Regional reports on Michigan field crops – June 7, 2012
MSU Extension educators’ pest and field crop updates for Michigan.
This week’s regional reports:
- Southwest Michigan – Bruce Mackellar
- West Central Michigan – Fred Springborn
- Central Michigan – Paul Gross
Pleasant conditions with comfortable temperatures have followed precipitation late last week and weekend. Corn and soybeans continue to grow rapidly with the favorable conditions.
Precipitation totals since May 27 averaged 1.03 inches across the region and ranged from 1.6 inches near Lawrence, Mich., to 0.43 inches near Lawton, Mich. The heaviest rainfall over the last week was in the northern portion of Van Buren County. Normal rainfall is expected in both the 6 to 10 and 8 to 14 day outlooks.
Southwest Michigan is expected to have above normal temperatures in both the 6 to 10 and 8 to 14 day outlooks. Base 50 GDDs averaged 491 GDDs base 50 since May 1. We normally accumulate around 17.4 GDDs base 50 during the next five-day period. Warmer temperatures in the forecast will push that number ahead rapidly.
Early planted corn is at V5 to V6. The race is on to complete sidedress nitrogen operations on the earliest planted fields. Weed control generally looks good on these fields. Later planted fields are V3 to V4. Soil moisture will become more critical as corn is beginning to reach higher ET rates (nearing 0.1 inches per day as we move to the V5 stage). Moisture has been adequate so far, but soil reserves may be lower than we have seen in several years across the region going into this growth stage.
Insects have not been a major issue, with relatively small acreages of corn treated for black cutworms and armyworms. With drier conditions, we should not see much for leaf diseases at this time. The most significant stand losses I have seen this year are from sandhill crane feeding damage. Growers should be on the watch for stands that become uneven in height over the next few weeks. This can be associated with white grub feeding, particularly from a relatively new pest, Asiatic garden beetles. Sidedress nitrogen application time can be a good time to assess losses from these pests. There are no rescue treatments for white grubs, but it can help you to assess options for control in future years or in the worst case scenario, replant options in heavily infested portions of fields.
Early planted soybeans are at the second trifoliate stage. Advanced fields may be pushing the third tri-foliate leaves. Soybeans generally look good across the region. Some bean leaf beetle feeding is present. I have not seen soybean aphids.
Weed control is the most serious challenge at this point. Watch soil moisture conditions and prioritize spraying fields where water stress from weeds may pose the most serious stress risks.
Wheat is in the grain fill period. Some fields have significant powdery mildew infections. Incidence of Fusarium head blight is low. There are some fields that have wheat stripe rust at low to moderate levels. We can find incidence of freeze injury to some heads from the April 27 event. Overall, for all it has been through, the crop looks pretty good.
Alfalfa has been growing well since the warm-up. Early harvested fields are 18 to 22 inches in height and beginning to push buds, so second cutting will be harvested soon. Some folks have treated for residual alfalfa weevils and potato leafhoppers. I have not seen much for leafhopper activity in the few fields I have walked. With warmer conditions on the horizon, keep an eye out and be prepared to spray re-growth for leafhoppers if the numbers in your area are on the up-swing.
An all-day drizzle with scattered thundershowers was experienced by much of the west central region last Friday (June 1) with scattered showers continuing into Saturday (June 2). The much needed moisture aided germination and emergence and brought relief to advanced crops on the lighter soils of the region. Rainfall totals were generally 0.8 to 1.25 inches in Montcalm County with lesser amounts as you moved to western portions of the region with Fremont, Mich., getting just over 0.5 inches.
High air temperatures were quite cool for the season with 50.4 degrees Fahrenheit recorded at Entrican on June 1; highs have been in the low 70s for much of the rest of the week. Low air temperatures were generally in the mid-40s. Low soil temperatures at 2 inches are in the lower to mid-50s.
Wheat is now past flowering. Just a few and very widely scattered outbreaks of armyworms are being reported as larvae are becoming bigger and more easily found. Keep in mind that large armyworm larvae (1.5 inches long) are difficult to kill with insecticides and will likely pupate soon. Cereal leaf beetle larvae, like the armyworm larvae, are getting quite large and will also be pupating soon. Lighter soils in many wheat fields will soon be getting short on soil moisture again.
Alfalfa first cutting continues and regrowth on early cut fields is progressing well. Alfalfa weevils are still present in many fields. I have found low levels of potato leafhoppers. There continues to be quite a few aster leafhoppers around.
Corn ranges from V2 to V8 with much of the crop between V4 and V6. Sidedressing is occurring as well as post-emergence herbicide applications. It is important to note that the window is rapidly closing on many post-emergence herbicide applications as corn approaches V8. Continue to keep an eye out for armyworm larvae.
Volunteer potatoes are readily found in corn fields that were potato fields last year and even in a number of fields where cull potatoes were spread. Colorado potato beetles are present and feeding on the volunteers, but will likely not control them.
Dry bean planting is underway with approximately 10 percent of the crop planted in Montcalm County.
Soybean planting is finished with generally good emergence and good stands.
Four western bean cutworm moths were caught in pheromone traps at the Montcalm County Experiment Farm this week. No armyworm or black cutworm moths were caught in pheromone traps in Montcalm County this week.
The all-day rain on June 1 brought much needed moisture to areas of the region needing rain for good crop emergence. Many farmers commented that it has been awhile since we have had that type of an all-day soaker. With the adequate soil moisture, we just need warm weather. While the season has gotten off to an early start with a warm March, the May temperatures have been generally cool. Growing degree day accumulation is considered normal.
The corn crop is planted and progressing well ahead of normal. Crop size ranges from knee high to two to three leaf corn. There has been some replanting due to poor emergence. There are reports of armyworms in several areas. Farmers are advised to scout fields regularly for this pest. Focus on field edges next to grass fields and fence rows.
Weed pressure is increasing. Consider corn height when selecting herbicides. Nitrate tests that have been taken are showing wide variability in available nitrogen.
Soybean planting has wrapped up as of last week. The rains last week will insure good emergence of the later planted fields. The early planted fields have their first and second trifoliate leaves. There has been some replanting in parts of fields due to poor emergence. Make herbicide applications in a timely manner so weeds do not compete with the beans early in the season. No reported problems at this time.
The wheat crop is turning out to be very challenging this year. Fungicide applications were completed last week. We are still finding high levels of disease in many fields. These include strip rust, powdery mildew and septoria. We are starting to see evidence of frost damage that occurred in April. Fields that were frosted have blank or severely damaged heads. There are cereal leaf beetles and reports of armyworms. Scout fields for these insect pests.
Harvest of first cutting alfalfa is wrapping up. There is still grass hay being made. Regrowth of second cutting needs to be scouted for alfalfa weevil feeding. We are seeing high numbers in many areas. There are a few farmers that are beginning to cut second cutting alfalfa. The potato leafhopper populations are beginning to grow. Scout fields for this pest.
Oats and barley are beginning to head and stands look good. Scout field for disease and insect pests. Consider fungicide applications if disease pressure is evident.
The sugarbeet crop is making good progress. There are no unusual problems being reported.
Dry bean planting will get underway when fields dry out. The crop is about 15 percent planted.
Don’t forget the 2012 MSU Weed Tours on Wednesday, June 27. For more information or to register online, visit www.msuweeds.com.