West central Michigan apple maturity report – Sept. 19, 2018

Updates on maturity status of Gala, Honeycrisp, Jonathan, Jonagold, Empire, Ambrosia, Mutsu/Crispin and Golden Delicious.

General harvest comments

Gala harvest is underway or complete at most locations in the region, although a few late sites close to the lake are just getting started. Honeycrisp harvest is underway, and many growers are going to be hustling to get through this variety as quickly as possible since it has matured more rapidly than expected. Jonathan is mature and can be harvested when growers get to it. Mutsu/Crispin, Jonagold, Empire and Golden Delicious still need a week or more to mature.

A little bit of sooty blotch and flyspeck has showed up in the last week, but I have not seen anything too bad yet. The same is true for fruit rots such as bitter rot. A little can be found here and there, but it is not widespread. Orchards have had boxes out in rows for over a week in most places, so the spray season for many operations is over.

Brown marmorated stink bug injury was observed on fruits from several locations this week on several varieties. While trap catches and stink bug activity in proximity to traps still has not been observed much in our region, this pest does seem to be making occasional presence felt to some degree at a few sites. Trap activity at previously documented hot spots in Grand Rapids, Michigan, and up in the Traverse City, Michigan, area has picked up in the past several days, indicating this pest is starting to be highly attracted to apples at this time.

If you suspect you have an issue, consider an edge spray to combat this pest, particularly on sites that border soybean fields or woods. Conventional wisdom over the past couple of years has been that the damage is typically experienced on yellow varieties, but I saw it on a widespread of varieties this week. It just tends to be easier to see without peeling the skin back on yellow varieties I have seen it present on Gala, Honeycrisp, Jonagold, Empire, and Golden Delicious.

Individual variety 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: scale 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: scale 1-4; 1 is no watercore and 4 is severe watercore.
  • Bleeding: scale 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.

Gala harvest will be concluded at most sites in the region by the end of the week, and many have already finished up. The data in this week’s table is from two late sites in Mason and Oceana county – the rest of the sites that have been included in the reports over the past month were not included this week because fruit was already harvested or harvest was underway as of Monday. Fruits from the two sites sampled this week will be ready to pick by the end of this week. This will be the last week of Gala maturity sampling.

Regional summary data for Gala, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Aug. 20

25.5 (22-29)

1.05 (1-2)

10.75 (9-12)

Aug. 27

23 (19-30)

1.7 (1-4)

11.6 (10-13)

Sept. 3

21.31 (18-27)

2.03 (1-5)

12.54 (10.5-14.5)

Sept. 10

20.54 (17-25)

3.02 (1-7)

12.97 (11-15)

Sept. 17

20.41 (17-23)

2.55 (1-6)

12.96 (11-16)

 

Pacific Gala, Benona area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

65

1

1

19.8

19.1

12.2

1

0

2

2

35

1

3

22.1

21.7

13.1

1

0

1

3

40

2

1

17.1

17.4

12.6

1

0

5

4

55

1

2

23

21.4

12.7

1

0

1

5

45

1

2

22

22.2

12.1

1

0

1

6

55

1

1

20.2

20.1

13.3

1

0

3

7

60

1

2

17.7

16.1

13.5

1

0

4

8

85

1

2

22.3

22.2

12.5

1

0

1

9

70

1

3

17.1

16.9

12.7

1

0

4

10

75

1

2

22.4

20

14

1

0

2

Ave.

58.5

1.1

1.9

20.37

19.71

12.87

1

0

2.4

 

Un-named strain, Ludington area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

1

2

22.2

19.1

14.2

1

0

2

2

80

1

2

21.8

26.6

14.5

1

0

2

3

75

1

2

19.1

18.8

16

1

0

6

4

75

1

1

20.1

20.1

12.3

1

0

2

5

70

1

2

26.2

24.6

13.9

1

0

3

6

75

1

2

16.1

20.3

11.6

1

0

3

7

70

1

2

22.1

22.4

12.3

1

0

2

8

65

1

1

20.1

16.7

12.8

1

0

3

9

55

1

1

18.2

19.9

11.7

1

0

2

10

65

1

2

20.3

20.7

11.2

1

0

2

Ave.

70.5

1

1.7

20.62

20.92

13.05

1

0

2.7

Honeycrisp was sampled for the fourth time this week. This variety has matured rapidly this season, with many growers struggling to get finished with earlier varieties and get crews rolling in these orchards. A lot of ReTain has gone out in the last couple of weeks in an attempt to stick fruit on to trees and hang on to firmness. Most orchards sampled this week are not yet considered over-mature, but this variety will likely be heading in that direction by the end of the week at current pace and some orchards have already moved in to the range of over-maturity. This heat will mean that a lot of hot fruit undergoing heavy respiration is going to be headed for storage rooms this week. Honeycrisp is very sensitive to injury from high CO2 in storage, so do your best to cool off fruit prior to rooming it and using a half skid of lime to combat rising CO2 levels in chambers.

Regional summary data for Honeycrisp, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Aug. 27

16.8 (15-21)

1.3 (1-3)

11.4 (10-12.5)

Sept. 3

16.13 (15-19)

2.07 (1-6)

11.84 (10-13)

Sept. 10

13.94 (10.5-16)

4.07 (2-7)

11.89 (10-14)

Sept. 17

13.67 (10.5-16.5)

5.8 (3-8)

12.84 (10.5-14.5)

 

Honeycrisp, Elbridge area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

1

3

15.3

16.7

12.5

 1

1

8

2

80

1

2

14.5

15

13.2

 1

1

8

3

65

1

2

13.9

12.4

12

 1

1

8

4

70

1

2

12.4

12

11.8

 1

0

8

5

85

1

2

17

20.4

12.9

 1

0

7

6

85

1

2

13

14

13.3

 1

0

8

7

90

1

2

15.8

16.3

11.5

 1

0

8

8

65

2

3

13.2

14.8

11.4

 1

0

7

9

65

2

2

16.3

16.1

13.6

 1

0

6

10

75

1

2

16.3

12

13.5

 1

0

7

Ave.

75.5

1.2

2.2

14.77

14.97

12.57

 1

0.3

7.5

 

Honeycrisp, Weare Township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

65

4

2

14.1

11.2

12.4

1

0

4

2

60

4

2

11.9

14.1

11.2

1

0

4

3

70

3

2

12.3

13.1

12.6

1

0

7

4

65

4

2

11.4

14.1

10.5

1

0

4

5

70

4

2

13

13.8

11.6

1

0

7

6

35

4

2

12.2

15.1

12.1

1

0

4

7

45

4

2

13

14.3

12.6

1

0

5

8

40

4

2

14.7

12.8

14

1

0

5

9

70

4

2

13

13

12

1

0

5

10

65

4

2

14

15.2

12.4

1

0

6

Ave.

58.5

3.9

2

12.96

13.67

12.14

1

0

5.1

 

Honeycrisp, Ludington area (site 1 of 2)

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

85

4

3

13.2

12

13.2

1

0

4

2

75

4

2

17

11.1

14

1

0

6

3

65

3

2

12.9

12.5

13.5

1

0

6

4

70

3

2

12

12

12.5

1

0

5

5

45

4

2

11.5

11.3

12.4

1

0

4

6

85

2

2

8.9

12

14.4

1

0

8

7

70

3

2

11.2

13.2

13.1

1

0

7

8

45

3

2

13.2

11.8

13

1

0

4

9

30

4

2

12.2

11.5

12

1

0

2

10

65

4

2

15

11.7

14.1

1

0

7

Ave.

63.5

3.4

2.1

12.71

11.91

13.22

1

0

5.3

 

Honeycrisp, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

65

4

2

2

12

12.2

1

0

7

2

25

4

3

12.8

15

12.2

1

0

5

3

85

4

2

14

14

13.1

1

0

5

4

35

4

2

15.2

16.1

12.3

1

0

3

5

85

3

2

13.5

17

13.5

1

0

5

6

75

3

2

15.5

17.5

13.6

1

0

3

7

55

4

2

13.2

14.3

13.8

1

0

6

8

85

3

3

14.3

15.1

12.4

1

0

3

9

75

2

2

13.1

12.7

12.7

1

0

7

10

30

4

2

14

15.2

12.3

1

0

2

Ave.

61.5

3.5

2.2

12.76

14.89

12.81

1

0

4.6

 

Honeycrisp, Clay Banks area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

40

2

2

13.8

15.2

14.1

1

0

6

2

55

2

2

14

15.2

14.6

1

0

6

3

35

3

2

14.5

13

14.4

1

0

6

4

45

2

2

13

14.2

12.6

1

0

6

5

50

3

3

16.2

13.8

14.6

1

0

4

6

45

3

2

12.1

13.2

13.5

1

0

6

7

65

2

2

13.2

11.9

13.1

1

0

6

8

70

2

2

14.2

14.4

14.7

1

0

6

9

60

1

3

13.3

13

12.9

1

0

6

10

65

2

2

13

13.9

11.7

1

0

6

Ave.

53

2.2

2.2

13.73

13.78

13.62

1

0

5.8

 

Honeycrisp, Mears area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

40

2

2

13.8

15.2

14

1

0

7

2

65

2

2

14

15.2

13.1

1

0

6

3

45

2

2

14.5

13

13.2

1

0

4

4

50

1

2

13

14.2

14

1

0

6

5

70

2

2

16.2

13.8

13.7

1

0

4

6

55

2

3

12.1

13.2

14.2

1

0

4

7

55

1

2

13.2

11.9

12.7

1

0

7

8

50

1

2

14.2

14.4

13.9

1

0

7

9

60

2

2

13.3

13

14

1

0

6

10

70

2

2

13

13.9

12.9

1

0

6

Ave.

56

1.7

2.1

13.73

13.78

13.57

1

0

5.7

 

Honeycrisp, Ludington area (site 2 of 2)

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

35

3

2

11.5

13.3

12.1

1

0

6

2

65

2

2

12.9

10.5

12.1

1

0

7

3

45

3

3

13

14.5

12.7

1

0

7

4

75

2

2

12.8

11

12.7

1

0

7

5

85

1

2

12.9

13.5

13

1

0

7

6

55

2

2

14

15.2

11.3

1

0

6

7

35

2

2

14

14.2

12.1

1

0

6

8

65

1

2

12.8

12.2

11.5

1

0

7

9

75

1

2

13.3

13.2

11.6

1

0

6

10

70

1

2

11.9

15.2

10.7

1

0

7

Ave.

60.5

1.8

2.1

12.91

13.28

11.98

1

0

6.6

Jonathan was sampled for the third time this week and is ready for harvest any time growers are able to get to it. It is considered mature for CA storage at a starch index of 3.5, and we were at 3.4 as of Monday, Sept. 17. Color of this variety is excellent, and size has improved quite a bit in the last two weeks. A little bit of bleeding of red color from the skin was observed this week on this variety.

Regional summary data for Jonathan, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 3

19.5 (18-23)

2.3 (2-3)

11.5 (10-13)

Sept. 10

17.77 (15-21)

2.95 (2-4)

12.11 (11-14.5)

Sept. 7

16.86 (14-21)

3.4 (3-5)

12.87 (12-15)

 

Jonathan, Ludington area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

4

1

21.3

16.7

13.1

1

0

3

2

75

4

2

17.4

17.8

13.1

1

0

3

3

65

4

1

15.1

14.1

12.7

1

0

4

4

85

3

1

11.5

14.8

12.9

1

1

5

5

90

4

2

18

17.8

12

1

1

3

6

90

4

2

17.5

18

11.9

1

2

3

7

60

4

2

17.1

16.3

13.2

1

2

3

8

85

3

2

15

19.9

11.7

1

0

3

9

75

4

2

17.7

19.7

11.7

1

0

3

10

70

3

2

19.9

15.1

14.8

1

0

4

Ave.

77

3.7

1.7

17.05

17.02

12.71

1

0.6

3.4

 

Jonathan, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

3

3

15.7

18.2

12.6

1

0

3

2

75

3

2

16.8

17.8

13.2

1

0

4

3

85

3

2

16.8

16.4

13.4

1

0

4

4

80

3

2

17.8

16.7

13

1

0

3

5

70

3

3

17.2

15.7

14

1

0

3

6

95

3

2

15

16.2

12.3

1

0

3

7

90

2

1

16.7

18.3

13.3

1

0

4

8

85

3

2

15.8

18

12

1

0

3

9

95

2

2

17.4

15.2

14

1

0

4

10

85

3

2

16.3

15.8

12.4

1

0

3

Ave.

83.5

2.8

2.1

16.55

16.83

13.02

1

0

3.4

Empire was sampled for the second time this week and is still a week or two away from maturity. It is still very starchy and green, and had barely moved ahead of last week’s measurements as of the sampling on Monday. A little bit of water core was observed on Empire this week at a couple of sites. Size is pretty good on this variety right now, and color is improving with the cooler nights.

Regional summary data for Empire, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 10

17.68 (15-20)

2.05 (2-3)

10.67 (9-11.5)

Sept. 17

17.80 (14-22)

2.1 (2-3)

11.78 (10.5-13)

 

Empire, Ludington area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

3

1

19

15.5

13

1

0

2

2

55

2

1

16.4

20.1

10.5

1

0

2

3

75

3

1

19.8

16.6

11.5

1

0

2

4

65

3

1

16.8

16

11

1

0

2

5

75

3

2

17.4

17.3

11.3

1

0

2

6

80

3

1

16.8

16.8

11.2

1

0

2

7

65

4

1

15.2

19.2

10.3

1

0

2

8

45

3

1

17

15.5

11.3

1

0

2

9

35

2

1

16

19.4

10.8

1

0

2

10

75

3

1

17.5

16

11.9

1

0

2

Ave.

64.5

2.9

1.1

17.19

17.24

11.28

1

0

2

 

Empire, Clay-Banks area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

45

3

1

18.7

19.2

11.4

1

0

2

2

55

2

1

16.8

21.2

10.7

1

0

2

3

75

2

1

19.2

15.8

11.2

1

0

2

4

40

2

1

22

15.3

11.9

2

0

3

5

50

2

1

14.8

18.1

11.1

2

0

3

6

55

3

1

17.3

21.1

11.2

2

0

2

7

65

2

1

20.7

22

11.7

1

0

2

8

75

2

1

16.6

16.8

11

1

0

3

9

60

3

1

16

16.3

11

1

0

2

10

75

3

1

17.6

18.8

11.2

1

0

2

Ave.

59.5

2.4

1

17.97

18.46

11.24

1.3

0

2.3

 

Empire, Hart area                   

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

85

3

1

17.2

16

12.1

1

0

2

2

35

4

1

19.3

22.2

12.5

1

0

2

3

65

4

1

19.4

17

13.1

1

0

2

4

55

4

1

14.4

15.4

13.1

1

0

2

5

75

2

2

18.3

18.2

12.4

1

0

2

6

70

3

2

18

16.8

12.7

1

0

2

7

60

3

2

18.9

20

13

2

0

2

8

65

3

2

23.3

19.4

13.1

1

0

2

9

70

3

1

15.3

18.3

13.3

1

0

2

10

45

3

1

15.1

16.8

12.9

1

0

2

Ave.

62.5

3.2

1.4

17.92

18.01

12.82

1.1

0

2

Jonagold was sampled for the second time this week, and has taken a nice move forward in a week’s time. Color is variable on this variety and is dependent on site and strain. Most sites are probably another week away from optimal harvest timing. Jonagold is considered mature for CA storage at a starch index of 3.5 and not considered over-mature until 5.5. Based on this week’s numbers, I expect the middle to end of next week will be ideal timing for most sites to get rolling with Jonagold.

Regional summary data for Jonagold, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 10

18.86 (15.5-21)

2.2 (2-4)

12.16 (11-13.5)

Sept. 17

17.51 (14-20.5)

3.13 (2-6)

12.21 (10-13.5)

 

Jonagold, Elbridge area              

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

85

2

3

16.2

17.1

12.7

1

0

3

2

90

2

2

20.2

21.6

12.1

1

0

3

3

95

2

2

16.8

17.6

11.9

1

0

4

4

90

2

2

21.2

19.8

11.7

1

0

3

5

90

2

2

20

22

12.1

1

0

2

6

95

2

2

20.4

20.2

12.5

1

0

3

7

90

2

1

20.1

22.2

12.2

1

0

2

8

85

2

3

17.8

19.8

13

1

0

3

9

85

2

1

20.7

19.1

12.9

1

0

4

10

85

2

2

18.7

20.6

12.4

1

0

2

Ave.

89

2

2

19.21

20

12.35

1

0

2.9

 

Jonagold, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

70

3

2

16.6

16.2

13.4

1

0

2

2

65

2

3

14.2

16.8

12

1

0

3

3

75

3

1

19.4

16.8

13.1

1

0

5

4

70

3

1

18.9

15.2

12.2

1

0

2

5

80

3

1

20.5

18.4

12.6

1

0

2

6

45

4

2

15

16.1

12.1

1

0

3

7

70

4

2

14.1

16

12.2

1

0

2

8

60

4

2

16.5

16.8

11.7

1

0

2

9

65

4

2

17.1

18.3

12.2

1

0

4

10

70

4

1

15.1

17.8

11.5

1

0

2

Ave.

67

3.4

1.7

16.74

16.84

12.3

1

0

2.7

 

Jonagold, Ludington area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

0

4

1

16.7

15.7

13.2

1

0

3

2

5

4

2

14.4

16.8

12.9

1

0

4

3

5

4

2

16

14.8

11.6

1

0

4

4

10

4

2

17

15

12.8

1

0

2

5

10

4

2

16.4

15

12

1

0

3

6

0

4

2

18.2

18.4

12.6

1

0

4

7

5

4

1

14.2

15.6

11.1

1

0

5

8

5

4

1

15.3

14.8

12.2

1

0

3

9

5

4

2

17.4

17.8

11.4

1

0

4

10

0

4

2

16.8

16.1

10.2

1

0

6

Ave.

4.5

4

1.7

16.24

16

12

1

0

3.8

Ambrosia was sampled for the first time this week. This is a variety that has gathered some interest in the past couple of years for growers looking for new fresh market varieties, so I included a sample this week to get some data out there on maturity season for our region. Although we had a lot of reports during IFTA this year that Ambrosia was a Jonagold season apple, it seems to be well behind Jonagold right now. We will see what another week brings. Color on this variety is highly depended on sunlight exposure, it has a tendency to be more a yellow apple with a blush unless well exposed to light in the canopy. In spite of being pretty starchy, they eat very nicely already.

Regional summary data for Ambrosia, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 17

17.37 (15-20.5)

1.4 (1-2)

12.11 (11-14.5)

 

Ambrosia, Hart area                          

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

25

2

2

18.8

16.3

13.4

1

0

2

2

20

2

1

15.8

16.8

11.9

1

0

1

3

20

3

1

15.9

17.8

11.6

1

0

2

4

20

1

1

17

20.2

11.2

1

0

1

5

20

2

1

21.1

16.2

14.3

1

0

2

6

15

3

1

15

19.8

11.8

1

0

1

7

20

3

2

16

17.3

11.1

1

0

1

8

15

2

1

18.7

16.4

12

1

0

2

9

10

3

2

18.2

15

11.3

1

0

1

10

15

3

1

15.8

19.4

12.5

1

0

1

Ave.

18

2.4

1.3

17.23

17.52

12.11

1

0

1.4

Mutsu/Crispin was sampled for the first time this week and is at least a week or two off from harvest in the region. It is always harvested pretty green for processing, but it is still extremely starchy and needs some more time. No blister spot was observed on the samples this week. As per usual for this variety, size is excellent. The crop generally looks to be of good quality this year.

Regional summary data for Mutsu/Crispin, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 17

18.15 (17-20.5)

2

11.02 (10-12.5)

 

Mutsu/Crispin, Mears area          

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

18

4

4

18.1

18.8

10.9

1

0

2

2

0

4

2

18.8

18.7

10.4

1

0

2

3

0

4

3

17.4

17.2

10.9

1

0

2

4

0

4

2

20

17.9

10.8

1

0

2

5

0

4

2

19.8

20.2

12.4

1

0

2

6

0

4

3

18

20

10.7

1

0

2

7

0

4

3

20.8

19.2

10.6

1

0

2

8

0

4

2

20.2

18.3

10.9

1

0

2

9

0

4

3

19.2

19.1

11.1

1

0

2

10

0

4

3

18.7

19.9

10.9

1

0

2

Ave.

1.8

4

2.7

19.1

18.93

10.96

1

0

2

 

Mutsu/Crispin, Weare township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

2

17.9

16.1

12.4

1

0

2

2

5

4

2

15.1

15.8

11

1

0

2

3

5

4

2

17.7

17.2

10.5

1

0

2

4

5

4

2

17.9

19

10.4

1

0

2

5

5

4

2

16.4

15.5

11.4

1

0

2

6

5

4

3

16.4

18.1

11.6

1

0

2

7

10

4

1

20

20.4

12.4

1

0

2

8

5

4

2

19.7

16.2

11.6

1

0

2

9

0

4

2

15.5

16.8

10.5

1

0

2

10

0

4

2

17.9

16.2

10.1

1

0

2

Ave.

4.5

4

2

17.45

17.13

11.19

1

0

2

Golden Delicious was sampled for the first time this week. It is close to harvest at some early sites and will be picked early if processors want it, but most locations are about a week or more away from maturity. It is considered ready for CA storage at a starch index of 3, and most sites tested well under that mark this week. Firmness is holding fairly well at most locations. Color of Goldens is still very green at this time.

Regional summary data for Golden Delicious, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 17

17.79 (13-21)

1.72 (1-5)

12.17 (10-15)

 

Golden Delicious, Ludington area, site 1 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

3

21.8

16.7

13

1

0

1

2

0

4

3

16.5

18.2

12.4

1

0

1

3

0

4

2

19

17.7

12.3

1

0

1

4

0

4

2

16.5

18.1

12.6

1

0

2

5

0

4

2

16.2

16.3

12.1

1

0

4

6

0

4

2

17.3

16.3

12.9

1

0

2

7

0

4

4

18.7

15.7

13.1

1

0

1

8

0

4

2

19.1

19.8

13

1

0

2

9

5

4

4

16

17.3

11.7

1

0

1

10

5

4

3

18.3

22.1

13.3

1

0

2

Ave.

1.5

4

2.7

17.94

17.82

12.64

1

0

1.7

 

Golden Delicious, New Era area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

0

4

2

17.5

14

11.8

1

0

2

2

0

4

2

13.8

13.8

9.4

1

0

3

3

0

4

3

14.2

14.4

10.3

1

0

2

4

0

4

2

14.3

14.2

9.6

1

0

3

5

0

4

2

12.6

14.2

10.2

1

0

3

6

0

4

2

14

14

10.7

1

0

3

7

0

4

2

13.9

14

10.9

1

0

2

8

0

4

2

16.1

14

9.9

1

0

5

9

0

4

2

13.8

13

9.2

1

0

3

10

0

4

2

15

16.8

10.5

1

0

2

Ave.

0

4

2.1

14.52

14.24

10.25

1

0

2.8

 

Golden Delicious, Ludington area, site 2 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

3

16.1

17.8

12.8

1

0

2

2

0

4

2

17.7

21

13.1

1

0

1

3

0

3

2

19.1

21

13.1

1

0

1

4

0

3

2

21

20.2

14.1

1

0

1

5

0

3

2

19.8

19.8

13.7

1

0

1

6

5

3

2

19

20

13.7

1

0

1

7

5

4

2

22.2

23.1

12.8

1

0

1

8

5

4

2

21.2

24

13.8

1

0

2

9

0

4

2

17.1

19

13.4

1

0

1

10

0

4

2

19.4

20.3

13.6

1

0

1

Ave.

2

3.6

2.1

19.26

20.62

13.41

1

0

1.2

 

Golden Delicious, Weare township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

10

4

2

20

16.8

14.4

1

0

1

2

10

4

2

15.8

18.9

12.1

1

0

2

3

5

4

2

16.3

17

12.6

1

0

2

4

5

4

2

17.7

16.2

14.9

1

0

1

5

10

4

2

18.8

18.4

13

1

0

1

6

5

4

2

19.9

16.6

12

1

0

1

7

0

4

2

17.7

15.8

12.4

1

0

1

8

5

4

2

15.8

18

12.9

1

0

2

9

5

4

2

17.8

19.3

12.9

1

0

1

10

10

4

3

15.2

16.8

12.7

1

0

2

Ave.

6.5

4

2.1

17.5

17.38

12.99

1

0

1.4

 

Golden Delicious, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

2

19.6

18.8

14.9

1

0

1

2

5

4

2

20.2

19.8

13.5

1

0

1

3

10

4

2

18.7

21

15.7

1

0

1

4

0

4

2

15.4

16.9

13

1

0

2

5

5

4

2

22.2

22

12.7

1

0

1

6

10

4

2

22.2

22.7

13.4

1

0

1

7

5

4

2

18.9

19.6

13.7

1

0

1

8

0

4

3

15.4

16.2

12.5

1

0

2

9

0

4

2

16

15.8

12.1

1

0

2

10

5

4

2

18.6

16.1

13.2

1

0

1

Ave.

4.5

4

2.1

18.72

18.89

13.47

1

0

1.3

 

Golden Delicious, Shelby area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

2

19.2

18.9

10.7

1

0

1

2

5

4

2

19

17.8

11.1

1

0

2

3

0

4

3

17.7

18.3

9.7

1

0

2

4

0

4

4

18.3

18

9.8

1

0

2

5

0

4

2

18.9

18.6

10.6

1

0

2

6

0

4

2

17

18.8

10.6

1

0

2

7

0

4

2

18.7

16.3

10.1

1

0

2

8

0

4

3

19

17.7

10

1

0

2

9

0

4

2

19.4

19

10

1

0

2

10

0

4

2

18

17.7

10.2

1

0

2

Ave.

1

4

2.4

18.52

18.11

10.28

1

0

1.9

 

Optimal fruit firmness and starch index for various lengths of CA storage.

 

Variety

Firmness (pounds)

 Starch Index

Short CA

Medium 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

Looking for more? View Michigan State University Extension’s Apple Maturity page for regional reports throughout the state and additional resources.

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