The worst of the last week’s heat wave targeted key corn- and soybean-producing states, and though nationally conditions declined only slightly, the same can’t be said for crops in the nation’s breadbasket.

According to the USDA’s latest “Crop Progress” report, 16 percent of the top 18 corn-producing states are in poor or worse condition, up slightly from last week’s report of 14 percent. However, from Colorado to Illinois to as far north as North Dakota, corn conditions deteriorated substantially over the last week.

Currently six states have reported least 20 percent of corn in poor or very poor condition, up from 4 states reported in the Aug. 26 report. Kansas continues its reign with nearly one-third of corn in poor or worse condition. Colorado (26 percent), Iowa (25 percent), Missouri (27 percent), North Dakota (21 percent) and Wisconsin (24 percent) are not far behind.

Corn maturity is lagging for yet another week, with 42 percent of corn denting, down from the five-year average of 61 percent. Four percent of corn is mature, compared to 38 percent reported last year.

Soybean conditions are similar to that of corn, with several Corn Belt states reporting shifts after last week’s heat wave. In Missouri, 27 percent of soybeans are in poor to very poor condition, up 6 percentage points from last week. Wisconsin soybeans in these conditions also rose 6 percentage points to 31 percent.

The number of states reporting at least 20 percent of soybeans in poor or worse condition doubled this week to four.

Soybean maturity is closer to average, with 92 percent setting pods. This is slightly lower than both the five-year average of 96 percent and last year’s report of 98 percent.

Read the full report here.