Arkansas Agriculture Newsletters
Arkansas Weekly Crop Report - August 2, 2006
Soybeans •
Cotton
Soybeans
Arkansas Soybean Crop Situation - Trey Reaper
Several early-planted fields across the state
are at or approaching R6, and irrigation termination decisions will
have to be made. Before making any decision regarding irrigation
termination, be sure to determine which growth stage the crop is
actually in. A soybean plant has reached the R6 growth stage when
one of the top four nodes with a fully developed leaf has a
pod with green seeds that fill the pod cavity. At this point, you
will need to evaluate the available soil moisture in conjunction
with the plant's growth stage.
There has been some confusion as to what is the
best time for irrigation termination. The Soybean Production
Handbook states that a practical rule of thumb for termination is
when 50% or more of the pods have seeds that are touching and there
is good soil moisture. This has been a good rule of thumb for
maturity group V's and VI's (determinates), but this may not be a
good rule for early-planted fields and earlier maturing varieties (indeterminates).
Some group III and IV varieties may have 50% of pods with seed
touching, yet they may still not be a full R6 because of the
indeterminate growth habit (pods develop from the bottom upward).
The safest and most practical approach is to consider irrigation
termination when the field can be classified as being in the R6
growth stage. If a plant has reached R6 and there is plenty of
available soil moisture, irrigation may be terminated with little to
no effect on yield in most years.
Studies conducted by Phil Tacker and others in
2005 indicated that in certain cases, irrigation beyond the R6
growth stage resulted in increased yield in earlier-maturing
varieties. Keep in mind that this observation is based on one year
of data, and these studies are being repeated in 2006 for further
verification.
The studies were
conducted in southeast Arkansas at Rohwer and included MG III and IV
varieties. For the MG III variety, a five-bushel increase (64 vs.
59) was achieved with a final irrigation at the R7 growth stage
(mature-colored pod on the main stem). Notice that no late-season
rainfall occurred beyond R7, and daytime temperatures were 95o
to 100o F until harvest. Only a one-bushel difference
was observed for the MG IV variety between irrigation termination at
R6 and R7. However, late-season rainfall occurred before the plants
fully matured, and daytime temperatures until harvest were less than
95o F. Treatments that were not irrigated at the R7
growth stage may have responded to the late-season rainfall and
lower temperatures.
These studies offer only one year of data, but
unfortunately 2006 is shaping up to be very similar to the
conditions we experienced in 2005. This data indicates that
terminating irrigation early, especially prior to the R6 growth
stage, can result in lost yield potential. Furthermore,
early-maturing soybean varieties may respond significantly to
late-season (R7) irrigations, particularly when rainfall does not
occur past R7 and temperatures are relatively high.
When deciding when to terminate irrigation,
consider how much cost and effort is required for just one more
irrigation. This decision may be relatively simple for
center-pivot, furrow, and border-irrigated fields. Flood irrigated
fields can make this decision more complex due to cost and time.
Regardless of irrigation method, nearly all the input costs have
been expended when the irrigation termination decision has to be
made. Don't sell these fields short at this point, as the final
irrigation may make the difference between a 40- and 50-bushel
crop - especially in a hot, dry year like we are currently
experiencing.
The first harvest
reports have come in for this growing season. Unfortunately, these
fields were non-irrigated and experienced accelerated maturity due
to hot, dry conditions. Carl Hayden (Chicot County) and Robert
Goodson (Phillips County) both reported that March-planted fields
have been harvested in their counties with less than favorable
yields ranging from 12 to 30 bu/ac. Most areas in the state have a
good chance for milder temperatures and possibly rainfall over the
next several days. Hopefully this will allow plants, especially in
non-irrigated fields, to increase overall seed size and yield.
Soybean Research Verification
Reports
North SRVP (Trey Reaper):
Irrigated fields continue to improve each week, as all fields have
reached the reproductive growth stages. Fields in Clay and
Randolph Counties have reached R3 and will continue to be
irrigated in a timely manner. The Lawrence Co. field is approaching
R6 and will require at least one more irrigation. Some SDS was
noticed across the field this week, but stinkbug levels are very low
thus far. The Perry Co. North field has reached R3 and looks
great with very limited disease and insect pressure at this time.
The field caught over an inch of rain late last week, but irrigation
will resume in a couple of days. The Perry Co. South field has
reached full bloom and received 0.5" of rain late last week. The
Sebastian Co. field has a good pod load, but lack of rainfall
has prevented seed development for the majority of the field. The
field has received less than 5" of rain since R2. Stinkbugs are
just at treatment threshold, but we will wait a few days to explore
application costs and options as well as evaluate the overall yield
potential of the crop. The Craighead Co. field is in
excellent condition and is approaching R6. We plan on irrigating
the majority of the field up to R7 while terminating irrigation at
R6 on a portion of the field. This field has a very light soil
type, and we could see a yield increase from later irrigation. The
Mississippi Co. field has also reached full bloom and is in
good shape so far. The Crittenden Co. field responded well
to irrigation and looks good with the exception of areas that did
not achieve a good stand. Barnyard grass escapes may be difficult
to control, as the Select application was delayed. The Phillips
Co. field has reached R6 with good soil moisture; therefore,
irrigation has been terminated on this field. The field, which has
a clay loam soil, has good overall water holding capacity. Stinkbug
levels have not increased, and while they are not at treatment
threshold, next week will be the third week in a row, and we may
need to consider treatment.
South SRVP: SRVP fields in south
Arkansas are in fair to good condition. In the dryland Lafayette
Co., field beans are beginning to touch in pods. Some downy
mildew and frogeye is present but has not spread much in the last
week. A number of green stink bugs were found when we scouted the
field; however, numbers are below threshold. We will look again
this week and consider treatment if numbers are at threshold
levels. In Jefferson Co., plants are at varying stages of
reproductive development. Older plants are at R5, while younger
plants and plants that were stunted by standing water are at R3.
Insect pressure is low, and a small amount of frogeye and downy
mildew was found this week. The likelihood of treating for foliar
disease is minimal at present, but we will keep a close eye on the
situation. The Ashley Co. field looks very good at present
and has been irrigated seven times so far this season. Some
stinkbugs were present last week; however, the numbers were below
threshold level. We will check again this week and make a decision
in efforts to maintain what looks to be an excellent yield
potential. Fields in Arkansas and Drew counties look good
and are in the R3 growth stage. The program's only double-crop
field has really started growing in Desha Co. The field was
sprayed last week with a tank mix of glyphosate and Classic in
efforts to control some large morning glories. Irrigated SRVP
fields are being watered about every week, and all fields are being
closely monitored for insect and disease pressure.
Soybean Economics – Bob Stark – July 24, 2006
The weekly average Arkansas cash soybean price
fell from the previous weekly average of $5.87 to $5.66 for the July
17–21 week. Daily averages were in retreat throughout the week,
sliding from $5.70 on Monday to $5.58 per bushel on Friday across
the nine state markets that continue to report to USDA–NASS.
Overall, the market price fell 27 cents from the previous Friday
close, including a 13-cent decline on Monday alone. Highest daily
market price of this past week was recorded at $5.79 on July 17 at
Helena and lowest price was $5.39 on July 21 at Wynne.
The July 3–7 surge in weekly averages for old
crop Arkansas soybeans seemed to be holding in place prior to the
current week change. Market analysts continued to cite the bearish
fundamentals of large stocks and expected high 2006 production,
despite some slight positive movements in each measure along with
reports of unfavorable weather conditions and falling USDA crop
ratings.
Many Arkansas soybean producers continue to
book an increased percentage of their 2006 crop. For New Crop No. 1
Yellow Soybean Prices (across the fifteen reporting state markets),
the state average for the week was $5.73 per bushel, a fall of 22
cents from the previous weekly average of $5.95 per bushel. New
crop beans were found to be about 7 cents above the old crop average
price for the same weekly period.
Soybean Ruse Update – July 27, 2006
Cliff Coker and
John Rupe
Yesterday, July 26,
LSU announced the discovery of Asian soybean rust on infected
soybean leaves from sentinel plots at the Dean Lee Experiment
Station near Alexandria, LA (Rapides Parish). The disease has not
been found in commercial soybean fields in Louisiana yet.
We are starting to
get a lot of calls and questions concerning the situation in
Louisiana and what it may mean for Arkansas soybean fields.
We see no reason
to panic at this time. The find in Louisiana is still 150 miles
south of the Arkansas border, and weather conditions here do not
favor disease development. Unless rust is detected closer to
Arkansas, we see no reason to start spraying fungicides yet.
For growers
currently spraying high yield-potential soybean fields for
preventative reasons - as is the custom in some parts of the state - we
also do not see any reason to shift fungicides. Headline or Quadris
alone should still be the materials of choice unless things change a
lot over the next few weeks.
We have intensified
our scouting in southern Arkansas in order to stay in front of any
changes and will keep you informed.
Keep in mind that
current economic conditions and the limited yield potential of many
soybean fields in the state make it very important to make the best
decision possible - at the correct time - in order to maximize any
economic benefit from a fungicide application. Fields now at R5 and
later have likely outrun the disease this year. Please call your
local county Extension agent for assistance in developing a
fungicide plan for your soybean acreage, if needed.
LSU Press Release Follows:
LSU AgCenter NEWS
LSU AgCenter
Communications
Knapp Hall
Baton Rouge,
Louisiana 70894‑5100
Phone: (225)
578‑2263 Fax: (225) 578‑4524
Distributed
07/26/06
Asian Soybean Rust
Confirmed On Louisiana Soybeans
LSU AgCenter
scientists confirmed Wednesday (July 26) that Asian soybean rust was
found on soybeans in Rapides Parish.
This is the first
finding of the disease on soybeans in Louisiana for 2006. It had
been found about a month ago on kudzu, a plant that can host the
disease, in Iberia and Lafayette parishes.
The discovery on
soybeans came in the central part of the state in a sentinel plot on
the LSU AgCenter's Dean Lee Research Station in Alexandria. The plot
is one of 15 in the state planted early to give scientists a
heads‑up in case of a disease outbreak.
"It's been raining,
providing the warm, humid conditions this disease likes," said Dr.
Clayton Hollier, LSU AgCenter plant pathologist. "We suspect if it's
been found here, it is also in other soybean fields in the state."
The recommendation
to farmers is that they treat vulnerable fields with a fungicide to
halt the disease's growth. They can get the fungicide
recommendations from any LSU AgCenter agent or on the AgCenter's Web
site (www.lsuagcenter.com).
This must be done
on a field‑by‑field basis, based on the growth stage in the field
and any treatments that have already been applied," said Dr. David
Lanclos, LSU AgCenter soybean specialist. "We're not recommending
blanket spraying. Producers can contact anybody at the LSU AgCenter,
and we'll help them with a plan to protect their crops."
Lanclos said up to
70 percent of the total soybean acreage in the state (830,000 acres)
already has reached a maturity stage in which the disease, even if
it occurs, will not hurt yields. In those cases, beans "already have
been set." The disease causes defoliation, which stops
photosynthesis and thus plant growth.
Unfortunately, the
rest of the soybeans in the state were planted later, and beans are
still forming, he said.
"There are nine
parishes in the state that traditionally plant their beans later,"
Lanclos said. "These soybean fields are particularly vulnerable."
The nine parishes
where soybeans generally are planted later are in the south central
and southwestern parts of the state and include Acadia, Avoyelles,
Beauregard, Evangeline, Jefferson Davis, Pointe Coupee, Rapides, St.
Landry, and St. Martin.
Hollier, who
analyzes about 1,500 suspect leaves taken from across the state each
week in his lab, said the leaves from the plot where the disease was
confirmed were thick with disease spores.
"Several
sporulating pustules were found on 75 percent of the leaves taken
from the plot," Hollier said. "This means the disease was well on
its way."
Asian soybean rust,
which has the potential to devastate soybean yields because of its
ability to spread fast, already has been confirmed on soybeans in
Alabama and Georgia in the past few weeks, Hollier said. Scouting
efforts are under way throughout the United States.
Please contact your local county Extension office for more
information on soybeans in Arkansas.
Cotton
Crop Status
(Bill Robertson -
Extension Agronomist, Cotton and
Frank Groves - CRVP Coordinator)
As of July 24, the Arkansas Statistical Office
of the National Agricultural Statistics Service reported boll set
occurring on 93% of the acreage, compared to 75% last week, 86% last
year, and 83% averaged over the last five. The condition of the
crop is 1% very poor, 6% poor, 28% fair, 48% good, and 17%
excellent.
The hot conditions of last week have been replaced by highs in
the upper 80s, lows in the mid 70s and a 60% chance of showers
toward the end of the week. The cloudy conditions of last week
failed to cause excessive shed, and we have still managed to avoid
the "big one." Fruit retention values are consistently in the
90-95% range, and the potential exists for a good crop. Most of the
crop is at or near physiological cutout (NAWF=5). Although we may
be reaching cutout earlier than normal according to the calendar,
the crop has generally been on or slightly behind pace for most of
the season.
Varying levels of a condition referred to as phomopsis,
cavitation, or boll dangle can be found in most fields across the
state. Although several theories exist, the cause and cure for this
physiological phenomenon remain unclear. In the past this condition
has sometimes been observed at greater levels in later maturing
varieties with DP90 backgrounds. However, it is not restricted to
the later-maturing varieties. We have received a number of calls
concerning this in DP445BG/RR this season. Similar symptomology was
observed in this variety last year, which in spite of this
occurrence performed very well in Arkansas as well as other states
across the Belt.
Cotton
Research Verification Program Update
(Frank
Groves - CRVP Coordinator)
Fields continued to follow the target
development curve of COTMAN this week and NAWF values were around
six. Cavitation was prevalent across all CRVP fields observed this
week. The loss primarily affected lower first-position bolls and
was greater in south Arkansas. Despite physiological shed due to
cavitation and cloudy conditions, fruit retention remained high
(90-95%).
Plant bugs numbers appear to have rebounded.
The Mississippi-Costner field (ST 4686R) was treated for plant bugs
(1 per 1.2 ft), Heliothis spp. (1 per 3 ft) and saltmarsh
caterpillar (3 per ft). Plant bugs were also treated in the
Chicot-Pool field. The unusual number of bollworms found in the
terminal of plants last week subsided this week. The high numbers
across multiple varieties of first generation Bt cotton was
alarming, but proved to be insignificant with time.
Cotton Insect
Pests
(Gus
Lorenz – Extension Entomologist)
With recent high temperatures, we have begun to
receive calls on treatment failures. In many cases, the reason has
been improper selection of insecticides, but in others it may be
application problems, mainly lack of adequate volume. Also, I
continue to receive calls on tank mixing several products in one
application. One person told me last week that he was spraying two
insecticides, boron, three gallons of fertilizer, and 8 ounces of
mepiquat chloride in one application with a total volume of four
gallons per acre. I'm surprised it would even spray through
the nozzles. My question is, "What's more important - getting
all that stuff out in one application or controlling insects?"
Plant bugs appear to be making a
comeback as our cotton crop rushes toward termination. Plots at
Soudan (Lee County) this week hit the one plant bug per row foot
level. Greg Smith, consultant in Mississippi County, reported
several fields over one per row foot. We have received a few
reports on lack of control with acephate in Arkansas, and
particularly in Louisiana and Mississippi. Stoneville researchers
Gordon Snodgrass and Jeff Gore are reporting high levels of
resistance in plant bugs collected in Mississippi in several fields.
Bollworm/Budworm trap counts finally
began to fall last weekend in most of southeast Arkansas. However,
we began kicking up budworm moths in our plots in Jefferson County
and are still seeing eggs in the cotton. Danny Moore, consultant in
Poinsett County, reports seeing several budworm moths in fields this
week. Many folks have attempted to control worms in conventional
cotton in the last week with a pyrethroid and have experienced
varying degrees of control failures. If you apply a pyrethroid in
conventional cotton and find worms 3 to 4 days after application,
it's probably a good idea to make some changes in your insecticide
selection. Recent larval collections by Glenn Studebaker indicated
fields in northeast Arkansas were 50/50 budworm/bollworm. Greg
Smith identified larvae he collected as 40% budworm. I would
suggest you treat this population accordingly in conventional
cotton.
We have received several reports of terminal
and square damage in Bollgard cotton this year. It certainly does
not appear to be any one variety, but rather a general trend.
Whether or not this is a factor of environmental conditions or
increasing bollworm tolerance is not known at this time, but it is
certainly something we will have to monitor. During the recent
bollworm flight, we observed some fruit and terminal damage in
WideStrike cotton. Stephen Wall also reported treating WideStrike
cotton twice for bollworms. However, this week in our plots, while
worm counts remained high in conventional cotton, the WideStrike
plots were relatively free of damage. This serves to remind us that
we need to stay vigilant and scout all cotton closely for developing
problems.
Fall Armyworm numbers appear to be
increasing statewide and may become a major concern for us as the
end of the season quickly approaches. Bobby Griffin reported today
that about 30% of the worms he saw in fields this week were FAWs.
We have seen an increase in FAW numbers in our plots in Jefferson
County. Remember to look for developing populations down in the
plant. Look for the "windowpane" appearance on boll bracts and
leaves. It's much easier to control FAWs when they are small.
Mites continue to cause problems in many
areas. Recent trials conducted this week and last continue show
that bifenthrin products, Discipline, Fanfare, and Brigade (formerly
known as Capture), provide decent control in most situations.
Denim, a sister compound of Zephyr, should provide good suppression
of spider mites, particularly on conventional cotton if worm
applications are necessary.
Cotton
Economics
(Scott
Stiles and
Rob Hogan Extension Ag Economists)
Crop Conditions Deteriorating; A Second
Chance to Purchase .58 Calls
The weekly USDA crop ratings reveal the
severity and impact of the dry weather conditions seen over the past
month. Much of the decline in the condition of the U.S. cotton crop
can be attributed to Texas. Since June 25th, roughly
one-half of the Texas crop has been rated as "poor" to "very poor."
Because there has been no relief from recent 100-degree
temperatures, crop conditions may continue to deteriorate. Some
analysts are willing to venture that the Texas cotton crop could
fall to 4 million bales. That reflects very poor yields and
substantial abandonment given the fact that the USDA recently
estimated that 6.4 million acres were planted in the state.
30-Day Weather Outlook
The NOAA recently released its 30/90 day
outlook. Above-normal temperatures are expected to continue over
the next 30 days for all of the southern U.S. (except the
Carolinas). Texas, Oklahoma, Arkansas, Louisiana, and Mississippi
could experience "much above" normal temperatures in August. Texas,
north Louisiana, and Arkansas (except for extreme northeast
Arkansas) are expected to remain in an area of "below normal"
precipitation as well.
Marketing Strategy
As this article is being written, December
cotton futures have traded up to one-month highs. Perhaps the
traders are following the weather? Since the release of the June 25
Weekly Crop Progress report, market prices have traded back and
forth. But December '06 futures are 172 points higher today than on
June 26.
Given the continued decline in U.S. crop
conditions and the predicted weather for the next 30 days, now may
be the time to consider purchasing December .58 call options.
Presently, one .58 call option can be purchased for 2.01 cents per
pound ($1005). One call option would protect the counter-cyclical
payment on 100 bales of production. To reduce the cost of this
strategy, those comfortable with options could also look at selling
calls at or near 66 cents to offset the cost of purchased options.
The cost of 58-cent call options will only
increase as the futures market approaches that price level (i.e. 58
cents). December '06 futures are currently trading at 55.18. For
questions related to commodity marketing, producers are encouraged
to contact the authors of this article. (Scott
Stiles (870) 972.2481 or
Rob Hogan (870) 526.2199 ext. 108)
Upcoming Meetings
2006 Field Days/Crop Tours
- August 10 - Clay
County
- August 24 - Lon Mann
CRS at Marianna
- August 25 - Jefferson
County
- August 31 - Judd
Hill at Judd Hill
2006 County IPM Meetings
| Date |
County |
Location |
Time |
| August 8, 2006 |
Woodruff/Monroe |
Cotton Plant Gin |
Noon -
1:00 p.m. |
Back to
Arkansas Weekly Crop Report | 
