Carrot
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
>
Leaves turn yellow
Aster Yellows
>
Plants disappear all or in part
Deer
>
Leaves riddled with shot holes; plant weakens
Flea Beetles
>
Carrot has tunnels
Larvae of Carrot Rust Flies
>
Yellow/whitish spots on leaves; girdled of roots; water-soaked spots/lesions on roots
Leaf Blight (bacterial)
>
Foliage yellowed or white mottling, glaze of honeydew; plant weakens
Leafhoppers
>
Carrot roots are split; hairy or tough
Moisture Problems
>
Carrot covered with hairy roots
Over Fertilized
>
Roots twisted around each other
Overcrowding
>
Carrots are defoliated
Parsleyworms
>
Plants disappear all or in part
Pocket Gophers
>
Leaves coated with white powder
Powdery Mildew
>
Plants disappear all or in part
Rabbits
>
Plant stunted, leaves yellowed, lesions on roots
Root Knot Nematodes
>
Seedlings fail to appear or develop forked shape
Soil Problems
>
Leaves streaked with gray or brown
Thrips
>
Tops of roots turn green
Too Much Sun
>
Carrots are defoliated
Weevils
>
Plant wilts, underground stems/roots chewed
Wireworms
>
Plants disappear all or in part
Woodchucks
>