FROM AROUND THE STATE
ISSUE 6 June 11, 1998
Top soil moisture is short across most of the north central region. However, the crop condition is still in good shape with the cooler weather. Last year at this time we had a week of temperatures in the 90's that severely injured the crop. Spikelet counts of wheat that were seeded in April range from 12 to 16 which compares to 9-11 last year. The potential for good yields is there, especially if a rain comes soon.
Fields of sunflowers, soybeans and dry beans that have recently emerged have a yellow cast due to the cool weather. Fields that were injured from last week frosts are recovering slowly. There were thousands of acres of dry beans that were replanted in central McLean county due to severe frost damage. There were isolated fields of canola, barley and field peas in northern Bottineau county of canola, that were killed by the frost and reseeding had to be done.
Spraying for weeds is now the main focus. Candan thistle is the
major weed problem.
Area Extension Specialist/Cropping Systems
Crucifer flea beetle Still hearing reports of foliar applications of warrior being warranted in some parts of the region. However, flea beetle counts are starting to decline. Continue to scout critical fields in the seedling stage.
Diamondback moth Pheromone trap counts are continuing to
increase at all trap sites: Ward County (1 trap site), Renville County (2 trap sites),
Bottineau County (10 trap sites), Burke County (7 trap sites), Mountrail County (1 trap
site), McKenzie County (1 trap site), and McLean County (1 trap site). Larvae and pupae
were observed in canola fields in rosette stage this week. Larvae will continue feeding
for 3 weeks. Larvae chew on the epidermis of all plant parts but prefer the undersides of
leaves, crevices, and young buds/pods. The pupal stages is spent in an open lacework
cocoon and develops in 4-15 days depending on temperature.
Orange Blossom Wheat Midge Accumulation of growing degree
days (DD) for midge emergence has been slowed. For example, Minot accumulated an
average of 20 DD per day during May 25-31 (two weeks ago), but only an average of 9.5 DD
per day were accumulated during June 1-7 (last week of frost damage). Male midge will
start emerging at 1100 degree days and females at 1300 DD. As of June 8, 1998, the
following DD (using a base of 40°F) has accumulated: Minot, Ward County = 896; Mohall,
Renville County = 784; Bottineau, Bottineau County = 792; Towner, McHenry County = 768;
Rolla, Rollete County = 706; Columbus, Burke County = 704; and Turtle Lake, McLean County
Sunflower beetle larvae emerging! Adults have been
busy laying eggs in sunflower fields for the last couple of weeks. Eggs develop into
larvae within 8 days, so look for young larvae. Cool temperatures has slowed sunflower
plant growth which will make seedlings more susceptible to adult/larval feeding. Continue
to scout fields for the economic threshold levels: adult beetles--one to two per seedling
and larvae 10-12 per plant.
PASTURES AND FIELD CROPS
Grasshoppers!!! Reports of grasshoppers infesting the
field margins of various crops continue to increase. Remember, it is easier to kill small
(early instar) grasshoppers NOW than larger (later instars) later in the season. With the
frost and cool temperatures last week, some mortality of early instars has occurred as
well as slower development.
Janet J. Knodel
Area Extension Specialist Crop Protection
North Central Research and Extension Center
Soil moisture levels are generally less moving east to west in south-central ND. Additional rainfall would be welcome in most of the region. An area in southern Wells county received significant hail damage to crops on June 1. Late-season crop planting is nearly complete. Warm-season crop growth is very slow due to the cool temperatures. Alfalfa harvest is slowly progressing because of poor drying conditions. Air temperatures ranging from the upper 20's to the low 30's were reported June 3-7. Corn was the most commonly affected crop throughout the region with numerous reports of severely-damaged foliage. Fortunately, regrowth is expected in nearly all cases. Reports of small acreages of soybean or dry bean damaged by frost have been reported in Emmons, McIntosh, Stutsman, and Wells counties. Some injury has also been reported on alfalfa, canola, potato, and small grain.
Leaf spot disease including tan spot, Septoria, and rust in small
grain is common but at low densities. Wireworm and cutworm damage is reported from Barnes,
Eddy, Foster, LaMoure, and Wells counties. Some sunflower is being replanted because of
these insects. Infestations of Hessian fly have been found in Stutsman, Lamoure, and
Dickey counties. Also, seed corn maggot in beans was reported in LaMoure County. European
corn borer moths are currently being trapped at the Carrington Research Extension Center.
Monitoring for grasshoppers should continue especially in the southwest part of this
region. The recent adverse weather has hampered herbicide application in small grain and
allowed advanced growth of weeds not previously controlled. Canola growers are challenged
by abundant broadleaf weed growth in the crop.
Greg Endres and Jim Harbour
Area Extension Specialists
Carrington Research Extension Center