This week finds Iowa just slightly above the seasonal average in degree day accumulations. The lack of rainfall in many parts of Iowa has been a recent topic of discussion.
Posted here are the precipitation deficits by crop reporting district from May 1 through June 11. With the exception of northeast and east central Iowa, it has been a dry start to the growing season. The question, "how critical are the current deficits to the growing crop?" is best answered, "it depends." Row crop performance is not driven so much by precipitation alone, but by moisture available to roots. For much of the state, we entered the season with pretty good subsoil moisture. However, the longer we stay dry, the more demand on those moisture reserves. And remember, June is our wettest month, and June deficits make it more difficult to make up lost ground in mid- to late summer. So, although we aren't in horrible shape now, the situation does bear monitoring.
May 1 through June 11, 2006 Accumulated Base: 50 Degree Days; Moisture Deficit from May 1 through June 11.
This article originally appeared on page 176 of the IC-496(15) -- June 12, 2006 issue.