| Agronomy
105's Weed ID |
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Johnsongrass
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| Johnsongrass
is a perennial that spreads both by seed and by rhizomes. Rhizomes,
as you will recall, are underground stems that run parallel to the soil
just below the soil surface. In the past, infestations have been
so bad in some areas that it has caused entire fields or farms to be abandoned.
Originally Johnsongrass, which is a close relative to grain sorghum, was
introduced into the southern part of the United States as a forage crop
and is still used for this purpose in parts of our country. |
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It is
most common on frequently flooded land because the floods wash in new rhizomes.
Herbicides that are effective in controlling Johnsongrass have just become
available over the past 10 years. |
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| The oval-shaped
seed is quite similar to Sudangrass seed. However, Johnsongrass seed
is smaller and will have a knob on the end of its rachilla, whereas in
Sudangrass these knobs are almost always broken off. |
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