Northwest Michigan apple maturity report – Sept. 4, 2019
Apple harvest is later than normal this season.
General apple harvest comments
This is our first apple maturity report from northwest Michigan for the 2019 season. The later than usual trend for the 2019 season has continued and thus far is impacting apple maturity. Most growers are patiently waiting for apples to meet appropriate maturity parameters to begin the 2019 apple harvest season.
This week, we sampled one block of Gingergold and two blocks of Honeycrisp in Leelanau County. Gingergolds are gaining nice pink cheeks, but development is variable within the trees, and growers have started spot picking this variety. Honeycrisp need more time before they are ready for picking. Both varieties are very firm at roughly 20 pounds. Overall, apple quality looks good with the exception of some areas that have the remnants of hail damage from storms in late July and some Honeycrisp blocks with bitter pit showing up where fruit set is lighter and/or variable.
Apple pest management programs are starting to wind down, but some late season pest are still active in the region. At the Northwest Michigan Horticulture Research Center, we are catching apple maggot flies on our baited red spheres as well as codling moth and obliquebanded leafrollers in pheromone baited delta traps. Oriental fruit moths in traps have also been reported, although we have not detected this pest at the station. San Jose scale crawlers are also active, and we have had reports of this pest showing up on fruit in commercial blocks.
We have not yet detected brown marmorated stink bug in traps in orchards this season, but this pest has been detected in residential areas. Over the Labor Day weekend, a fourth instar nymph was found on a Zinnia in Leelanau County. Thus far, brown marmorated stink bug numbers across the state have been lower than in recent years, but whether numbers will continue to be low is unknown.
After several weeks without significant precipitation, northwest Michigan received some much-needed rain on Monday, Sept. 2, with accumulations between nearly a quarter of an inch to 1.2 inch. This weather also brought windy conditions to the region. Sunny days and cooler nights are in the forecast which will continue to improve fruit color.
Apple maturity in northwest Michigan for apple collected on Oct. 2 | ||||
---|---|---|---|---|
Variety |
Firmness lbs. (range) |
Starch (range) |
Brix |
Color % |
Gingergold |
20.3 |
1 |
11.9 |
14.5 |
Honeycrisp |
19.6 (19.2-20.0) |
1 |
10.8 |
50.5 |
Suggested firmness and starch index levels for long-term and shorter-term controlled atmosphere (CA) storage by variety. | |||||
---|---|---|---|---|---|
Variety |
Firmness (pounds)* |
Starch Index* | |||
Short CA |
Mid-CA |
Long CA |
Mature |
Over mature | |
McIntosh |
14 |
15 |
16 |
5 |
7 |
Gala |
16 |
17 |
18 |
3 |
6 |
Honeycrisp |
15 |
16 |
17 |
3.5 |
7 |
Empire |
14 |
15 |
16 |
3.5 |
6 |
Early Fuji |
16 |
17 |
18 |
3 |
7 |
Jonagold |
15 |
16 |
17 |
3.5 |
5.5 |
Jonathan |
14 |
15 |
16 |
3.5 |
5.5 |
Golden Delicious |
15 |
16 |
17 |
3 |
6.5 |
Red Delicious |
16 |
17 |
18 |
2.5 |
6 |
Idared |
14 |
15 |
16 |
3.5 |
6 |
Fuji |
16 |
17 |
18 |
3 |
7 |
Rome |
15 |
16 |
18 |
3 |
5.5 |