Metam sodium should be applied in the center of rows during bedding of soil. Using a bedshaper to smooth beds helps improve the performance of herbicides such as metolaclor (Dual) which can be surface applied immediately after application of metam sodium. To avoid crop injury by DNA-type herbicides (Prowl) that are soil incorporated prior to soil fumigation, herbicide rates should be reduced to the lowest recommended rate for the soil type. This helps to avoid root injury by concentration of herbicide in the row during bedding of soil.
RECOMMENDATIONS FOR CBR CONTROL WITH METAM SODIUM | |||
|
|
|
|
|
|
Metam 42% Vapam 42% |
7.5 gal 7.5 gal |
Use with NC 10C or NC 12C in cases of severe disease pressure; plant other varieties only in cases of moderate to light CBR pressure. Apply 8 inches deep at least 14 days preplant with injector shanks (one per bed) in front of a disk bedder with a bed shaper to mark rows. Do not mix treated with untreated soil by tillage or other cultural practices after application. |
Read cautionary statements and all directions on the product label. Metam sodium is corrosive, can damage skin, and irritate eyes, nose and throat. Personal protective equipment must be immediately available to workers in an enclosed cab and worn if the handler leave the enclosed cab to perform any direct contact activity. See details on product labels. |
Several manufacturers offer equipment for application of
soil fumigant and bedding rows. Squeeze pumps, roller pumps and
diaphragm pumps have been used successfully to achieve uniform
application of fumigant in each row. Bedding rows helps to increase
soil temperature and mark the placement of the material. Smoothing
beds with a bedshaper improves the performance of surface applied
herbicide after fumigation.
A coulter in front of chisel shanks serves to cut through
corn and cotton stalks that would otherwise accumulate on chisels
shanks. Microsclerotia of the black rot fungus are commonly found to
depths of 8 inches and occasionally up to 10 inches below the soil
surface. Metam sodium should be applied 8 inches below the original
surface of the soil ahead of the disk-bedder and bed shaper.
Shallower depths may fail to kill fungal inoculum at depths below
treatment, while deeper application may slow activation and limit
upward movement.
To avoid potential crop injury, applications must be made
14 days prior to planting and after soil temperatures are likely to
remain above 50 degrees. Optimum conditions for soil treatment are
thought to occur when soils are moist and soil temperatures are
between 60 and 65 degrees at the 4-inch depth. Soil temperatures
below 50 degrees will interfere with conversion of the chemical into
the active ingredient which kills microsclerotia of the fungus in
soil.
Calibration of equipment can be performed using water, since its flow rate is about the same as commercial formulations of metam sodium. Before attempting calibration, the equipment should be set to deliver the fumigant to the required depth and shape beds in a manner that will seal the soil surface.
Applicators with diaphragm or roller pumps can
be calibrated in the standing position using a stop watch. The first
step in calibration of these units is to determine the ground speed
that is most comfortable for the operator. This can be done by
measuring a distance of 113.4 ft and determining the time required to
travel this distance in the field. Speed should be determined with
the applicator at the required depth and shaping beds satisfactorily.
Once a comfortable speed is established, it is recommended that at
least three trials be made to establish uniformity. The adjacent
chart uses the 1/128th of an acre method to determine application
rate. Each fluid ounce collected is equivalent to 1 gal/A. While this
method offers the advantage of simplicity, its accuracy depends
entirely upon the maintaining a uniform speed in the field.
Applicators with squeeze pumps must be calibrated by collecting the output over a measured distance in the field. Speed is not critical, since output of the pump is a function of travel. It is best to calibrate these units with the applicator inserted into the ground and operating as if fumigant were being applied. If rows are spaced the standard 36-inches apart, the 1/128th of an acre method would require measurement of output over 113.4 ft of row. As above, each ounce collected is equivalent to 1 gal/A.
Introduction Symptoms & Signs Causal Organism Cultural Practices References
|
|
http://ipm-www.ento.vt.edu:8000/nipmn/VA-IPM/cblackrot/chemical.htm
Last Updated on March 5, 1998 by Barron Britt Keeling