Central Michigan vegetable regional report – June 25, 2014
Warm, wet weather aids crop growth in Central Michigan this week.
Warm temperatures and rain showers have benefited nearly all crops in Central Michigan this week. Measureable rain has fallen in the region five of the last seven days with variable amounts. Most areas have received in access of 1.5 inches with some areas receiving well over 2.5 inches. According to the Michigan State University Entrican Enviro-weather station, air temperatures have ranged from 62 degrees Fahrenheit on June 20 to 83 F on June 22, with nighttime lows in the mid-50s to mid-60s. Average humidity levels have been in the low to mid-80s.
Potato planting is complete with more than 95 percent of the crop now emerged. Growth stages are variable from newly emerged to tuber set on early fields. Cultivation and hilling is complete on early planted fields while many other fields will receive first cultivation in the coming week. Colorado potato beetle adults, egg masses and larvae can be found on volunteer potatoes and potatoes not treated with insecticide, and adults can be found in a few fields that have been treated with insecticide at planting. Adult potato leafhoppers are present in low numbers.
Due to the high humidity, rain and warm temperatures, 16 disease severity values were accumulated in the past week. To calculate total severity values from your emergence date, go to the Michigan Potato Diseases late blight website and follow the disease prediction link. Michigan State University Extension advises growers to begin applying protective fungicides to emerged potatoes.
Volunteer potatoes have emerged in rotation crop fields and a few rock or cull piles. Timely control will help prevent the spread of disease later in the season.
Pickling cucumber planting continues in Gratiot and Montcalm counties. Stands generally look good with few issues to report.
Sweet corn planting is nearly complete. Early planted fields without plastic are V10 to tassel emergence. So far this season there has not been any specific insect pest that has been doing damage over the entire region, but rather creating isolated issues. Very little black cutworm larval injury has been observed despite the moth flight observed earlier in the season. Armyworm is present in some locations, but generally not in large numbers. Wildlife injury, most notably deer, geese and sandhill cranes, seem to be doing as much damage to plantings as many of the insect pests. Scouting is key to identifying pest issues early.