Northeast Michigan field crop regional report – July 8, 2016
Hot weather is expected to continue, but drought-stressed crops may get some relief.
Weather and rainfall
Storms that moved through northeast Michigan late last week brought some rain to the area, but not nearly enough. At the Michigan State University Hawks Enviroweather station, only 0.35 inches of rain fell. Some isolated showers occurred Wednesday, July 6, but the Hawks station didn’t receive any measurable amount of rain in that event. Another wave of precipitation is expected today, July 8, and forecasted to bring more widespread rainfall. Skies will clear out Saturday afternoon, July 9, and remain dry through the beginning of next week. Our next chance for precipitation will be Wednesday, July 13. The NOAA 6-10 day outlook predicts near normal rainfall for the coming week, while the 8-14 day outlook suggests slightly above average precipitation chances in coming weeks.
Growing degree days (GDD)
Temperatures have been very warm this past week, with daytime highs ranging from 79 to 89 degrees Fahrenheit. Nighttime lows have been up and down, ranging from 42 to 60 F. GDD accumulations since March 1 total 2,315 base 32 F, 1,450 base 41 and 839 base 50. Most of northeast Michigan is now zero to seven calendar days ahead of the 30 year average for GDD accumulation. Exceptions to this are areas near the lakeshore which are still 3 to 7 days behind normal, and southwestern Montmorency County, which is now seven to 14 days ahead of the 30 year average. Temperatures are expected to cool off slightly today and Saturday, July 8 and July 9, as rain is expected to move in, but humidity will remain high. Hot temperatures will return for the work week ahead, with highs from 87 to 91 F through Thursday, July 14. Overnight lows are expected to range from the low- to mid-60s. Both the 6-10 and 8-14 day outlooks from NOAA are predicting above normal temperatures for the coming weeks.
Harvest of first cutting Alfalfa wrapped up over a week ago in our region, but cutting and baling of grass hay is still underway in some fields. First cutting forage yields were strong in most cases, but second cutting regrowth has been slow due to the lack of rain. A unique fungal pathogen, orchardgrass choke, was confirmed last week in an Emmet County hay field. This disease forms capsule-like stromata that prevent the plant from heading and producing seed, hence the name choke.
Winter wheat in northeast Michigan is in the early dough stage of grain development, with leaves beginning to dry down. Recent dry conditions do not appear to have reduced yield, but we may see lower test weights in this year’s crop. Fusarium head blight (FHB) is virtually nonexistent in our area this year. However, we have noticed bleached heads in many fields. These bleached heads can easily be confused with FHB, but appear in this case to be caused by other fungal pathogens like take-all that infect the base of the stem restricting the flow of water and nutrients to the developing head. A way to distinguish between FHB and other causes of bleached heads in wheat is to note the extent of bleaching on the heads and across tillers on a single plant. Bleaching caused by FHB is often restricted to only a portion of each head or a subset of heads on a plant, while other diseases terminate the entire plant early on, resulting in entirely bleached heads on every tiller that often fail to produce seed. Wheat harvest should begin in approximately three weeks.
Most Corn in northeast Michigan was taller than knee-high by the Fourth of July, despite the lack of rain. Development ranges from the V6 to V9 growth stages. Herbicide and side-dress fertilizer applications are mostly complete and the crop canopy is closing. Drought stress, stunting and associated nutrient deficiency symptoms are apparent on lighter soils and where weeds were not controlled early, but the crop still appears to be in good condition across many fields. As the plants begin to elongate, rapid growth will ensue, given that soil moisture conditions improve.
Soybean growth has been slower than normal thus far in 2016 due to dry conditions. Crop development ranges from V2 to V5 depending on planting date. We have spotted a few flowers in some stands, signaling the initiation of reproductive growth (R1). These early blossoms may be aborted if soil moisture conditions do not improve. Although flowering normally signals the cutoff of glyphosate use, herbicide applications will continue in soybean fields over the next couple of weeks. Many early herbicide passes failed to achieve acceptable levels of control, likely due to limited absorption and translocation of systemic products by weeds on droughty soils. It is critical to use full rates of adjuvants and surfactant when applying herbicides in these dry conditions.
Early planted potatoes are beginning to develop buds, and in some cases flower. Tuber initiation is also underway, with daughter tubers 0.25 to 1.5 inches in diameter. Hilling and side-dress fertilizer applications are coming to an end. Irrigation has been running anywhere it is available. The first Michigan case of late blight in 2016 was confirmed in Branch County, with the source of inoculum thought to be volunteer potatoes. Growers are encouraged to monitor late blight risk regularly and remain vigilant with application of translaminar fungicides.
Dry beans in our region have mostly reached the V2 growth stage. The crop is surprisingly resilient under dry conditions, even in the early stages of growth. Post-emergent herbicide applications are ongoing. MSU Extension has established a western bean cutworm (WBC) trap network across Presque Isle, Montmorency and Alpena counties, and will be monitoring moth flight throughout the summer. Growers interested in receiving updates on the WBC flight are asked to contact the Presque Isle County Extension office.