Hydrangea Leaf Tier

May 14, 2012 | C.L. Fornari | Problem Solving, Shrubs

Do you grow white flowering Hydrangeas? If your plants are Annabelle, Incrediball or other form of Hydrangea arborescens you might want to take a close look at the leaves. (Some people have also reported this pest on climbing hydrangeas.) In May there is a sneaky larvae at work that is called a “leaf tier.” This little worm, Olethreutes ferriferana, ties leaves together to form a protective little pocket. Once hidden in this way it proceeds to eat the foliage and developing flower buds.

If you see tied leaves such as the one pictured below, clip them off and throw them in the garbage. You can spray the shrub with spinosad (we have Captain Jack’s Dead Bug Brew) to kill other larvae that may hatch and try to do the same thing. Once inside tied leaves, however, the spinosad won’t be effective, so remove these immediately if the look of these leaves bother you. Fortunately, the plants will still have time to make new flowers on these stems.

If you open those leaf packets you’ll find the larva inside. Because it is protected inside the leaves, no spray will kill it.

Here is how the leaf tier looks when the leaves are bound together. The larva has knitted the two leaves together so that they don’t open up.

If you look closely at this leaf you’ll see the larva that is responsible. It’s in the center, along the main rib of the leaf, and it has a tiny black head.

Posted in Problem Solving, Shrubs

7 Comments

Nancy on May 20, 2019 at 9:18 pm

Is there a way to prevent this?

Reply
- CLFornari on May 20, 2019 at 10:30 pm
  
  Nancy,
  Prevent? No. Control? Yes. Pinch off the affected leaves and throw out,but not in the compost.
  
  Reply
Cheryl Ronan on June 5, 2019 at 12:43 am

What is spinous ad?

Reply
- CLFornari on June 5, 2019 at 1:22 am
  
  Spinosad is a bacteria similar to Bt that kills larvae.
  
  Reply
Holly on October 19, 2022 at 11:49 pm

I have these on my Annabelles and they do very little damage. They are native and part of the ecosystem so I leave them alone. Birds feed the caterpillars to their young, and if not they mature into the leaf tier moths. Spiders also shelter in their folded leaf structures. No need to kill them.

Reply
L Gainer on May 25, 2023 at 6:08 pm

Do they affect the hydrangea blooms?

Reply
- CLFornari on May 26, 2023 at 10:41 am
  
  Since the flowers are at the ends of the branches, and these are eating those ends, yes, flowering is affected.
  
  Reply