Key identifying traits
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Plants grow nearly flat on the
ground with branches 6-18” long
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Leaves are alternate and prickly
on the lower side of the midrib
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Leaves are opposite and divided
into 3 primary lobes and these divided into secondary lobes
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Flowers are pinkish to pale blue
in long dense spikes and have long leaf like bracts
Biology and ecology
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It can be an annual or short
lived perennial, spreading by seed only
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Commonly see it growing along
roads, driveways and sunny dry areas; also showing up more in
pastures- we are seeing increases in the population of
this plant over the past few years
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Prefers sunny, dry sites that
are sandy, rocky or gravelly
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Prostrate vervain is a native
and widely distributed over North America
Control
Prevention –
Learn to identify plants; start monitoring early in the season
Biological –
No known biological control in our area
Cultural –
Plant competitive grass or other cover crop but tillage can be a
good control
Mechanical –
Height of the plant is too low for mowing to be an effective option
Chemical – the
PNW Weed Management handbook does not have recommendations for
this plant but some mixtures containing 2,4-D, MCPA, and Dicamba
have vervain on their list of controlled species
|
Photo: Mike Haddock,
http://www.lib.ksu.edu/wildflower/ |
