Disease on skip laurel

Asked June 7, 2018, 9:34 AM EDT

We have several issues with the first and most severe problem being the leyland cypress trees which were planted eight years ago and had not exhibited any problems prior to last fall when the lower branches began turning brown. This spring the browning is very pronounced and has moved halfway up the trees. The other problems are with the newly planted skip laurels and nearby ground cover. The laurels all have some amount of damage which appeared just recently and is distinguished by dieback and leaf holes and the surrounding ground cover is also dotted with holes We so appreciate any diagnostic information and treatment guidance.

Montgomery County Maryland disease issues shrubs abiotic issues trees groundcover

1 Response

Leyland Cypress and other evergreens had a pretty rough winter. We have seen a good deal of browning and dieback.
Additionally, Lelands often do well for a time here (usually more like 20 years) but then start to suffer from stress (they are not ideally suited to our climate), drought and then get canker diseases.
Unfortunately, most evergreens cannot grow back from brown wood so yours looks like it may need to come out.

This problem is not related to what you are seeing on your violet groundcover, or your Laurel, and they are not related to each other either.
Something is munching on your violets- could be slugs or caterpillars, but it won't hurt them. They are tough native plants.
The holes in the leaves of your Laurel could be a common leaf spot disease called Shothole fungus. It begins as a lesion on the leaf (you can see one on an old leaf) but then as it dries, the circle drops out leaving a hole. There is nothing to do for it, and it doesn't look bad.
The discolored looking leaves and stems look more concerning. We would clean all that dead and dying stuff out to increase the airflow. (Throw it away, don't compost diseased material).
They do not like to be water-logged, so it's possible that they are reacting to our wet, wet spring, and also the fact that the airflow around the plant while under the Leyland made conditions ripe for foliar disease. Again, there is nothing you need to do but clean it up and pull mulch and/or Leland leaves from around the base of the plant- it shouldn't touch the trunk.

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