West central Michigan tree fruit update – July 15, 2025
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EmailCherry harvest is in full swing, and apricots are being harvested.
Weather update
This week began with high temperatures in the 80s and lows in the upper 50s and low 60s in west central and Grand Rapids, Michigan, regions. Fruit development is advancing well, and sweet and tart cherry harvest is in full swing (Figure 1).
High temperatures across both regions are forecasted to be in the 80s for the next two days with lows in the 60s. There was some rain that came across the west central regions on July 11 and 12, and more rain is in the forecast for this week for Wednesday night, July 16, into Thursday. Conditions are still very dry. Based on the Hart Enviroweather station for July 14, current degree-day (DD) accumulation is 1851 DD42 and 1158 DD50. For the Sparta Enviroweather station, current DD accumulation is 2098 DD42 and 1357 DD50.
Weather data was gathered from Enviroweather.
Over the past week, some rain fell across the regions. Hart received 0.08 inches of rain July 11 and 0.10 inches July 12. Sparta received 0.07 inches of rain July 11. Soil conditions will continue to be dry, especially for the west central region. With high temperatures and low soil moisture content, trees may easily become water stressed and will need irrigation again this week.
At the Hart Enviroweather station on July 14, maximum soil temperature were 84.7 degrees Fahrenheit at 2 inches and 80.6 F at 4 inches, up slightly from last week. Maximum soil moisture on July 14 is 3.5% at 4 inches and 2.1% at 20 inches, which is very dry. Soil moisture has been gradually declining, even with short periods of rainfall. Shallow soil has more soil moisture now than the deeper soil as shown by the Enviroweather sensors. This means that the deeper soil water is not being replenished by natural rainfall. This could cause significant water stress for apple, especially for dwarfing rootstocks. As tree fruit get closer to harvest as well, low soil moisture could impact final fruit size and quality.
For the Sparta Enviroweather station on July 14, maximum soil temperature was 93.1 F at 2 inches and 87.4 F at 4 inches. Maximum soil moisture is 48.2% at 0-12 inches and 55.8% at 12-24 inches, slightly drier than last week. Irrigation is needed in both regions, particularly for young trees. Based on the weather forecast, precipitation will be minimal over the next few weeks, and irrigation will be needed in both regions.
More information and reports on normal weather conditions and departures from normal can be found on the NOAA Climate Prediction Center website, NOAA U.S. Climate Normals website, NOAA Climate Normals Quick Access Page (which may be searched by region).
Crop update
Apple varieties in Oceana County are sizing well, and the crop load is becoming more evident. Some orchard blocks of Honeycrisp, Evercrisp and Fuji may have lighter crop loads this year than a normal year. Growers are hand thinning to manage crop load and tying trees to train them to trellis wire. With rains this week, there will be risk for summer diseases such as fly speck and sooty blotch in apple and any secondary scab that is present in orchards.
Sweet and tart cherries are being harvested for fresh and processing markets. Populations of spotted wing drosophila continue to be fairly moderate in our region, and trap counts are lower this week than in the past. Once fruit are ripe, spotted wing drosophila are more attractive to fruit than to lures in traps. With rain coming, spray intervals may need to be tightened up to keep fruit protected again spotted wing drosophila.
There has been some brown rot observed over the past week in sweet and tart cherry. Since fruit are mature, they are very susceptible to brown rot. Continue protecting leaves from cherry leaf spot. The pressure has not been very high this year so far, but infection risk is still occurring with rain events and extended periods of leaf wetness (generally 5-6 hours depending on the temperature). Some cracking was observed last week due to rain and cloudy, humid conditions. Fruit cracking increases susceptibility to brown rot and creates an easy opening for fungi to get into the fruit. If you have fruit cracking, be sure to protect against brown rot.
Peaches are differentiating by size, and pits are hardening for some peach varieties. Growers are hand thinning peaches in the region. A general rule of thumb is to leave an average of 6 to 8 inches between fruit (the larger spacing for earlier or hard-to-size varieties). Thinning for processing peaches is generally 4-5 inches apart. As peaches approach maturity, they will be more susceptible to brown rot infection. Japanese beetle were observed feeding on leaves of peaches this week. Scout blocks to manage Japanese beetle and treat where populations are high.
Apricots are growing steadily and are ready for harvest this week. Color and flavor is excellent this year.
Plums have a good set for European and Japanese varieties, and hand thinning has been done in some orchards. Some plum curculio larvae were found in fruit this week. Infested fruit had advanced ripening and were easily seen compared to uninfested fruit. Check plum blocks to observe plum curculio pressure to make adjustments if needed for next season.
Pear fruitlets are growing steadily. Pear psylla populations have been observed across the region, and nymph feeding is causing black leaves known as psylla scorch. This type of damage is particularly common in sunny, dry conditions. The sticky waste excreted by nymphs, called honeydew, is also a good medium for sooty mold growth on the surface of leaves and fruit.
Pest updates
In Oceana County, no lesser apple worm were trapped this week. Oriental fruit moth was trapped with an average of two moths per trap. An average of one obliquebanded leafroller adult was caught per trap. Dogwood borer counts were three adults per trap. Codling moth counts were low this week with one codling moth trapped at one farm in Oceana County.
American plum borer, lesser peachtree borer and greater peachtree borer were not trapped at the West Michigan Research and Extension Center.
Spotted wind drosophila were trapped again this week in the west central region with an average of 26 per trap. At this time in the growing season, cherries are much more attractive than the spotted wing drosophila lures. While trap numbers may decline, spotted wing drosophila are still active and ready to infest mature fruit. With moderately warm temperatures, high humidity and recent rains, conditions for spotted wing drosophila development are very good.
To manage spotted wing drosophila closer to harvest, products like Exirel and Mustang Maxx are effective and have short pre-harvest intervals. Information on insecticide efficacy and rainfastness can be found in “Rainfast characteristics of insecticides on fruit” by Michigan State University Extension. No evidence of spotted wing drosophila resistance to pesticides has been found, but it is important to rotate chemistries to manage resistance. Focus on managing adults with excellent coverage, full covers and tightening spray intervals if populations build. A minimum of seven-day spray intervals under dry conditions is recommended with tighter intervals following a rain or other wetting event if needed.
Remember that trap counts are not necessarily an indicator of fruit infestation, especially as fruit mature. It is important to sample fruit to monitor if larvae are present in fruit. A video for larvae testing in fruit can be found at “How-to guide: Larval sampling in cherries to determine spotted wing drosophila infestation.” More information about spotted wing drosophila management can be found in “Managing Spotted Wing Drosophila in Michigan Cherry.”
In Sparta, codling moth was trapped at 13 moths per trap, and 55 oriental fruit moth were trapped, which was a sharp decline from last week. Obliquebanded leafroller adults were also observed with four moths per trap. Apple maggot has not been trapped.
For more information about regional reports, please visit the Michigan State University Extension website.
