Otto Luyken Laurel pests and diseases - Ask Extension
My Otto Luyken Laurel seems to be having numerous issues or maybe just one. I am uncertain how to identify and/or SPECIFICALLY treat the problem(s)....
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Otto Luyken Laurel pests and diseases #267277
Asked August 03, 2015, 5:13 PM EDT
My Otto Luyken Laurel seems to be having numerous issues or maybe just one. I am uncertain how to identify and/or SPECIFICALLY treat the problem(s).
We have had an awful summer in Northern Virginia of hot temperatures, high moisture and humidity. As a side note, my Virginia soil is very compact clay even though the soil was treated with composting materials when we planted the Otto Luyken shrubs. Additionally, these Otto Luyken are located on a bit of a hill to increase drainage. I do have many beetles and slugs that have been eating other plants in my yard. Also, my Ajuga and Lilly of the Valley seem to be having fungus issues which seem to be brought on by the extended excessive heat and humidity problems this summer.
Some of the enclosed pictures of the leaves indicate shot hole borers (Scolytus rugulosus) since the holes are perfect circles. However, I don't see oozing gummy sap and other leaves look like they have been eaten by beetles (less perfect and eaten from the edges inward). I am not sure if I should be concerned with the leaves with perfect circular holes and the other leaves that are being eaten by some hungry insect. Other leaves have brown spots.
The most notable feature and my main concern is the white substance completely covering most of the lower branches at one of my Otto Luyken shrub's base. This particular shrub, with the powder on the base branches, is in a more shady location (part shade/sun) than some of the other Otto Luyken shrubs. The white substance is a bit chalky when I wipe it off with my finger. I can't tell if it is root rot or powdery mildew. There is not an indication of the white substance on the leaf surfaces of any of my Otto Luyken shrubs which is usually an indication of a powdery mildew problem. However, my Ajuga, Lilly of the Valley, Dogwood and Bee Balm indicate fungus going on in the yard due to all the humidity.
I do have a large planting of Otto Luyken in the yard. Is there a way to treat this particular plant with the white substance on the lower branches (what specific type of product and application)? Do I need to be concerned with this plant infecting my other Otto Luyken plants requiring me to destroy the plant? Is the problem powdery mildew even though I don't see that on the leaf surfaces? Should I be concerned with the holes and brown spots on the leaves that are found in many of the other Otto Luyken plants?
Thanks for your time and consideration.
We have had an awful summer in Northern Virginia of hot temperatures, high moisture and humidity. As a side note, my Virginia soil is very compact clay even though the soil was treated with composting materials when we planted the Otto Luyken shrubs. Additionally, these Otto Luyken are located on a bit of a hill to increase drainage. I do have many beetles and slugs that have been eating other plants in my yard. Also, my Ajuga and Lilly of the Valley seem to be having fungus issues which seem to be brought on by the extended excessive heat and humidity problems this summer.
Some of the enclosed pictures of the leaves indicate shot hole borers (Scolytus rugulosus) since the holes are perfect circles. However, I don't see oozing gummy sap and other leaves look like they have been eaten by beetles (less perfect and eaten from the edges inward). I am not sure if I should be concerned with the leaves with perfect circular holes and the other leaves that are being eaten by some hungry insect. Other leaves have brown spots.
The most notable feature and my main concern is the white substance completely covering most of the lower branches at one of my Otto Luyken shrub's base. This particular shrub, with the powder on the base branches, is in a more shady location (part shade/sun) than some of the other Otto Luyken shrubs. The white substance is a bit chalky when I wipe it off with my finger. I can't tell if it is root rot or powdery mildew. There is not an indication of the white substance on the leaf surfaces of any of my Otto Luyken shrubs which is usually an indication of a powdery mildew problem. However, my Ajuga, Lilly of the Valley, Dogwood and Bee Balm indicate fungus going on in the yard due to all the humidity.
I do have a large planting of Otto Luyken in the yard. Is there a way to treat this particular plant with the white substance on the lower branches (what specific type of product and application)? Do I need to be concerned with this plant infecting my other Otto Luyken plants requiring me to destroy the plant? Is the problem powdery mildew even though I don't see that on the leaf surfaces? Should I be concerned with the holes and brown spots on the leaves that are found in many of the other Otto Luyken plants?
Thanks for your time and consideration.
Fairfax County Virginia
Expert Response
It looks like you have a few things going on here and need a closer look a the white substance. We
have Plant Clinics at different times, around the County
thru September where you can bring a sample for diagnosis and samples
can also be submitted to our Diagnostic Laboratory. The below link will
take you to the list of Plant Clinics and their times and locations.
Bring a sample 10-12 inches long showing both
the healthy and diseased portions on the same branch. Pictures are
helpful but not a substitute for plant or insect samples.
Many
times accurate ID of specific plant samples becomes difficult
due to incomplete information, or poor samples. Samples should be
FRESH, and consist of leaves, twigs, branches. Include flowers, seeds
and fruit or berries if available. Samples should be in a Plastic Bag,
do not use paper bags or envelopes. Bring a large
sampling of the specimen to be ID’ed.
At
the Plant Clinic you will need to fill out a lab submission form, good
photographs are welcome to accompany your live sample. Photos are not a
substitute for live fresh samples.
Link to Plant Clinic Locations: http://fairfaxgardening.org/plant-clinics/2015-plant-clinic-schedule/
Link to Plant Clinic Locations: http://fairfaxgardening.org/plant-clinics/2015-plant-clinic-schedule/
I went to the 10th floor of the Pennino Building today, August 10, 2015, and submitted my samples which I cut out of the shrubs this morning. I did not have a way to print pictures to include with my submission. Is there an email address where I can share the pictures of the location of the plants in question to supplement the samples I brought in today?
Many Thanks!
Many Thanks!
