may roar continuously in one direction, day after
day. When this occurs in autumn, a stranger is fascinated by the
spectacle of thousands of strange objects rolling and bouncing along the
ground or sailing through the air like soap bubbles. When ever they
come to a fence, they pile up against it in a windrow until later arrivals
can roll up over them and bumble blithely onward. When examined,
each i8 found to be a globe of many leafless branches spreading from a
short central stub. That is a Tumbleweed.
Weeds are plants out of place: which persist in growing where we
prefer other plants to be. Most of them produce large numbers of seeds.
Most of them are good travelers --seeds are so adapted that they can be
scattered by the wind. Mushrooms and ferns produce minute dust-like
spores. The maples, elms, ashes and other trees have winged seeds. The
cottonwood' s tiny seeds, each attached to a fluff of down, float away
like summer snow. The seeds of dandelions, milkweeds and thistles,
supported by parachutes of fine hairs, are blown far and wide by the
slightest breeze. But a tumbleweed, when mature, breaks away from its
root and the whole plant goes tumbling over the fields and prairies,
scattering seeds as it goes.
There are five species of tumbleweeds in the United States. The
Common Tumbleweed, a member of the Amaranth Family, is native
and most abundant in the arid regions from Canada to Mexico. It has
spread along the railroads to eastern states where it is found on railroad
embankments, roadsides, gravel pits and waste places -- particularly on
dry sandy soils. It is a bushy plant, from 6 inches to 2 feet tall, with
many whitish branches and small pale-green leaves. In autumn it sheds
its leaves, breaks off at the ground surface, and is blown away --
sometimes for miles -- scattering its thousands or hundreds of thousands
of black seeds.
The Tumbling Mustard was brought here from Europe and spread
rapidly over Canada and our northern states. It is a tall many-branched
plant with deeply-cut leaves, It may bear a million or more seeds in its
long slender pods. When mature, the whole plant breaks off but,
because the pods are tough, it may blow about the prairie all winter,
dropping a few seeds here and there. These seeds give ground-up grain
a bad flavor.
The worst of the tumbleweeds is the Russian Thistle, a native of Asia,
which is not a thistle but a member of the Goosefoot Family. Its
branching stems form a loose globe sometimes 4 feet in diameter. Its
long thin spine-tipped leaves and spiny bracts give it a bristly
appearance When young and green, it can be eaten by cattle but when
mature it is like cactus. It thrives on land too dry for most plants and is
the last survivor in drought years. In the sand dune country around
Gary, Indiana, it has a brilliant reddish color in autumn.
There are two other tumbleweeds, both native members of the
Goosefoot Family: the Bugseed and the Winged Pigweed. These have
spread over much of the United States and Canada on sandy or alkali
soils and the latter also has brilliant-reddish tints in autumn. There is,
too, a native grass very common in the eastern and north central states,
called Old Witch Grass, Tickle Grass or Fool Hay. It has a large loose
spray of flowering stems which when the seeds are ripe, break loose and
travels like a tumbleweed. If a mat of these, plastered against a fence, is
ignited, it burns -- pouf! -- like gunpowder.
Some weeds at least protect the soil, but tumbleweeds are useless
weeds.
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Update: June 2012
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