Southwest Michigan fruit update – July 8, 2026
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EmailSummer cover programs, harvest transitions and second-generation insect activity shape this week’s orchard priorities.
Tree fruit updates
The earliest cultivars of peaches and nectarines in the region were recently or are currently being harvested, including Desiree, PF-1, Veeblush and Earlystar. Progression of harvest is coming along quickly, with many varieties ripening approximately one week sooner than last year. Approximate harvest dates based on growing degree days is available through the peach ripening model on Enviroweather.
Damage from second generation oriental fruit moth has been showing up on fruit for the past two weeks. Continue monitoring fruit for entries, gum, flagging shoots and edge-related injury. Control of this generation should be timed to the beginning of second-generation egg hatch, using the local biofix and Enviroweather degree-day model. Adult oriental fruit moth catches are increasing at the Trevor Nichols Research Center in Fennville and at the Southwest Michigan Research Center in Benton Harbor, indicating flight and egg laying are continuing. Where treatment is necessary this week, select a product with activity against oriental fruit moth eggs or newly hatched larvae, such as an effective diamide, spinosyn or acetamiprid product. Consider previous insecticide use, rotate IRAC groups and account for the preharvest interval of the cultivar being treated.
Peach brown rot management approaching harvest. For cultivars approaching harvest over the next several weeks, brown rot management should now move into the foreground. Fruit become increasingly susceptible as they mature, accumulate sugar and soften. Risk rises rapidly during warm, humid weather and rain, particularly when fruit surfaces remain wet. Showers and thunderstorms are forecast for southwest Michigan on Thursday and scattered rain may continue into Friday, so blocks with early cultivars should be protected before this wetting period rather than treated after infection has occurred.
Begin evaluating brown rot programs approximately three weeks before the expected harvest of each cultivar. This timing will differ substantially among cultivars within the same farm, so organize management by harvest sequence rather than applying the same program across the entire peach block. Use cultivar maturity, background color, fruit firmness, harvest prediction tools and recent weather conditions to determine which blocks are entering the high-risk period. Fruit with declining green background color, increasing aroma and rapidly decreasing firmness should be treated as biologically close to harvest even when the projected calendar date remains several days away.
Scout this week for small brown lesions, soft fruit and gray-brown sporulation, especially around split pits, oriental fruit moth entries, bird pecks, limb rubs and fruit-to-fruit contact points. Pay particular attention to orchard edges and heavily cropped limbs where fruit contact and insect injury may be greater. Remove visibly rotting, damaged or overripe fruit where practical. Each sporulating fruit can become a major source of inoculum, and additional infections may already be developing before symptoms become visible. Once an individual fruit is infected, fungicides cannot eliminate that infection; applications protect the remaining healthy fruit.
Maintain thorough fruit coverage and place the strongest brown rot materials in the highest-risk blocks and closest to harvest. Rotate FRAC groups and consider the active ingredients within premix products rather than rotating only trade names. Avoid repeated dependence on a single fungicide class, particularly in orchards with a history of brown rot control failures. When selecting a product, take into account the expected residual activity, rainfall, resistance-management restrictions and the number of applications already made from each FRAC group. Carefully check product-specific preharvest intervals as early cultivars begin to come off, and coordinate fungicide timing with the actual picking schedule. Tightening harvest intervals and avoiding the accumulation of overripe fruit can be as important as shortening spray intervals during periods of high disease pressure.
Plums are in the cover-spray period, with the first harvest still a few weeks out. Bacterial spot is showing up on leaves and fruit.
Cherry harvest is complete in southwest Michigan. Priorities for both tart and sweet cherry should shift toward retaining healthy foliage, maintaining adequate soil moisture, assessing tree condition and preparing orchards for next season.
Continue irrigation where soils are drying. Harvest removes the crop, but the canopy remains physiologically active and is still supporting root growth, reserve accumulation and development of flower buds for 2027. Avoid allowing trees, especially young plantings, trees on dwarfing rootstocks and heavily cropped blocks, to enter prolonged water stress. At the same time, avoid late-season practices that stimulate excessive succulent growth and delay cold acclimation.
Postharvest is also a useful period to evaluate bacterial canker, winter injury, declining scaffolds and weak or excessively dense canopy areas. Sweet cherry pruning and removal of cankered or damaged wood are best performed during a stretch of warm, dry weather, when pruning wounds dry and callus quickly and conditions are less favorable for bacterial canker infection. Avoid pruning immediately before rain or when trees are severely drought-stressed.
Scout young and nonbearing trees for Japanese beetles, mites, aphids and other pests capable of causing substantial defoliation. Mature trees can tolerate some feeding after harvest, so treatment decisions should be based on the amount of foliage being lost rather than the presence of insects alone. Remove remaining fruit and mummified cherries where practical, record blocks with serious brown rot, leaf spot or canker pressure, and use those observations when developing pruning, sanitation and disease-management plans for next season.
This will be the last week cherries will be included in the scouting report.
Apple blocks are now in the summer cover-spray period. Clean blocks can move into a lower-risk maintenance program, while blocks with visible scab lesions should remain protected against secondary scab during warm rains and extended leaf wetness. Captan remains a common cover material but does not control powdery mildew, so susceptible cultivars or blocks with active mildew may need additional activity.
Codling moth catch is declining at the Southwest Michigan Research and Extension Center, and blocks are past first-generation larvicidal timing. Continue using local trap catch, biofix and treatment history to guide decisions, and reset cumulative trap counts after an application. During summer covers, rotate modes of action, maintain good coverage as fruit size increases and avoid unnecessary broad-spectrum insecticides where mite and beneficial-insect balance remains stable.
Pears. Plum curculio activity has largely wound down, and primary pear scab is moving out of its main risk window. Clean blocks can ease into a maintenance program, while blocks with visible scab lesions should remain protected during wetting events because secondary scab can still spread on fruit and foliage.
Pear psylla should be the main insect focus this week. Scout new shoot growth for adults, eggs, young nymphs and early honeydew. Summer psylla problems are much easier to prevent than to clean up after colonies are established. Avoid unnecessary broad-spectrum disruption where possible, since conserving predators can help slow psylla buildup through the summer.
Small fruit updates
Grape bloom is over in southwest Michigan. Juice grapes and early hybrids are at berry touch. Some tight clustered varieties are beginning bunch closure. Many vinifera are near pea berry size. Rose chafer and Japanese beetle are out. Grape berry moth catches doubled since last week at the Trevor Nichols Research Center.
Blueberries are being harvested. Damage from flower thrips has been observed in various fields across the region. Cranberry fruitworm have been caught at the Trevor Nichols Research Center, and the catch remains steady from last week. Blueberry maggot is down from last week, as are spotted wing drosophila. Both cherry fruitworm and thrips catches are up from last week. Japanese beetle has been caught in the Fennville area.
Strawberry season is closing and growers are thinking about renovation. Check out this article about renovation.
Upcoming meetings
Save the date for the Blueberry Field Day on Sept. 9 at the Trevor Nichols Research Center in Fennville, Michigan.
Thank you to everyone who participated in this year’s Tuesday Night Fruit IPM meetings. We appreciate the growers, scouts, industry partners and Extension colleagues who joined us in person at the Southwest Michigan Research and Extension Center in Benton Harbor or online through Zoom.
This year’s meetings covered crop phenology, insect and disease progression, pest management updates and selected topics from Extension experts. The meetings included small fruit updates for southwest Michigan and tree fruit updates for southwest and southeast Michigan. Past meeting recordings are available online through MSU Mediaspace for those who would like to review previous sessions.
This work is supported by the Crop Protection and Pest Management Program (grant no 2024-70006-43569) from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.
