|
|
Tar
spot - Rhytisma vitis
Annemiek
Schilder, MSU Plant Pathology |
| Home > Scouting guide> tar spot |
| Tar spot is a minor
disease that occurs mostly on wild grapevines. This fungal disease is characterized
by black, slightly raised spots about 1/10 to 1/5 inch (2 to 4 mm) in diameter.
A spot may be surrounded by a circular brown halo up to 2/5 inch (1 cm)
in diameter. The fungus overwinters in these spots. In the spring, they
release airborne spores, which infect the new leaves. |
|
| Additional information
|
|
