Pests And Weeds

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A close-up of a California burclover plant showing deep green compound leaves with 3 leaflets, small yellow flowers, and green, round, spiny seeds.

Shamrocks, Clovers, or Weeds?

March 18, 2026
By Lindsey Hack
St. Patrick’s Day makes us think about shamrocks and all things green. With recent warm weather following winter rains, your lawn or garden might be dressing up for Saint Patrick’s Day and Spring with clovers and other weeds.  Clovers begin to germinate in the fall and continue throughout winter…
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Person wearing gloves pouring liquid from a measuring cup into a spray bottle on cement.

Upcoming Webinars from UC IPM

February 9, 2026
By Yulie Velez
If you missed our first Urban & Community IPM webinar of the year, Pests of Backyard Chickens, don’t fret, we have more for you! Join us every third Thursday of the month from 12:00pm to 1:00pm PT to learn about a wide range of urban pest management topics. This series is free and open to the…
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Several large, brilliant purple flowers scattered over dense, deep green leaves.

When Ornamentals Escape

January 20, 2026
By Cherie Shook
You might be surprised to learn that a few of your favorite ornamental plants are invasive to California and can “escape” your yard causing big problems in the wild. When plants escape landscape and garden boundaries, it is often due to seed distribution or aggressive roots. An invasive plant species can…
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UC Master Gardeners of Placer County: Article

Stopping Crabgrass Before It Starts

December 18, 2025
By Gay Wilhelm and Trish Grenfell, UC Master Gardeners of Placer County Q: What can I do to stop crab grass in my lawn? A: Who hasn’t done combat with crabgrass? But there is help and NOW is the time to take action. Using a pre-emergent herbicide in mid to late February will help…
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Tall, green stalks of giant reed towering over two humans standing in front.

Keep Invasive Plants Out!

June 11, 2025
By Lindsey Hack
The golden flowers of French broom covering hillsides and the tall, striking stalks of pampasgrass stand out on trails and roadsides. These plants may be beautiful, but they are invasive and harm California’s natural landscapes.  Invasive plants outcompete and crowd out native plants, damaging…
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Bermuda buttercup infesting a bed of landscaped plants.

Spring is in the Air, and Oxalis is Everywhere

April 17, 2025
By Lindsey Hack
Bermuda buttercup (Oxalis pes-caprae), also called buttercup oxalis or sourgrass, might be a familiar sight in winter and spring, particularly to those who live in coastal regions or the Sacramento Valley. Some people enjoy seeing this plant’s cheerful yellow flowers pop up in their spring gardens, but for…
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Master Gardener Information Desk for home gardener advice
UC Master Gardener Program of Sonoma County: Page

Information Desk

Get free expert help with garden problems and advice from the UC Master Gardener Program of Sonoma County Information Desk supported by research-based information from the University of California and other academic or government institutions.
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