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Compost as an Alternative to Methyl Bromide
in Bell Pepper Production
Ted Burch, Burch Farms,
Faison ,
NC
Lewis Flynn, McGill-Leprechaun, Harrells ,
NC
Introduction
American farmers maximize yield and
income per acre by using mineral fertilizers,pesticides, multiple tillage, and cropping.
These cultural practices have had a significant
negative impact on the soil, its organic content,
biologic activity, and productive capacity, and has led
to a dependency on high cost material inputs.
Many growers must rely on soil fumigants
for the production of certain crops.
Methyl bromide’s removal from the market in 2005 has
stimulated considerable research to find alternatives to
this widely-used product.
Objectives
Burch Farms operates an
extensive packing and growing operation in
Faison,
NC. Compost, purchased
from McGill,
is applied annually to more than 1,500 acres at Burch
Farms, producing 3,500 acres of leafy greens, cabbage,
squash, eggplant, cantaloupe, and a variety of specialty
crops.
The McGill trial was prompted by the
results of a three-year study of methyl bromide
replacement with
compost in strawberry production conducted by Dr. Frank
Louws,
North Carolina
State
University.
Twenty-six acres located at
Lake Artesia Road,
Sampson County,
North Carolina, were set aside for the
McGill trial. The field is a Norfolk
Sandy Loam soil type that had been used the previous
year as a nursery for sweet potato plants.
During the spring of 2001,
the entire trial field was turned with a mole board
plow, then disc harrowed. A six-acre
block was delineated on the north side of the 26-acre
field. McGill's Soil
Builder Compost was broadcast on the six acre trial
block at a rate of 35 cubic yards to the acre.
Preplant fertilizer was
applied to the 20 acres without compost at the full
recommended rate of 1,000 pounds 6-6-18 per acre.
Three-foot plastic covered beds were
formed on 72-inch centers. Beds in
the 20-acre control block were fumigated with 50 pounds
of methyl bromide. The 6-acre
composted block was not fumigated; however, a single
application of Treflan/Command was made
with good results to control weeds emerging in the open
ground centers of the compost block.
On April 15, King Arthur
variety bell pepper plants were set in double rows at a
population rate of 14,000 plants per acre.
On April 18, a late frost put the crop in
jeopardy. Two helicopters were
brought in prior to dawn that morning, keeping the frost
from settling and saving the crop.
Over the next 60 days, the compost and
methyl bromide blocks were similarly drip irrigated and
fertigated with CN 9 and 408.
Kocide and Manzate fungicides,
along with Spintor insecticide, were spray
applied at similar rates to both blocks.
Results and Discussion
Observations made during the grow-in of
both the compost and methyl bromide blocks noted no
significant difference in plant health or growth.
Soil and tissue samples indicated similar plant
nutrient levels, consistent with the recommended ranges
for the corp.
Crop weight yield results were gathered
on June 22, with four random sample harvests of 120
plants taken from both the control and composted plots.
The results indicated a 38% yield increase by
weight in the composted block.
On June 25, the first field harvest was
conducted, with five rows each take from the control and
compost plots. The harvest grade and
quality of peppers harvested from both blocks was high.
The results were 3,087 boxes from the fumigated
block and 4,327 from the compost block – a 40% yield
increase.
The cost of the McGill Soil
Builder Compost applied was $385 per acre.
A single herbicide application to the compost
block of 605T was $25 per acre.
Fifty percent less preplant fertilizer applied to the
compost plot, combined with a savings of $300 per acre
in fumigation costs, gave a total per acre materials
savings of $350 on the composted plot.
In total, the cost of replacing methyl
bromide with compost in this trial was an additional $60
per acre.
Conclusion
It is expected that the price of methyl
bromide will increase annually over the next three
years, prior to its removal from the market in 2005.
Compost used as a replacement for methyl
bromide encourages an active, rather than a sterile,
soil biology while improving soil tilth and providing
nutrients for the principal and succeeding crops.
This trial’s high rate compost
application block earned a significant dollar return
only $60 in additional production expense.
A 40% yield increase translates into 600
additional boxes of bell pepper per acre.
Results of this trial demonstrate that
compost application can be a lower cost alternative to
methyl bromide and can significantly increase yield and
per acre income.
Burch Farms intends to replace all of its
soil fumigation with compost.
All production and
management expenses for this study were borne by Burch
Farms. This study was also funded, in part, by a grant
from the North Carolina Department of Environment and
Natural Resources, Division of Pollution Prevention and
Environmental Assistance. |
