IS this a blight? - Ask Extension
My rabbit brush and desert sweet plants are dying off. I'll enclose pics. These otherwise thriving plants are turning brown and dying. I've removed...
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IS this a blight? #879196
Asked July 29, 2024, 10:05 AM EDT
My rabbit brush and desert sweet plants are dying off. I'll enclose pics. These otherwise thriving plants are turning brown and dying. I've removed infected plants, and wonder if I should sterilize my tools (if so, with what).
What can be done to eliminate whatever is causing this die off?
Crook County Oregon
Expert Response
Thank you for your question.
These shrubs are very drought resistant once they are established. If they are relatively new, their roots may not have been extensive enough to support the plant during the dry summer. You may already have this, but here is a link to a helpful Oregon State Extension publication "Water-wise Gardening in Central Oregon" - https://extension.oregonstate.edu/catalog/pub/em-9136-water-wise-gardening-central-oregon
Leaf blight usually only occurs when the weather is warm and humid. You have done the right thing when you removed effected plant material. The only way to know if this damage is caused by leaf blight would be to submit a plant sample for lab analysis. The Oregon State University Plant Clinic performs this service (for a fee) - https://bpp.oregonstate.edu/plant-clinic/submit-sample/services-and-fees
Sterilize your tools with a 10% bleach/water solution (1 part bleach, 9 parts water). Dip them in and it will immediately work to kill any pathogens.
There is also the possibility that spider mites are causing the damage. Mite populations and their negative effects can explode in hot, dusty conditions. Plants under water stress are also highly susceptible to mite infestation. Here is some information - https://ipm.ucanr.edu/PMG/PESTNOTES/pn7405.html
These shrubs are very drought resistant once they are established. If they are relatively new, their roots may not have been extensive enough to support the plant during the dry summer. You may already have this, but here is a link to a helpful Oregon State Extension publication "Water-wise Gardening in Central Oregon" - https://extension.oregonstate.edu/catalog/pub/em-9136-water-wise-gardening-central-oregon
Leaf blight usually only occurs when the weather is warm and humid. You have done the right thing when you removed effected plant material. The only way to know if this damage is caused by leaf blight would be to submit a plant sample for lab analysis. The Oregon State University Plant Clinic performs this service (for a fee) - https://bpp.oregonstate.edu/plant-clinic/submit-sample/services-and-fees
Sterilize your tools with a 10% bleach/water solution (1 part bleach, 9 parts water). Dip them in and it will immediately work to kill any pathogens.
There is also the possibility that spider mites are causing the damage. Mite populations and their negative effects can explode in hot, dusty conditions. Plants under water stress are also highly susceptible to mite infestation. Here is some information - https://ipm.ucanr.edu/PMG/PESTNOTES/pn7405.html
Thanks for your response. Last Wednesday (7/31) I express shipped one plant, including root, dead plant parts, and live plant parts. I asked them to rush, saying that I was happy to pay their $200 rush fee. As of today, I have hear no response. Should I be concerned?
It reality, I am concerned. Plants in nearly an acre of my landscape are being affected. I have lost several already, and stand to lose many more.
Whatever is killing my plants starts at the base with leaves turning brown. It soon consumes the entire plant. I had hoped that OSU Botany would solve the problem, and be able to tell me how to treat infected plants.
Thanks and please advise,
You should call the OSU Plant Clinic directly to ascertain status of your submittal. Phone <personal data hidden>
