Cedar-apple rust is a common rust disease that impacts trees in our area. This fungal disease, as well as similar fungi like cedar-hawthorn rust and cedar-quince rust, moves from one host to another in order to survive. Cedar-apple rust rarely kills a tree, though if the infection is severe it can damage parts of the tree and impair fruit production. For the most part, this rust is an aesthetic nuisance more than anything. Trees impacted here in Kansas include:

  • Eastern red cedar
  • Hawthorns
  • Junipers
  • Pear trees
  • Apple trees
  • Crab-apple trees

How is it Transferred?

When the warm spring rains hit Kansas, mature galls from cedar trees release fungal spores that are transferred to apple and pear trees by the wind, traveling up to 2-3 miles! Then in the summer months (typically June and July), spores are released from the fruit trees which re-infect the junipers, cedars, and hawthorns.

The Symptoms

In junipers, hawthorns, and cedars, the disease manifests itself in the form of brown, perennial gulls that grow on the twigs. When these gulls are mature, they swell and repeatedly produce orange, gelatinous, telial horns. Symptoms become noticeable in the spring as the rainy season begins.

In apple and pear trees, the symptoms appear as circular, yellow spots on the upper surface of the leaves shortly after they bloom. In late summer, brownish clusters will appear on the underside of the leaf, beneath the spots.

Preventative Measures

As with most things, prevention is the best medicine! The key to preventing cedar-apple rust is to break the cycle. If we were able to control the location of different kinds of trees, we’d keep cedars and junipers far away from pear and apple trees; however, that’s just not realistic. This is where preventative fungicide come into play.

Topeka Landscape team of professionals can treat for Cedar Apple Rust. Reach out to us today for more information on these treatments and learn how we may be able to help protect your trees!