UC IPM Online UC ANR home page UC IPM home page


SKIP navigation


How to Manage Pests

UC Pest Management Guidelines

Floriculture flower crops.

Floriculture and Ornamental Nurseries

Special Weed Problems for Field-grown Trees and Shrubs

(Reviewed 3/09, updated 3/09)

In this Guideline: More about weeds in floriculture and ornamental nurseries:

LITTLE MALLOW (Cheeseweed). Cheeseweed is a winter annual or biennial plant that forms hard seeds, which can remain dormant for long periods of time. It generally germinates in fall after rainfall or an irrigation but may germinate any time during winter and spring. The seed is not controlled with methyl bromide but most preemergent herbicides, especially oxyfluorfen and oxadiazon, are effective. Oxyfluorfen is also effective applied postemergence to the young plant. Glyphosate is not very effective against this weed.

YELLOW NUTSEDGE. Yellow nutsedge, sometimes call nutgrass, is a perennial sedge that is often confused with a grass. Fumigation before planting is very effective in controlling this weed. Repeat applications of glyphosate (before five-leaf stage when new tubers are formed) will reduce populations over time. If the area is left fallow, halosulfuron can be used and then the crop can be planted the next season. Most preemergent herbicides do not control nutsedge, but metolachlor (Pennant) will suppress the sprouting of the tubers. Soil solarization will reduce yellow nutsedge but will not eradicate it.

BURCLOVER. Burclover is a winter annual that can be a problem if herbicides are not used. Though it is relatively low growing, it is difficult to keep off of the trees and shrubs. Most preemergent herbicides other than those in the dinitroaniline family (e.g., oryzalin, prodiamine, trifluralin) will control burclover.



[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Floriculture and Ornamental Nurseries
UC ANR Publication 3392
C. A. Wilen, UC IPM Program, UC Cooperative Extension, San Diego County
Acknowledgment for contributions to Weeds:
C. L. Elmore, Vegetable Crops/Weed Science, UC Davis

Top of page

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2019 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   Contact webmaster.