UC IPM Online UC ANR home page UC IPM home page


SKIP navigation



Perennial Weeds You May See

Perennial weeds are continually a problem in almond orchards and management practices should be geared to preventing their establishment in the rows or row middles of the orchard. Below are some of the common perennials in California almond orchards.

Use the late-spring weed survey form (99 KB, PDF) to record your weed observations in order to make weed management decisions. Keep these records so that you can track weed population information from year to year to better understand ongoing weed control problems such as resistance.

Names link to more information on identification and biology.

Click on photos to enlarge
Seedling of burmudagrass
(Cynodon dactylon): Grass family; perennial; first leaves with somewhat rough surface; ligule surrounded by ring of hairs with tuft of long hairs on either side; auricles absent; stem flat, wiry, and without hairs.
Johnsongrass rhizomes.
(Sorghum halepense): Grass family; perennial; persists and spreads via underground stems (rhizomes), which are thick, fleshy, and segmented; roots and shoots can rise from each rhizome segment; leaves have a prominent whitish midvein.
Dallisgrass leaf sheath of the seedling.
(Paspalum dilatatum): Grass family; perennial; first leaves rolled in bud; ligule membranous and tall, with bluntly pointed or rounded tip; long, silky hairs at collar; no auricles; sheaths flattened with prominent midrib; first leaf sheaths softly hairy.
No photo available.
(Cyperus spp.): Sedge family; perennial; first leaves inconspicuous and grasslike; grow mainly from tubers or "nutlets" formed on rhizomes, mostly in upper foot of soil; in cross section, leaves V-shaped, arranged in sets of three at base, and stems triangular.
Seedling of white sweetclover, Melilotus alba, at the four-leaf stage.
White clovers
(Trifolium spp.): Pea family; perennial; seed leaves spatulate, smooth; blades taper into petiole; first leaf simple, truncated at base, round to broadly oval; later leaves with 3 leaflets per leaf, smooth, alternate, lower surface gray green, upper surface green; usually light green splotch near base of each leaflet.

PDF: To display a PDF document, you may need to use a PDF reader.

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2016 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   /PMG/C003/m003bppernlweeds.html revised: June 24, 2016. Contact webmaster.