Early Summer Virus Symptoms

Summer has finally arrived in Minnesota. As perennial plants are coming out of dormancy they will often exhibit symptoms of virus infections due to their weak immune system. As the growing season progresses and temperatures climb many virus symptoms will fade as the plant’s immune system kicks into gear and you will not know your plant is hosting a virus.

One common virus symptom to be observed in the spring is the leaf mottling (blotchy discoloration of leaves) and yellow rings caused by Tobacco Rattle Virus (TRV). Once a plant is infected with TRV it will remain infected for the duration of its life. TRV can be spread by nematodes, mechanically (by using virus contaminated tools), and through grafting of plants.

TRV in Dicentra (Bleeding Heart)
TRV in Epimedium (Bishop’s hat)
TRV in Hydrangea

Elm Mosaic Virus is also exhibiting strong symptoms in Elm trees in St. Paul. This virus will show symptoms in the first leaves that the trees send out, and symptoms fade as summer progresses. Elm Mosaic Virus will likely become more visible as many ash trees are being replaced with Dutch Elm resistant trees. Although Elm Mosaic Virus will not immediately kill a tree, over time it will weaken the tree.
Elm Mosaic Virus in Elm

All photos were taken by Sara Bratsch. For non commercial use only.

Please contact regarding all other uses.

Cite this article:

Bratsch, Sara. "Early Summer Virus Symptoms". 20 June 2014. http://plantpathlesstraveled.com/early-summer-virus-symptoms/