West central Michigan tree fruit update – April 4, 2023
Print
EmailWarm weather this week is leading to changes in phenology for tree fruit in the west central region.
After a mild winter with temperatures generally above normal, March was cooler than normal which kept trees dormant. A warmup this week is expected to lead to changes in tree phenology and bud break for some tree fruit varieties in west central Michigan. Warm temperatures increased growing degree days (GDD) base 42 by 20 units over the last week. Based on the Hart Enviroweather station as of April 3, 38.4 GDD42 and 5.6 GDD50 are reported in Michigan State University’s Enviroweather.
High temperatures are predicted to be in the 60s Fahrenheit on Wednesday in Hart. Cooler temperatures are predicted later in the week with highs in the 40s and 50s F and lows in the upper 20s and low 30s F.
On April 3, storms brought heavy rain over night to some areas of Oceana County. Another storm is predicted to bring rain on April 4 and 5 this week. Fields are very wet, and growers may need to wait to plant trees until soil becomes less saturated.
Growers will need to watch weather and monitor soil conditions as they continue to work on orchard tasks such as applying dormant sprays, pulling out old orchard blocks, finishing dormant pruning and preparing for planting new trees.
Weather data was gathered from MSU Enviroweather. You can find a full weather update from Jeff Andresen, MSU climatologist, here: Agricultural Weather Update - April 4, 2023.
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) and Midwest Regional Climate Center website.
At warmer sites, some bud development is occurring, but the movement is slow (Figure 1). Growers will have a few more days to prepare for bud break for early tree fruit varieties.
Crop update
Apple varieties in Oceana County range from dormant to silver tip. Early varieties such as Zestar and Idared are showing signs of bud swell and silver tip, but most buds remain dormant in the region for varieties like Gala, Jonagold and Honeycrisp. As a reminder, silver tip in apple is 101 GDD base 42 F for McIntosh based on over 30 years of observation from Sparta, MI. Other apple varieties will be ahead or behind McIntosh. Hart is at 38.4 GDD base 42 F.
Tart and sweet cherry buds range from dormant to bud swell. If growers have not been able to get out in the field yet, there is still time to apply dormant or delayed dormant applications of oil or copper sprays to manage bacterial canker and early pests such as mites or scale.
Early peaches are showing signs of swelling and side green. Venture peach buds remain dormant at the West Central Michigan Research and Extension Center in Hart, MI. If growers have not already applied a spray for peach leaf curl, an application for final spring dormant sprays using copper products for management of peach leaf curl and bacterial canker is warranted in the next week.
Some plums and apricots are showing signs of bud swell side green.
Pear varieties are dormant or at bud swell. Dormant applications of oil can still be applied to help suppress psylla and San Jose scale populations.
Pest and disease update
With warmer conditions, pest and disease activity will begin shortly in west central area orchards. Pear psylla adults and eggs were observed at the West Central Michigan Research and Extension Center on April 3.
I will be regularly monitoring common orchard pests and initial apple scab infections periods over the coming weeks. The trapline at Trevor Nichols Research Center in Fennville, MI, trapped an average of two adult green fruitworm this week, but green fruitworm is not a major pest in our area.
If you have not applied dormant sprays such as oil or copper, do so shortly. No disease concerns have been reported for our region.
Pests to start thinking about include:
- Black stem borer
- Green fruitworm
- Pear psylla
- Redbanded leafroller
- Spotted tentiform leafminer
- Obliquebanded leafroller
- Climbing cutworms
- San Jose scale
- European red mite
For more information about regional reports, please visit the Michigan State University Extension website.
