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
Use the late-spring weed survey
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
(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.
(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.
(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
| 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
(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.