UC Master Gardener Program of Alameda County

Bugs and Insects

Learn about the good insects and the pesky insects. Manage common problems encountered in Alameda county in both the vegetable garden and landscape/ornamental environment. Learn to spot invasives and how to manage them.

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aphids live and mummified on gardenia bud with parasitoid wasp
Over the Fence (Alameda County): Article

How Climate Change Is Affecting Insects and Practical Tips for Gardeners

May 3, 2026
By Judy Quan
Climate Change and Weather in the Bay Area   March 2026 was one of the driest and warmest Marches in recorded history in the Bay Area. The March heat wave pushed temperatures across much of the West 3 to 9 degrees Fahrenheit above average, according to the Climate Prediction Center. In the…
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Over the Fence (Alameda County): Article

Aedes aegypti: A Dangerous Mosquito in Alameda County

March 26, 2026
By Mireille Giovanola
Introduction   Mosquitoes are not just pesky biters that may cause allergic reactions; they can be vectors (that is, they transmit parasites) for worrisome diseases that may cause severe health problems and even death. Mosquito-borne diseases caused by protozoa (very small, single-celled organisms…
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Crape Myrtle leaves with sooty mold
Over the Fence (Alameda County): Article

What is that Black Stuff on my Plant Leaves?

June 14, 2025
By Judy Quan
The black stuff on your leaves is likely sooty moldThe black stuff on your leaves is probably sooty mold, a fungal disease growing on plants and other surfaces, and it is often seen in the spring and summer. The leaves or stems have a black coating that looks like soot. If you look closely, it is growing…
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UC Master Gardener Program of Alameda County: Page

Citrus Leafminer

Understanding citrus leafminer: Learn why this common pest causes cosmetic damage but doesn't harm your citrus trees.
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