Controlling red rice requires a program approach that uses
good management – a combination of preventive, cultural
and chemical methods in conjunction with crop rotation.
Preventive measures include planting high-quality rice
seed and using clean equipment and machinery in farm operations.
Use of high-quality rice seed free of red rice is extremely important
in preventing the introduction of red rice into a field.
After working a field infested with red rice, whether during field
preparation or harvesting,
clean machinery before
moving to the next field to
prevent introducing red rice
seed into other fields. Mud
and other debris that cling
to tractors and cultivating
equipment can contain red
rice seed that can be moved
into a red rice-free field.
During seedbed preparation,
destroy all red rice
plants in the field before
planting. Because red rice
is more vigorous and grows
faster than commercial rice,
give commercial rice an opportunity to compete effectively with red
rice by planting it at the suggested (or at a slightly higher) seeding rate.
Red rice tillering and seed production is decreased when competition
from commercial rice is high.
Use proper water management to suppress red rice effectively.
Permitting soil to dry out and re-wet encourages the germination of
weed and red rice seed. Water-seeding in combination with good
water management helps suppress red rice. Two suggested techniques
are continuous flood culture and the pinpoint flood system. In
these systems, it is important to flood immediately after seedbed
preparation. Delayed flooding allows red rice seed to germinate and
get established, resulting in a loss of red rice suppression.
Post-harvest management is critical in red rice management. High
moisture red rice seed incorporated in the soil may remain dormant
for many years. Red rice seed left on the soil surface over winter
will lose dormancy. These seed will germinate by March and can
be killed by cultivation. Red rice will lose its dormancy through a
series of wetting and drying cycles. A winter with alternating dry
and wet periods most likely will result in severe red rice pressure in
the following season. A wet winter generally results in lower red rice pressure the next season.
Although continuous and pinpoint flood cultures suppress red rice,
they may not provide adequate control. To improve control, use herbicides
in combination with specific water management techniques.
Newpath can be applied only to CLEARFIELD rice varieties and
provides very effective control of red rice. Two applications are critical
for control. The first application can be applied preplant and
incorporated or at spiking to one-leaf rice or red rice. The later application
has proven to provide better red rice control. The second application
should be applied at four-leaf rice or red rice. Applications
made later (five- to six-leaf) may reduce control. It is important that
the herbicide be activated immediately after application with a flush
or rainfall. The best control is obtained when the flood is applied no
later than seven days after the last application.
Field selection is critical. Non-CLEARFIELD rice fields and other
crops are extremely sensitive to drift. Escapes can occur in either of
these chemical management systems. In the CLEARFIELD/Newpath
system, Beyond at 5 oz/acre can be used to control escapes. Beyond
can be applied between late tillering and panicle initiation. Beyond can
be applied only following two applications of Newpath. It is strongly
escapes be rougued from
fields before heading.
Stale Seedbed Technique
Another method of red
rice control is to use the
fall or spring stale seedbed
cultural management system.
Keep it idle or stale
to allow germination and
growth of red rice. If necessary,
fields may be
flushed to maximize red
rice seed germination.
When red rice is actively
growing and 4 inches tall
or less, apply 1 quart of 4
lb a.i./gal glyphosate. When applying by air, apply 3 to 5 gallons of
water per acre. Application to red rice growing in saturated soils is not
as effective as in moist soils. Normal production practices are then followed.
For the most effective control of red rice, wait at least six
days but not more than nine days after application to flood and plant
using the water-seeded method.
The most practical and economical way to control red rice is to
rotate grain sorghum and soybeans with rice. Two suggested threeyear
crop rotations are soybeans/soybeans/rice or grain sorghum/soybeans/
rice. When growing soybeans in these rotations, use a herbicide
such as Frontier, Lasso, Dual or Treflan at recommended label rates.
Planting grain sorghum in the rotation and using atrazine is also
effective. Although red rice can be controlled with these herbicides,
early cultivation and application of a selective post-emergence soybean
herbicide such as Poast, Select, Fusion, Assure II or Fusilade DX
are necessary to control any red rice that escapes the soil-applied
herbicide. It is important to plant alternate crops for at least two years
before rice to achieve satisfactory control of red rice.
Contact McCauley at (979) 234-3578 or firstname.lastname@example.org.