Research Report
Coastal Sandbur — a Troublesome Grassy Weed
sandbur is a summer annual grass that, under certain environments, may persist as a short-lived perennial. It has long, narrow leaves (blades up to 8" long and about 1/4" wide, with a short hairy ligule). During summer and early fall, it produces seedheads with spiny burs. These spines can be quite painful if you step on the plant barefoot. Coastal sandbur tends to be found in sandy soils, although it can grow in other soil types. There is a winter annual broadleaf weed called lawn burweed or spurweed (Soliva sessilis), but this plant may also be called sandbur. This broadleaf weed will germinate in fall and flower in spring, forming spine-tipped burs. So we ask the caller, “Is the weed you are calling about a grass or a broad-
Virginia Tech Researchers: Jeffrey Derr, Ph.D., Professor of Weed Science, and Adam Nichols, Research Assistant, Hampton Roads Ag. Research and Extension Center, Virginia Beach Research Sponsors: The Virginia Turfgrass Foundation and the Virginia Turfgrass Council
A
grassy weed that can be a significant problem in turfgrass is coastal sandbur (Cenchrus incertus, also listed as Cenchrus spinifex). First, we want to address an issue that
we often have to answer. When we get a call about controlling sandbur, we have to ask the caller some questions to make sure we both are talking about the same weed species. Coastal
Treatment
Rate (lb. ai/A)
Number of sandbur plants at 1 month after application
Shoot fresh weight reduction at 1 month after application
Nontreated
—
22.8
Pendulum AquaCap
3.0
Barricade 4L
Treatment
Rate (lb. ai/A)
Number of applications
Percent control 1 month after 2nd application
0
Nontreated
—
—
—
2.0
78
Monument
0.025
2
50%
0.75
1.7
93
Revolver
0.04
2
51%
Specticle FLO
0.05
3.7
71
Pylex
0.02
2
100%
Ronstar 2G
3.0
4.3
69
Acclaim Extra
0.13
1
100%
Dimension 2EW
0.5
2.6
98
Tenacity
0.25
2
25%
Tenacity 4L
0.25
16.2
41
MSMA
2.0
2
99%
Table 1. Preemergence control of coastal sandbur.
Table 2. Trial 1 — Postemergence control of coastal sandbur.
Photo 1. Coastal sandbur plant.
Photo 2. Coastal sandbur seedhead (painful burs!).
18 | Virginia Turfgrass Journal May/June 2016 www.vaturf.org