| Material Information
||Control of weeds and nematodes in shade tobacco beds
||NFES mimeo rpt.
||2 leaves : ; 28 cm.
||Kincaid, Randall R ( Randall Rich ), 1903-
North Florida Experiment Station
||North Florida Experiment Station
||Place of Publication:
||Tobacco -- Weed control -- Florida ( lcsh )
Nematode diseases of plants -- Control -- Florida ( lcsh )
||government publication (state, provincial, terriorial, dependent) ( marcgt )
non-fiction ( marcgt )
||Statement of Responsibility:
||by Randall R. Kincaid.
||"August 14, 1956."
||Florida Historical Agriculture and Rural Life
F 3( /t6
NORTH FLORIDA EXPERIMENT STATION
Quincy, Florida -x
August 14, 1956
NFES Mimeo Rpt. 57-3
a FEL 6 1957
CONTROL OF WEEDS AND NEMATODES IN SHADE TOBACCO BEDS
by Randall R. Kincaid, Plant Pathologist
Preparation of beds is an important factor in the success of an e
three methods given below. Broadcast soil conditioners manure or peanut hulls -
before treatment. Harrow and moisten the soil about 5 inches deep a month or more
in advance to permit plant materials to decay. Apply treatments when the soil
is moist, but not too wet to plow; moisture makes weed seeds easier to kill, and
promotes the activity of the chemicals. Cut weeds around the bed, and provide
ditches to protect the soil from washing.
Fumigation, Urea and Cyanamid Treatment.--Fumigate the soil for nematode
control, about 10 days in advance of the weed-control treatment, with 15 gallons
of 40% EDB (Dowfume or Soilfume) per acre broadcast, as in shade fumigations
Then, about the last of September, broadcast 1 pound of urea (NuGreen) and
pound of cyanamid per square yard uniformly on the soil and mix the materials
thoroughly with the soil 4 to 5 inches deep. Mix preferably with a rotary tiller;
or at least four to six times with a disk harrow, starting with a very shallow
depth to avoid concentrating the chemicals in bands, and gradually increasing
the depth. Smooth the soil, and leave undisturbed for a month. Afterwards, water
the bed if the weather is dry.
Treatment with urea and cyanamid gave good weed control and plant growth
for 8 years in succession on the same plots at this Station.
Fumigation and Cyanamid Treatment.--Fumigate the soil as described above.
Broadcast 1 pound of cyanamid per square yard about the last of September, and
proceed as above. Thorough mixing of cyanamid with the soil is probably even more
important than with the combination of urea and cyanamid.
Treatment with cyanamid alone gave equally good weed control and plant
growth in the 8-year test as did urea and cyanamid, and was less expensive.
Methyl Bromide Treatment.--Treatment with 1 to 14 pounds of methyl bromide
per 100 square feet, properly applied under gas-tight plastic covers, has given
good results in controlling both weeds and nematodes. Details of the method may
be obtained from local dealers. The treatment may be applied in November or
December, whenever temperature and moisture conditions are right.
Growers are cautioned not to wait too late to make preparation for the
treatment, since there may be unavoidable delays due to unfavorable weather or to
the crowded schedule of custom operators. To avoid possible reduction in stand,
treatment should be completed not later than a week before sowing.
Mimeo Rpt. 57-3 continued
Other Methods.-This Station continues to test new materials which appear
promising for weed control. Tests are conducted on plots 6 x 7 feet, in quadru-
plicate randomized blocks. Treatments are applied about the last of September.
Weed and seedling counts are made on an area 3 x 5 feet in the middle of each plot.
The 1956 tests compared the combination of NuGreen (1 pound per square
yard) and Cyanamid (I pound) with two rates of Cyanamid alone, and Vapam in
liquid form applied by two different methods. All dry treatments were mixed with
the soil 5 inches deep by means of a rotary tiller. One of the Vapam liquid
treatments was likewise mixed; followed by a water seal. The other Vapam liquid
treatment was applied as a drench after rotary tillage.
There were no untreated checks, but treatment with N-869 (Vapam in dry
form), which had lost most of its active ingredient, gave some indication of the
potential weed count. Results were as follows:
Weeds Cumulative yields of
per seedlings per sq. yd.
square March April
Treatment per square yard yard 26 30 3 Stand
NuGreen 1 lb. / Cyanamid lb. 101 33 138 238 330
Cyanamid I lb. 138 10 132 223 340
Cyanamid 1 Ibs. 130 22 134 224 333
Vapam 1/6 pt. mixed and sealed 48 20 120 219 329
Vapam 1/6 pt. applied as drench 59 21 132 209 301
N-869 (see text) 194 17 125 214 315
Least significant difference, 5% 66
Vapam liquid treatments gave better weed control than Cyanamid alone or
in combination with NuGreen; some of the differences were significant at the 5%
level. Seedling yields from the various treatments were about the same.
Vapam is a promising material, but further tests will be conducted
before it is recommended to growers.
Bedrench, a new material containing allyl alcohol and ethylene dibromide,
will also be tested.