Greg Endres, Brandt Lemer, Marcia McMullen, Carl Bradley, Jan
Knodel, and Duane Berglund
During the 2006 growing
season, field surveys were conducted in North Dakota by the NDSU Extension Service
to identify pest presence and agronomic production factors in small grain, corn
and oilseed crops. Survey coordinators were Drs. Marcia
McMullen and Carl Bradley,
extension plant pathologists, and Dr. Jan Knodel,
extension entomologist. Carrington
Research Extension
Center staff members Brandt Lemer, summer IPM
crop scout, and Greg Endres,
area extension specialist/cropping systems conducted the surveys in 337 fields
in 12 south-central counties (Burleigh, Dickey, Eddy, Emmons, Foster, Kidder, LaMoure, Logan, McIntosh, Sheridan, Stutsman, and Wells).
Use of the survey data includes grower and ag industry education, and support for labeling of
crop protection products.
The small grain survey was conducted in south-central
North Dakota
from early June to early August primarily for leaf and head diseases. The 133
surveyed fields included 110 wheat and 23 barley fields. Diseases included in
the survey were bacterial leaf blight, barley yellow dwarf, black chaff, Cephalasporum stripe, dwarf bunt, ergot, rust (leaf, stem,
and stripe), scab (Fusarium head blight), Septoria,
smut (flag and loose), spot blotch, tan spot, and wheat streak mosaic. As an
example of generated data, the figure below illustrates the season’s summary of
tan spot percent severity across North
Dakota. The survey insect list included aphids,
cereal leaf beetle, grasshoppers, and thrips
(barley).
The canola survey was conducted during August 1-7 in eight
swathed fields in Sheridan and Wells counties. The fields were inspected for
the presence of Sclerotinia stem rot (white mold), blackleg, aster yellows, and
Alternaria. White mold was detected in 50% surveyed
fields, but field incidence was low (2-6% of plants infected). In addition, the
fields were surveyed for flea beetles and grasshoppers.
The soybean
survey was conducted in 101 fields for the Asian soybean aphid and soybean
rust. Soybean aphids were commonly found throughout the region. It is estimated
that about 60% of soybean fields in the state required treatment for this pest.
The sunflower
survey conducted in south-central North Dakota
included 67 fields visited during late June to mid August to inspect plants for
downy mildew, sunflower beetle, and seed weevil. Downy mildew was very low due
to the dry conditions. Beetle and seed weevil incidence was also low.
Corn traps (one
yellow sticky and one kairomone per field) were
placed in 28 fields during mid July and collected by early August to detect the
presence of rootworms. Low levels of Western, Northern and Southern rootworms
were collected in the region (see map below).
Also, a sunflower
field survey was conducted in September by the National Sunflower Association
in cooperation with the NDSU Extension Service. Various data were recorded
including plant population, row spacing, tillage system, estimated yield, and
presence/symptoms of weeds, insects, disease and birds. Survey coordinator was
Dr. Duane Berglund, extension agronomist. Dr. Larry Charlet, ARS sunflower entomologist,
Theresa Gross, ARS sunflower entomology technician, and Greg
Endres participated in the program
by surveying nine fields in Foster, Eddy, Wells and Sheridan counties. In these
counties, average plant population was 16,880 plants/acre
(range of 8000 to 23,500) and average yield was estimated at 1265
lb/acre (range of 710 to 1680). The majority of surveyed fields were reduced
till (56%) and in 30-inch rows (67%). The most common yield-limiting factor
(33% of fields) was drought. Disease incidence, including Sclerotinia, and
insect damage generally was low. Seed loss from blackbird feeding was noted in
44% of surveyed fields.
Maps displaying summaries of survey results by crop and pest
are available at the following website: http://www.ag.ndsu.nodak.edu/aginfo/ndipm/.
Survey details may be obtained by contacting the Carrington Center.