Excessive early-week heat likely trimmed yield prospects for reproductive summer crops, though rainy, cooler conditions by mid-week prevented further yield losses.
A continuation of the brief but intense heat wave which began on or about July 14 lingered into the early part of the week, with highs approaching or topping 40°C in key corn and sunflower areas of Russia and Ukraine through July 18.
Impacts varied considerably from region to region, largely based on planting dates and the resultant crop development stage.
In northern Ukraine and Russia’s Central District, where corn is typically planted in early to mid-May, the heat had little impact as corn was still in the vegetative stages of development.
From southern Ukraine into Russia’s Southern district — where corn is planted somewhat earlier (mean planting date is late April) — corn was in the tassel and silk stages of development when the heat arrived; as a result, corn in southern portions of the region likely suffered some loss of yield potential.
However, widespread, locally heavy showers and thunderstorms (10-80 mm) signalled the arrival of cooler weather, limiting the deleterious impacts of the heat on reproductive corn (and to lesser extent sunflowers) to 6 days or less.
While potentially harmful for summer crops, the sunny, hot weather enabled a rapid winter wheat harvest pace before the rainy weather slowed fieldwork by mid-week.
Widespread rain and near-normal temperatures maintained favorable prospects for spring wheat, while somewhat cooler conditions in Uzbekistan eased stress on flowering cotton.
With spring wheat in the heading to flowering stages of development, a soaking rainfall (10-90 mm, locally more) over northern Kazakhstan and adjacent portions of central Russia maintained good to excellent yield prospects.
Showers were somewhat lighter (less than 10 mm) in the southern Urals District, but soil moisture was in good supply for flowering spring wheat.
Farther south, the return of near-normal temperatures (daytime highs 35-40°C) in Uzbekistan reduced stress caused by last week’s heat on irrigated cotton, which continued to progress through the flowering stage of development.