Keep records of pests you see to help choose a seedling
variety for next year’s alfalfa planting and to implement
proper equipment sanitation. Names link to more information on
identification and management.
Click on photos to enlarge
Damping off diseases Identification tip: Roots and leaves rot due to seedling diseases (damping
off).
Downy mildew Identification tip: Spots on upper sides of infected leaves are gray-green
to tan.
Sclerotinia rot Identification tip: Hard black sclerotia resting bodies form on the mat
of white mycelium.
Stem nematode
Identification tip: Plants infected with stem nematodes have dead stem buds,
stunted shoots, and swollen internodes.
Cutworms Identification tip: Caterpillars
are about 1.5 to 2 inches long and appear smooth-skinned
with various colors and patterns. Larvae frequently roll
into a C shape when disturbed.
Aphids Identification tip:
Four aphids commonly cause damage in alfalfa hay. To
identify cowpea aphid, pea aphid, blue alfalfa aphid
and spotted alfalfa aphid, see “Identifying
aphids”.
