West central Michigan apple maturity report – Sept. 26, 2018

Updates on maturity status of Honeycrisp, Jonagold, Empire, Ambrosia, Mutsu/Crispin, Golden Delicious, Idared, Red Delicious, Rome and Winesap.

General harvest comments

Gala harvest is generally complete in the region, and first pick of Honeycrisp is complete at most locations. Jonathan has been picked over the last week. Jonagold is mature and growers should think about getting after this variety as soon as possible. It is ahead of both Golden Delicious and Empire, and should be picked ahead of both of those varieties when possible.

Some more sooty blotch and flyspeck has showed up in the last week, but it is not widespread. Water core and lenticel rots have also been low so far. Fruit finish generally looks very good as you look at bins. Recent cool weather has given us excellent color.

The first two brown marmorated stink bugs (BMSB) were caught in a tower trap in Hart, Michigan, this past week. This is the first time between last year and this year that our traps in the area have caught BMSB. Traps placed in Elbridge, Walkerville and New Era, Michigan, have not caught anything yet.

Injury from BMSB was again observed on fruits from several locations this week on several varieties. Most growers have not applied any sprays specifically for BMSB and this pest generally seems to be low enough that it is not an economic threat this year. However, this pest absolutely seems to be increasing in our area, so be on guard next year and consider at least edge applications for this pest.

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.

Honeycrisp was sampled for the fifth and final time this week. Most growers are through a first pick and are hoping for more color on the second pick. Fruit that was sampled this week was second pick fruit, so the numbers listed below address where your second pick is currently sitting. The sooner you can get to this the better. Cooler nights will have helped to cool fruit down heading in to storage, but remember that Honeycrisp is very sensitive to injury from high CO2 in storage, so you should be doing 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)

Sept. 24

11.57 (10-15)

7.2 (4-8)

12.01 (11-13.5)

 

Honeycrisp, Weare Township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

35

3

2

11.1

12

10.6

1

0

7

2

45

2

2

12.6

12

10.9

1

0

8

3

45

2

3

11.8

12.2

11.7

1

0

8

4

35

2

2

11.2

11.2

12.3

1

0

7

5

40

2

2

11

12

12.1

1

0

7

6

35

2

2

11.7

10.7

11.5

1

0

7

7

55

2

2

12.8

13.5

11.6

1

0

6

8

45

3

2

12

11

11.5

1

0

8

9

40

3

2

11.8

11.5

11.4

1

0

7

10

20

3

2

12.2

12.5

11.4

1

0

8

Ave.

39.5

2.4

2.1

11.82

11.86

11.5

1

0

7.3

 

Honeycrisp, Ludington area (site 1 of 2)

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

2

3

14.2

14

12.2

1

0

4

2

65

2

2

13.1

11.3

12.7

1

0

6

3

70

3

2

9.2

9.9

12.4

1

0

7

4

85

2

2

10.9

11.3

13

1

0

7

5

75

2

2

12

13.9

13.8

1

0

7

6

55

2

2

11.2

12

13.1

1

0

5

7

40

2

2

12.2

11

12.6

1

0

6

8

70

2

2

8.3

12.2

13.4

1

0

7

9

85

1

2

13

13.2

13.2

1

0

7

10

75

1

2

11

14.8

13

1

0

8

Ave.

69.5

1.9

2.1

11.51

12.36

12.94

1

0

6.4

 

Honeycrisp, Ludington area (site 2 of 2)

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

45

2

2

11

11.7

11.3

1

0

8

2

70

1

3

11.9

11.1

12.9

1

0

8

3

55

2

2

10.2

10.9

12

1

0

8

4

45

3

2

10.7

11.3

11.6

1

0

8

5

65

1

2

11.3

11.2

11.3

1

0

8

6

55

2

2

10.2

11.4

11.7

1

0

8

7

70

2

2

10.2

10.6

11.1

1

0

7

8

70

2

2

11.5

10.2

11.5

1

0

8

9

60

2

3

11

11.2

11.2

1

0

8

10

75

1

2

10.1

11

11.3

1

0

8

Ave.

61

1.8

2.2

10.81

11.06

11.59

1

0

7.9

Empire was sampled for the third time this week. Growers are anxious to get after this variety and a few have been picked already, but the variety could use a few more days so target other varieties that have moved along faster than expected such as Jonagold and hold off on Empire for a bit. Target a starch index of at least 3.5 for CA storage and firmness of 14-16 pounds. Fruit that was sampled Monday, Sept. 24, was still shy of this mark. Empire should be in better shape for harvest by the end of this week and early next week.

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)

Sept. 24

17.95 (14-21)

2.95 (2-4)

12.51 (11.3-14.6)

 

Empire, Clay-Banks area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

2

1

16.2

18.7

14.3

1

0

3

2

70

2

1

20.2

20.2

14.2

1

0

3

3

60

2

1

16.6

21.1

14.6

1

0

3

4

70

2

1

18.6

18.8

12.6

1

0

3

5

45

2

1

15.5

20.9

13

1

0

2

6

60

2

1

15.4

20.7

13.3

1

0

3

7

70

2

1

17.7

19.7

13.2

1

0

3

8

65

2

1

16.3

16.3

12.6

1

0

2

9

55

2

1

15.3

17.8

12.6

1

0

3

10

45

2

1

17

21.6

13

1

0

3

Ave.

61.5

2

1

16.88

19.58

13.34

1

0

2.8

 

Empire, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

70

3

1

17.2

14.8

12.6

1

0

3

2

60

2

1

14.1

14.1

10.4

1

0

3

3

45

2

1

18.5

17.2

11.9

1

0

3

4

65

2

1

16.1

16.8

11.1

1

0

3

5

75

2

1

17.8

17.5

11.1

1

0

3

6

80

2

1

17.1

19.2

11.1

1

0

3

7

45

2

1

19.5

17.3

12.5

1

0

3

8

65

2

2

19.5

21.6

11.3

1

0

4

9

60

2

2

21.4

17.8

12.7

1

0

3

10

65

2

2

17

19

12.1

1

0

3

Ave.

63

2.1

1.3

17.82

17.53

11.68

1

0

3.1

Jonagold was sampled for the third time this week and has taken another big move forward in a week’s time. It is mature across the region for CA storage and firmness appears to dropping to the low end of the acceptable range, so it should be picked hard this week if possible as it is considered over-mature for CA at starch index 5.5. This would be an excellent variety to send your crews in to while you wait for Empire, Golden Delicious and a couple of other varieties that are lagging behind to catch up. Color is generally very good on this variety, and size appears to be in a good range at most locations.

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)

Sept. 24

16.45 (14.5-18)

4.1 (3-7)

12.67 (10.5-14)

 

Jonagold, Elbridge area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

95

2

2

20.8

19.9

13.9

1

0

4

2

90

2

2

21

21.8

13.1

1

0

5

3

95

2

2

17.1

18.3

13

1

0

4

4

95

2

2

23.2

24

12.3

1

0

3

5

95

2

1

17.4

16.8

12.7

1

0

5

6

90

2

1

17.8

16.8

12.9

1

0

4

7

90

2

2

17.9

18.8

12.7

1

0

4

8

85

2

2

17.2

17.2

13.3

1

0

3

9

90

2

2

18.3

19.8

12.2

1

0

4

10

95

2

2

21.3

19

13

1

0

3

Ave.

92

2

1.8

19.2

19.24

12.91

1

0

3.9

 

Jonagold, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

3

2

15.2

16.9

13.6

1

0

4

2

65

4

3

15.7

16.4

14

1

0

4

3

75

4

2

18

16

14

1

0

4

4

80

4

1

14.8

14.8

13.4

1

0

4

5

80

4

2

15.2

16.1

13

1

0

5

6

75

4

1

15.8

16.3

14.1

1

0

6

7

75

4

1

19.1

18.2

13.4

1

0

2

8

80

3

1

16.2

17

13.6

1

0

3

9

85

4

2

17.8

1.7

13.4

1

0

3

10

85

4

2

16.3

14.5

14.8

1

0

4

Ave.

77.5

3.8

1.7

16.41

14.79

13.73

1

0

3.9

 

Jonagold, Ludington area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

4

2

15

13.5

11.1

1

0

7

2

10

4

2

13

16.2

12

1

0

4

3

10

4

2

16

14.4

12.7

1

0

3

4

5

4

2

15.8

13.1

10.5

1

0

6

5

5

4

3

14.3

16.3

11.6

1

0

5

6

10

4

1

15.7

15.8

11

1

0

5

7

10

4

2

13.4

15

12.1

1

0

3

8

5

4

2

14.2

14

10.6

1

0

4

9

10

4

2

13.2

14.1

11.2

1

0

4

10

5

4

2

14.6

14.1

10.3

1

0

4

Ave.

7.5

4

2

14.52

14.65

11.31

1

0

4.5

Ambrosia was sampled for the second time this week. 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 and is more in line with the maturity that I see in Red Delicious or Idared. Color on this variety is highly dependent 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.

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)

Sept. 24

16.03 (14-18)

2.2 (2-3)

11.5 (10.8-13.7)

 

Ambrosia, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

45

2

2

14.7

15

13.7

1

0

2

2

65

2

2

15.2

17

11.6

1

0

3

3

45

2

1

15.8

15.1

11.5

1

0

2

4

35

2

1

14.4

14.8

10.8

1

0

2

5

45

1

2

17.2

17.8

10.9

1

0

2

6

55

2

1

15.2

15

11

1

0

2

7

45

3

1

16.2

16.1

11.2

1

0

2

8

30

3

2

14.1

14.6

11.6

1

0

2

9

35

4

2

16

15.5

11.5

1

0

3

10

25

4

1

15.7

15.2

11.2

1

0

2

Ave.

42.5

2.5

1.5

15.45

15.61

11.5

1

0

2.2

Mutsu/Crispin was sampled for the second time this week, and is at a week or two off from maturity in the region. It will be or has already been harvested sooner than that in spite of this for processing. This variety is always harvested pretty green for processing, but it is still pretty starchy and could use some more time. It barely moved ahead of last week’s measurements in a week’s 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)

Sept. 24

16.64 (14.8-17.6)

2.1 (2-3)

10.94 (11-13)

 

Mutsu/Crispin, Mears area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

0

4

3

15.2

19.5

11.5

1

0

2

2

0

4

2

15.8

16.8

11.2

1

0

2

3

0

4

2

19.2

16.4

11.1

1

0

2

4

0

4

2

16.8

16.4

11.1

1

0

2

5

0

4

2

17.1

16.9

11

1

0

2

6

0

4

2

17

19

11.8

1

0

3

7

0

4

2

17

16.1

11.4

1

0

2

8

0

4

1

15.4

16.2

11.6

1

0

2

9

5

4

2

15.2

16.8

10.5

1

0

2

10

0

4

2

17

14.7

10.9

1

0

2

Ave.

0.5

4

2

16.57

16.88

11.21

1

0

2.1

 

Mutsu/Crispin, Weare township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

0

4

2

17.8

17

10.7

1

0

2

2

0

4

2

18.3

18

11

1

0

2

3

0

4

2

17

14.2

10.5

1

0

3

4

0

4

3

18.8

20.8

11

1

0

2

5

0

4

2

16.1

16.1

10.4

1

0

2

6

0

4

2

15.2

14.8

9.8

1

0

3

7

0

4

2

17.6

15.9

12.6

1

0

1

8

0

4

3

13.9

16.3

10.7

1

0

2

9

0

4

2

13.4

15.9

9.9

1

0

2

10

0

4

2

18.2

15.8

10

1

0

2

Ave.

0

4

2.2

16.63

16.48

10.66

1

0

2.1

Golden Delicious was sampled for the second time this week. Growers are anxious to get after this variety and some have picked a few, but similar to Empire this week this variety needs a few more days. Go after Jonagold before going after Golden Delicious. It is considered ready for CA storage at a starch index of 3, and all 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)

Sept. 24

17.42 (13.3-26.2)

2.08 (1-4)

14.24 (12.8-16.5)

 

Golden Delicious, Ludington area, site 1 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

0

3

2

14.8

17.3

12.8

1

0

2

2

0

4

2

17.8

16.8

13.5

1

0

2

3

0

3

2

15.3

16.2

13.4

1

0

1

4

0

3

2

17.2

18.4

13.3

1

0

2

5

0

3

3

16.3

14

13.9

1

0

2

6

0

3

2

23.5

18.8

14.2

1

0

2

7

0

3

3

13.3

16.1

15.1

1

0

2

8

0

3

2

19

19.7

14.6

1

0

2

9

0

3

2

18.7

17.6

14

1

0

2

10

0

3

2

15.2

17.4

13.5

1

0

2

Ave.

0

3.1

2.2

17.11

17.23

13.83

1

0

1.9

 

Golden Delicious, Ludington area, site 2 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

10

3

1

18.3

15.5

16.5

1

0

2

2

5

3

2

23.2

26.2

15.2

1

0

2

3

10

3

2

16.6

21.2

15.1

1

0

1

4

5

3

2

17.8

18.8

15.3

1

0

2

5

5

3

1

19.1

20

14.8

1

0

1

6

10

3

2

20

21.4

15.4

1

0

1

7

10

3

2

16.8

21.4

14

1

0

1

8

10

3

2

20.1

17.8

16.1

1

0

2

9

10

3

2

16.3

20

15.8

1

0

1

10

5

3

1

18.3

17.8

14.8

1

0

3

Ave.

8

3

1.7

18.65

20.01

15.3

1

0

1.6

 

Golden Delicious, Weare township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

10

3

2

18.5

16.8

15.1

1

0

2

2

10

3

2

15.8

14.9

14.3

1

0

2

3

5

3

2

15.8

17

12.8

1

0

2

4

5

3

2

15.8

17.3

13.8

1

0

2

5

5

3

1

16.1

16.4

13.8

1

0

4

6

5

4

2

15.8

17

13.3

1

0

2

7

10

3

2

16.8

15

13.3

1

0

2

8

5

3

3

16.8

15.3

13.4

1

0

2

9

10

4

2

19.4

15.5

14.8

1

0

3

10

10

3

2

16.8

14.3

15.2

1

0

2

Ave.

7.5

3.2

2

16.76

15.95

13.98

1

0

2.3

 

Golden Delicious, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

5

3

3

14

16.3

14.4

1

0

3

2

10

3

2

17.2

16.8

14.1

1

0

2

3

10

3

2

18.7

14

15.7

1

0

2

4

5

3

2

18.4

16.8

13.5

1

0

2

5

10

3

2

13.2

15

15.4

1

0

5

6

10

3

2

16.8

20

13.4

1

0

2

7

5

3

2

15.2

17.2

12.5

1

0

3

8

5

3

2

17.2

17.4

12.6

1

0

2

9

5

3

2

15.2

15.4

12.4

1

0

2

10

10

3

2

23.2

19.2

14.3

1

0

2

Ave.

7.5

3

2.1

16.91

16.81

13.83

1

0

2.5

Red Delicious was sampled for the first time this week. It is considered ready for harvest for CA storage at a starch index of 2.5 and 16-18 pounds of firmness, and is not considered over mature until a starch index of 6. Fruits sampled this week were still well shy of the early side of maturity. This variety will likely not be picked for at least two more weeks, although a few fruits may start to test in the low end of the mature range as early as next week. Firmness was a little bit low on this variety this week, so we will hope that we can hold on decent fruit firmness for another couple of weeks.

Regional summary data for Red Delicious, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 24

15.46 (13-16.5)

2.1 (1-3)

10.69 (10-11.5)

 

Red Delicious, Ludington area, site 1 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

100

NA

1

15.3

16.7

10.4

1

0

2

2

100

NA

1

13.1

16.3

9.8

1

0

2

3

100

NA

1

15

15.8

10.4

1

0

2

4

100

NA

1

13

15.8

10.4

1

0

2

5

100

NA

1

14

15

9.7

1

0

2

6

100

NA

1

15.3

16

11.4

1

0

2

7

100

NA

1

12.9

17.6

11.2

1

0

2

8

100

NA

1

14.5

14.3

10

1

0

2

9

100

NA

1

15

14.3

10.9

1

0

2

10

100

NA

1

14.6

14.7

10

1

0

2

Ave.

100

NA

1

14.27

15.65

10.42

1

0

2

 

Red Delicious, Ludington area, site 2 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

90

3

1

16.8

17.8

11.5

1

0

2

2

85

2

1

16.8

18.7

11.9

1

0

2

3

90

1

1

16.2

14.8

12.8

1

0

2

4

90

1

1

16.8

15.8

11.5

1

0

2

5

95

1

1

16.7

16.2

11.2

1

0

2

6

95

1

1

16.1

18.2

10.8

1

0

2

7

90

1

1

17.2

16.9

12.7

1

0

2

8

90

1

1

17.3

18.9

11.1

1

0

2

9

90

1

1

14.9

16.8

10.9

1

0

2

10

85

2

1

13.8

16.8

11.5

1

0

2

Ave.

90

1.4

1

16.26

17.09

11.59

1

0

2

 

Red Delicious, Shelby area, site 1 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

3

2

13.6

14

10.1

1

0

3

2

85

3

2

14.9

13

10.1

1

0

2

3

85

3

1

13.2

12.3

10.3

1

0

3

4

85

4

1

17.1

14.9

10.7

1

0

2

5

90

3

1

17.2

14.7

10.2

1

0

2

6

70

3

1

16.3

14

11

1

0

2

7

75

3

1

14

15

10.2

1

0

3

8

65

3

1

13.3

13.1

10.4

1

0

3

9

45

3

1

16.2

16.1

10.1

1

0

1

10

45

2

1

16.8

15.9

10.1

1

0

2

Ave.

72

3

1.2

15.26

14.3

10.32

1

0

2.3

 

Red Delicious, Shelby area, site 2 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

70

2

1

16.2

15.1

9.6

1

0

2

2

65

2

1

13.2

14.1

9.7

1

0

2

3

60

2

1

12.8

14

10

1

0

2

4

70

2

1

17

16.1

10.9

1

0

3

5

70

1

2

17.1

20.8

11.4

1

0

2

6

65

1

1

15.8

17.8

11.4

1

0

2

7

85

2

1

15.5

15.1

10.9

1

0

2

8

90

1

2

13.2

14.4

10.4

1

0

2

9

95

1

1

16.1

14.8

10.2

1

0

2

10

95

1

1

13.3

16.1

9.7

1

0

2

Ave.

76.5

1.5

1.2

15.02

15.83

10.42

1

0

2.1

Idared was sampled for the first time this week. This variety is still at least a couple of weeks away from the early end of CA storage maturity. Color is looking very nice on this variety, and most orchards appear to be carrying a heavy crop.

Regional summary data for Idared, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 24

16.12 (14.9-21.2)

2 (1-5)

12.14 (11.4-14.4)

 

Idared, Ludington area                                           

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

55

3

2

14.9

21.2

14.1

1

0

1

2

45

3

2

18.1

16.3

13.8

1

0

2

3

45

3

2

16.8

19.3

11.8

1

0

1

4

65

3

2

17.1

17.2

12.5

1

0

2

5

70

3

2

15.1

15

12.6

1

0

2

6

65

3

1

15

14.4

12.3

1

0

2

7

55

3

2

13.5

15.2

11.9

1

0

2

8

65

3

1

17.8

13.2

14

1

0

2

9

65

3

1

13.2

16.8

11.8

1

0

2

10

65

3

1

18.4

15.2

14.2

1

0

2

Ave.

59.5

3

1.6

15.99

16.38

12.9

1

0

1.8

 

Idared, Clay-Banks area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

3

1

16.4

18.1

13.2

1

0

2

2

85

3

3

15.7

15.6

11.9

1

0

2

3

75

3

1

14.1

17.3

10.9

1

0

2

4

65

2

2

14.6

15.9

11.2

1

0

2

5

85

3

2

17.3

14.1

12.5

1

0

2

6

65

2

2

14.9

15

10.7

1

0

2

7

70

2

2

14.2

16.4

12.3

1

0

2

8

65

3

2

15.8

16.5

11.5

1

0

2

9

55

3

1

16.3

16.7

11.4

1

0

2

10

85

3

2

16.5

17.2

11.7

1

0

2

Ave.

72.5

2.7

1.8

15.58

16.28

11.73

1

0

2

 

Idared, Hart area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

55

3

3

14.2

16.6

12.7

1

0

2

2

45

3

3

13.4

13

11.4

1

0

3

3

35

2

2

14.6

19.5

10.5

1

0

2

4

75

3

2

16.3

18.1

11.5

1

0

2

5

65

3

3

16.2

17.7

11.7

1

0

1

6

60

3

2

16

16.1

12

1

0

2

7

60

3

3

16.1

14.9

11.9

1

0

2

8

60

3

2

15.4

14.6

11.1

1

0

2

9

45

3

1

20

16

14.4

1

0

5

10

45

3

2

19.8

16.3

10.8

1

0

1

Ave.

54.5

2.9

2.3

16.2

16.28

11.8

1

0

2.2

Rome was sampled for the first time this week and is still at least a week or two away from maturity. It is considered mature for CA storage at a starch index of 3, and fruits tested this week were well shy of that mark. As is usual for this variety, firmness is excellent. No bleeding of red color from peel into flesh was observed on the variety this week.

Regional summary data for Rome, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 24

21.49 (18-25.2)

2.16 (2-3)

11.65 (10.8-13.5)

 

Rome, Shelby area, site 1 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

55

3

2

19.1

19.8

11

1

0

2

2

45

3

1

20

24.3

10.6

1

0

2

3

65

3

1

19.6

23.8

11.8

1

0

2

4

55

3

1

24.5

22.7

12.1

1

0

2

5

65

3

1

19.7

20.1

11.2

1

0

2

6

40

3

1

21.2

20.2

10.7

1

0

2

7

55

3

1

18.7

23.1

13.2

1

0

2

8

75

3

1

18.8

18.7

11.9

1

0

2

9

85

3

1

18.5

20.1

10.8

1

0

2

10

85

3

1

19.9

21

11.6

1

0

2

Ave.

62.5

3

1.1

20

21.38

11.49

1

0

2

 

Rome, Shelby area, site 2 of 2

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

65

4

1

21.2

20.1

12.8

1

0

3

2

65

4

1

24

20.8

11.9

1

0

3

3

35

4

1

18.4

20.8

11.7

1

0

2

4

55

4

1

18.3

17.3

11.9

1

0

2

5

55

4

1

20.2

20.5

12.5

1

0

2

6

45

4

1

20.2

24.8

11.7

1

0

2

7

45

4

1

20.4

23.7

11.9

1

0

2

8

65

4

1

26.3

23.1

13.1

1

0

3

9

60

4

1

19.2

22

11.6

1

0

2

10

45

4

1

19.6

19.2

13.4

1

0

2

Ave.

53.5

4

1

20.78

21.23

12.25

1

0

2.3

 

Rome, Mears area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

95

4

1

21.3

20.2

11.4

1

0

3

2

55

4

1

23.7

25

10.8

1

0

2

3

85

4

1

23.2

22.4

11.4

1

0

2

4

75

4

1

20.2

20.4

10.6

1

0

2

5

65

4

1

25.2

24.9

11.3

1

0

3

6

65

4

1

22

19.9

10.8

1

0

2

7

70

4

1

20

23.2

10.8

1

0

2

8

85

4

1

27.9

26.3

11.7

1

0

2

9

85

4

1

21.2

21.5

11.6

1

0

2

10

70

4

1

22.8

24.7

11.9

1

0

2

Ave.

75

4

1

22.75

22.85

11.23

1

0

2.2

 Winesap was sampled for the first time this week, and is still hard, green and starchy. It is at least two weeks from maturity.

Regional summary data for Winesap, west central MI 2018

Sample date

Firmness lbs. (range)

Starch index (range)

Brix % (range)

Sept. 24

16.61 (14.1-19)

2

9.44 (8.5-11.1)

 

Rome, Weare township area

Fruit No.

Red (%)

Background color

Russet

Pressure 1

Pressure 2

Brix (%)

Watercore

Bleeding

Starch index

1

75

4

1

15.9

14.3

11.1

1

0

2

2

45

4

2

19

15.3

9.4

1

0

2

3

45

4

2

17

15.4

9.1

1

0

2

4

65

4

2

18.8

18.8

9.5

1

0

2

5

35

4

2

14.5

14.1

8.8

1

0

2

6

45

4

1

15.3

16.3

9.6

1

0

2

7

55

4

2

14.6

15.4

9.6

1

0

2

8

45

4

1

19.2

18.3

9.8

1

0

2

9

65

4

2

19.3

18.1

9

1

0

2

10

65

4

2

16.3

16.2

8.5

1

0

2

Ave.

54

4

1.7

16.99

16.22

9.44

1

0

2

 

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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