West central Michigan apple maturity report – Oct. 23, 2019

The final push is underway. Harvest will conclude on many area operations within the next several days.

General harvest comments

This will be the final report for the 2019 season, and it’s going to be a brief one. Just a few varieties are left out there at this point for sampling, and with many growers losing labor within the next seven to 10 days and just about everything having reached maturity, there’s not much decision-making that will be impacted by tests at this point; it all has to go.

Orchards are slick from all of the rain right now, many areas are nearly inaccessible. The muddy conditions and frequent rains have made for some unpleasant harvesting conditions for crews and farm managers alike, but the push has continued all the same. Forecasts indicate that, including today, Oct. 23, we are looking at getting about four days of clear skies before the next weather system brings more days of rain. Many will be done or close to done by the time the next round of rains arrives.

San Jose scale can be seen on the calyx ends of fruits in affected orchards. Generally, there seems to be less this year than last year, thanks in part to many operations targeting the pest early this spring with oil and Lorsban, as well as an uptick in early applications of oil with Esteem. Growers who want to deploy late-season San Jose scale control are reminded by the folks at Valent that an application of Esteem at 5 ounces per acre with horticultural mineral oil 1% v/v (summer or winter grade) at 200 gallons per acre with an airblast sprayer or 400 gallons per acre with mist blower can be used post-harvest to smother overwintering scale and get control for next season. The timing for this application should be after most of the leaves have fallen from the tree.

Individual variety maturity results

The scales used to rate these different metrics on these charts are as follows:

  • Background color: scale 1-4, 1 is fully yellow and 4 is fully green.
  • Russet: 1-4, 1 is no russet and 4 is severe russet.
  • Pressure: always listed in pounds, and two pressure scores are recorded for each apple tested.
  • Watercore: 0-4, 1 is no watercore and 4 is severe watercore.
  • Bleeding: 0-4, 0 is no bleeding of red color into flesh and 4 is severe bleeding of red color in to flesh.
  • Red: listed as a percentage of the whole fruit with red color.

Red Delicious

There is no data in this week’s report for this variety, as most of our test sites have been harvested already. Red Delicious is ready for harvest throughout the region in orchards that have not been gotten to it yet, and can be picked whenever time allows.

Idared

Idared harvest started last week in the region and is ongoing. Most orchards are carrying a heavy crop, and this variety is yielding extremely well for folks this season. The variety tested slightly shy of maturity as of Monday, Oct. 14, but has moved into the optimal range throughout the region. It can be harvested anywhere it has not been started already. Color is outstanding on this variety this season, but like mentioned in previous reports, we continue to see quite a bit of red color bleeding into the flesh.

Idared

Sample area

Red %

Back. color

Russet

Pressure 1

Pressure 2

Brix

Watercore

Bleed.

Starch Index

Hart

84

2

1.8

16.5

16.7

12.62

0

1.7

3.7

Ludington

80

2

2

16.6

16.2

12.1

0

1.33

3.5

EverCrisp

This variety was sampled for the fourth time this week. We will likely see the start of harvest for the variety near the end of the week, although it may be picked into November to allow time for the background color to fade towards yellow in order to improve color. Fruits are still looking on the green side but are eating much better than they were last week. If we use Fuji specs for starch index to determine maturity for this variety, it is in the early end of maturity. We saw an uptick in water core in the variety this week, as we have seen in past years closer to harvest.

EverCrisp

Sample area

Red %

Back. color

Russet

Pressure 1

Pressure 2

Brix

Watercore

Bleed.

Starch Index

Elbridge

62

2.7

2.8

22.1

23.4

14.2

1.2

0

3.6

Hart

42

3.8

1.3

19.2

18.6

13.6

1.4

0

3.2

Fuji

Much of the Fuji in the area went into bins in the second half of last week and the first half of this week. The rest can go whenever growers get to it; it is ready for picking. Fuji is considered mature for controlled atmosphere (CA) storage harvest at a starch index of 3 with suggested firmness between 16 and 18 pounds.

Fuji

Sample area

Red %

Back. color

Russet

Pressure 1

Pressure 2

Brix

Watercore

Bleed.

Starch Index

Ludington

47

3.2

1.1

17.5

18.3

14.5

0

0

3.6

 

Suggested firmness and starch index levels for long-term and shorter-term storage by variety.

Variety

Firmness (pounds)*

Starch Index*

Short CA

Mid CA

Long CA

Export CA

Mature

Over mature

Braeburn

16

17

18

 

3

7

Cortland

14

15

16

 

4

6

Empire

14

15

16

18

3.5

6

Fuji

16

17

18

 

3

7

Gala

16

17

18

 

3

6

Golden Delicious

15

16

17

 

3

6.5

Honeycrisp

15

16

17

 

3.5

7

Idared

14

15

16

 

3.5

6

Jonagold

15

16

17

 

3.5

5.5

Jonathan

14

15

16

 

3.5

5.5

McIntosh

14

15

16

 

5

7

Mutsu/Crispin

16

17

18

 

3

6

Northern Spy

16

17

18

 

3

6

Red Delicious

16

17

18

 

2.5

5

Rome

15

16

18

 

3

5.5

Spartan

17

18

19

 

4

6

Winesap

17

18

19

 

2.5

6

*Firmness is measured with a mechanical 11-mm wide probe inserted into the pared flesh of a fruit to a distance of 8 mm. Starch index is measured on equatorial cross section of an apple stained with iodine solution and rated using the Cornell University starch-iodine index chart for apples on a 1-8 scale (Predicting Harvest Date Window for Apples by Blanpied and Silsbey, Cornell Extension Bulletin 221.)

 


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