|Dr. Chuck Hodges at age 82.99.|
One branch was remarkable in that it had not one but two Gymnosporangium rusts, indicated by the arrows in the photograph below.
|Infections of quince rust (left) and cedar-apple rust (right) on the same eastern redcedar branch.|
The large woody galls on the right are produced by cedar-apple rust (Gymnosporangium juniperi-virginianae), which will be exuding gelatinous orange telial horns when the warm rains arrive in April or May. The spores produced on those horns (basidiospores from teliospores, if you want to get technical) will blow on the wind and infect the leaves and fruit of nearby apple and crabapple trees. Those infections will result in the production of another kind of spore which - if fortunate enough to get a ride on the wind to a juniper - will cause a new infection in summer. Eastern redcedar and Rocky mountain junper are the principal hosts. Those infections will not develop into galls until the year, and they'll mature the following spring. For more information and some nice pictures, see last year's blog post on this disease.
|Quince rust infection on an eastern redcedar branch.|
|The quince rust fungus, Gymnosporangium clavipes under the microscope.|
The two-celled orange teliospores are only 1/500 of an inch long.
Carrot-shaped pedicels beneath are diagnostic for the species.
|Ornamental pear fruits covered with the white papery peridia of the aecia of quince rust.|
Shed spores from the fruit give an orange cast to the leaves. Note: This stage is still months away.
|Symptoms of Kabatina tip blight on juniper.|