PREEMERGENCE TREATMENTS TO CONTROL WEEDS IN ORNAMENTAL PLANTINGS -- Continued
A repeated treatment is needed for seasonal control.
DCPA (10-12,WP or G;
Preemergence to weeds.
Many annual grasses, and
Resistant broadleaf weeds are ragweed, galinsoga, and
some broadleaf weeds for
many others. Registered for use on 52 ornamental annu-
als, perennials, and bulbs, several ground covers, and a
broad range of woody plants and turfgrasses. It is no
hazard downslope. It is a safe choice for pathways
(baseball fields), patios, flower beds, and mixed plantings.
Dichlobenil (4-6, WP&G;
Highly volatile, and has been consistently effective when
Broad range of annual and
Late fall or early spring,
applied in late fall or early spring just before snow or
perennial weeds, including
rain, or just before mulching in the spring. Safe on many
nutsedge, quackgrass, field
woody plants and certain ground covers, but not herba-
horsetail, mugwort, and
ceous plants or bulbs. Also susceptible are azaleas,
hemlocks, true firs (Abies spp) and Douglas-fir. Dormant
applications should be followed in the spring with a
preemergence annual grass herbicide. Moderate to high
hazard to turfgrass downslope unless treated area is
mulched. A good choice for control of many established
perennial weeds in established tolerant woody plants.
Controls weeds for 2-4 months. Resistant weeds are
Diphenamid (4-6, WP;
Preemergence, before light
Annual grasses and several
ragweed, galinsoga, and many other broadleaf weeds.
rain or sprinkler irrigation.
broadleaf weeds, such as
Safe on several herbaceous plants, ground covers, dichon-
carpet weed, chickweed,
dra, and a broad range of woody plants. Moderate hazard
to turfgrass downslope.
pigweed, purslane, and