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Monday - May 26, 2008

From: Lakeland, FL
Region: Southeast
Topic: Pests, Herbs/Forbs
Title: Asclepias with whitish discoloration
Answered by: Barbara Medford

QUESTION:

I have red/scarlett milkweed planted in my yard. The leaves have a whitish discoloration on the top of some of the leaves and it is spreading. What is it? What do I do about it?

ANSWER:

We first wanted to establish what a red/scarlet milkweed is, and found these two species of Asclepias in our Native Plant Database. Both are native to North America and Florida and, therefore, fall into our field of interests at the Lady Bird Johnson Wildflower Center.

Asclepias lanceolata (fewflower milkweed)

Asclepias tuberosa (butterfly milkweed)

It's possible you have a cultivar, or cultivated variety, of hybridized milkweeds, but they would probably be prone to the same pests and diseases. So, next, since no immediate answer to your question springs to our mind, we need to go looking for what might be causing the discoloration. We will find websites with pictures of some of the possibilities, and you can compare them with your plants. Then, if you find what you think is the pest involved, the website should have suggested treatments.

Minnesota Department of Agriculture, Mealybugs. These are tiny white fluffy insects.

University of Florida Extension, Scale Insects and Mealybugs on Ornamental Plants.

University of California Integrated Pest Management, Pests in Gardens and Landscapes - Aphids.

Colorado State University Extension, Spider Mites.

University of Minnesota Extension, Southern Blight - Sclerotium rolfsii

Generally, Asclepias species are considered fairly pest-free. If none of the above possibilities seem to match the symptoms on your plants, contact the University of Florida Polk County Extension Office - Lawn and Garden. They should have more localized information on newly discovered pests and the control for them.


Asclepias lanceolata

Asclepias lanceolata

Asclepias tuberosa

Asclepias tuberosa

 

 

 

 

 

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