Southeast Michigan apple maturity report - September 21, 2016

Jonagold and Jonathan harvest is underway. Honeycrisp growers are waiting for more fruit to mature to do their third or fourth picking.

General apple harvest comments

Many blocks of Jonagold and Jonathan are ready for harvest, and growers are waiting for the next picking of Honeycrisp to mature. Retain treated Gala and McIntosh blocks are also being harvested. Some growers are finding a gap in apple maturity. Empire is slow to mature this season, and is not ready.

This is the third apple harvest report for the season; I have collected and analyzed apples for the last four weeks. This week, eight apple varieties were sampled and tested for maturity, with Red Delicious, Northern Spy and Crispin being added to the mix.

Brix levels took a nice jump this past week. Cider makers are able to find a better mix of apples for cider; it tastes better this week due to this. Fruit size is generally fair to good this season, but due to the drought, not as large as most years. For the most part, varieties are picking out as growers had expected; we have a good apple crop, but not as large as the Ridge. Harvest labor is generally in short supply.

As a reminder, with the early and long bloom in apples this spring and the continued heat of this summer, apple growers are finding that apple maturity is much less uniformity than in most years. This mixed maturity was the case for McIntosh, Gala and Honeycrisp. The harvest window for early maturing apple varieties (Gala, McIntosh, Honeycrisp and Early Fuji) was a few days ahead of the predicted harvest dates. However, based on data from this week, Empire will be maturing at least two weeks behind the predicted harvest date of Sept. 14.

The normal and 2016 peak harvest dates for apple varieties in east Michigan table continues to be included at the end of this report. I encourage apple growers to spend some time in the orchard to evaluate the maturity of your apple varieties to make sure you are on top of apple harvest.

Black rot on fruit remains a problem at several farms, much worse in many blocks than the last few seasons. Sooty blotch and flyspeck are showing up more and more this week. Growers are encouraged to be on the lookout for brown marmorated stink bugs as fruit is being harvested.

Apple maturity in east Michigan for apples harvested Sept. 19

Variety

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Empire

30 (0-100)

79 (71-85)

17.8 (16.8-19.1)

2.5 (1.8-3.4)

11.6

Jonathan

20 (10-40)

90 (85-94)

17.5 (16.3-19.5)

3.0 (1.8-4.9)

13.7

Jonagold

13 (0-40)

56 (38-85)

17.0 (16.1-18.9)

5.1 (2.9-6.3)

13.0

 

Cortland

15 (10-20)

75 (70-80)

16.4 (16.3-16.4)

1.1 (1.0-1.2)

11.7

Golden Delicious

0 (0-0)

16 (2-36)

18.3 (16.1-19.4)

2.2 (1.0-4.8)

12.7

Red Delicious

7 (0-10)

89 (85-95)

17.3 (16.7-17.6)

1.8 (1.7-1.9)

10.4

Northern Spy

30 (30-30)

13 (5-30)

21.1 (16.0-26.0)

1.2 (1.0-3.0)

11.2

Crispin

0 (0-0)

12 (5-20)

19.0 (17.0-22.0)

1.2 (1.0-2.0)

11.8

Individual variety results

Empire was sampled for the third week of apple harvest. Empire is maturing very slowly this season, slower than any other apple variety tested so far this season. The predicted harvest date for Empire was Sept. 14. In last week's report I said Empire was at least a week away from being ready to harvest, but this week I am saying the same thing: at least a week away from being ready to harvest.

The percentage of fruit with internal ethylene levels greater than 0.2 parts per million (ppm) has risen from 3 percent last week to 30 percent this week. Fruit color has improved to 79 percent, with fruit pressure still firm but dropping to 17.8 pounds. The starch index moved from 1.8 last week to 2.5 this week. They are eating a little better than last week, but are still eating green.

Empire 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 5

7 (0-20)

53 (39-62)

21.0 (19.8-22.7)

1.8 (1.6-2.0)

10

Sept. 12

3 (0-10)

76 (62-86)

19.4 (19.1-19.5)

1.8 (1.0-2.4)

10.9

Sept. 19

30 (0-100)

79 (71-85)

17.8 (16.8-19.1)

2.5 (1.8-3.4)

11.6

Jonathan was sampled for the second week of the season. The predicted harvest date for Jonathon is Sept. 24. Some blocks and strains of Jonathan are ready now for harvest, while others need another five days or so to mature well. Now is time to sample each of your Jonathan blocks for maturity. Overall, Jonathan maturity is ahead of Empire this season; most Jonagold blocks are ahead of Jonathan this season.

The percentage of fruit with internal ethylene levels greater than 0.2 ppm dropped for some reason, from 43 percent last week to 20 percent this week. Fruit color remains excellent at 90 percent and the fruit remain firm with a pressure of 17.5 pounds, dropping from 18.6 pounds last week. The average starch index has gone down from 3.7 last week to 3.0 this week. One of the three blocks tested this week are significantly ahead of the others with a starch index of 4.9. The brix has greatly improved this week from 11.9 last week to 13.7 this week.

Jonathan 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 12

43 (0-80)

90 (78-98)

18.6 (17.6-19.2)

3.7 (1.3-4.9)

11.9

Sept. 19

20 (10-40)

90 (85-94)

17.5 (16.3-19.5)

3.0 (1.8-4.9)

13.7

Jonagold was sampled for the second week of apple harvest. The predicted harvest date for Jonagold is Sept. 24. Three of the four Jonagold blocks tested this week are mature and need to be harvested ahead of Jonathan. Again, Jonagold appear to be ahead of Empire.

The percentage of fruit with internal ethylene levels greater than 0.2 ppm is 13 percent, with fruit color jumping from 23 percent last week to 56 percent this week. Pressure is firm at 17.0 pounds and starch index is averaging 5.1. With the exception of just one block tested, all others tested to mature to over mature.

Jonagold 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 12

0 (0-0)

23 (16-29)

17.5 (16.7-18.3)

3.9 (1.6-6.1)

11.6

Sept. 19

13 (0-40)

56 (38-85)

17.0 (16.1-18.9)

5.1 (2.9-6.3)

13.0

Cortland was sampled for the second week of the season, with a predicted harvest date of Sept. 24. At this time they appear to be behind Empire. The percentage of fruit with internal ethylene levels greater than 0.2 ppm is 15 percent, with fruit color good at 75 percent. Pressure is firm but dropping to 16.4 pounds, and starch index at 1.1.

Last week there was a wide or broad spread of maturity in the two blocks tested. This week there is more uniformity in the data. One of the samples tested last week was a really early maturing strain of Cortland.

Cortland 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 12

5 (0-10)

68 (50-86)

17.3 (17.0-17.6)

3.8 (1.2-6.3)

 

12.1

Sept. 19

15 (10-20)

75 (70-80)

16.4 (16.3-16.4)

1.1 (1.0-1.2)

11.7

Golden Delicious was sampled for the second week of apple harvest, with a predicted harvest date of Sept. 30, or 11 days from the date this week’s sample was taken. The sample size was expanded this week compared to last week. They are immature and still eating green.

The percentage of fruit with internal ethylene levels greater than 0.2 ppm remains at 0 percent or none, with fruit color improving to 16 percent. Pressure is firm at 18.1 pounds and starch index dropped from 2.8 last week to 2.2 this week.

Golden Delicious 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 12

0 (0-0)

5 (0-10)

18.1 916.4-19.7)

2.8 (1.8-3.8)

11.5

Sept. 19

0 (0-0)

16 (2-36)

18.3 (16.1-19.4)

2.2 (1.0-4.8)

12.7

Red Delicious was sampled for the first week of the season, mainly to get an early read on its maturity. All samples tested are Redchief. The predicted harvest date for Red Delicious is Oct. 1, or 12 days from the date of this sampling. Red Delicious is still very green and is not ready for harvest.

The percentage of fruit with internal ethylene levels greater than 0.2 ppm is 7 percent, with fruit color good at 89 percent. Pressure is firm at 17.3 pounds and starch index is at 1.8.

Red Delicious 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 19

7 (0-10)

89 (85-95)

17.3 (16.7-17.6)

1.8 (1.7-1.9)

10.4

Northern Spy was sampled for the first week of apple harvest, mainly to get an early read on its maturity. They are still immature and are eating very green. The percentage of fruit with internal ethylene levels greater than 0.2 ppm is 30 percent, with fruit color poor at 13 percent. Pressure is firm at 21.1 pounds and starch index is at 1.2.

Northern Spy 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 19

30 (30-30)

13 (5-30)

21.1 (16.0-26.0)

1.2 (1.0-3.0)

11.2

Crispin or Mutsu was sampled for the first week of the season, mainly to get an early read on its maturity. Crispin is still very immature and not ready for harvest. The percentage of fruit with internal ethylene levels greater than 0.2 ppm is 0 percent or none, with fruit color at 12 percent. Pressure is firm at 19.0 pounds and starch index is at 1.2.

Crispin 2016 maturity sampling for the harvest season

Date of sample

% Fruits with ethylene over 0.2 ppm (range)

Color % (range)

Firmness Lbs. (range)

Starch (range)

Brix %

Sept. 19

0 (0-0)

12 (5-20)

19.0 (17.0-22.0)

1.2 (1.0-2.0)

11.8

Predicted apple harvest dates

Each year we publish predicted harvest dates for three varieties for many locations across the state. This year's “Predicted 2016 apple harvest dates” were published July 11. The table below has been expanded to include more apple varieties and it lists only one date for the entire region, which is hard to do. The information in the “Predicted 2016 apple harvest dates” article lists the bloom and harvest dates for Deerfield and Romeo, Michigan. You can adjust your predicted harvest dates based on your bloom dates or make adjustments to this expanded list based on the typical harvest dates at your farm. These predicted harvest dates are based on a long-established formula using the bloom date and temperatures for 30 days post-bloom.

These dates are an estimate. I believe our actual harvest dates may be a few days ahead of these predicted harvest dates for most varieties. Keep a close eye on the weekly apple harvest updates for possible revisions of these dates.

Normal and 2016 peak harvest dates for apple varieties in east Michigan

Variety

Normal date

2016 predicted date

Paula Red

8/22/16

8/17/16

Gingergold

8/23/16

8/18/16

Gala

9/8/16

9/5/16

McIntosh

9/13/16

9/7/16

Early Fuji

9/14/16

9/10/16

Honeycrisp

9/16/16

9/11/16

Empire

9/20/16

9/14/16

Jonathan

9/23/16

9/24/16

Jonagold

9/23/16

9/24/16

Cortland

9/25/16

9/24/16

Golden Delicious

9/29/16

9/30/16

Red Delicious

10/1/16

10/1/16

Ida Red

10/6/16

10/6/16

Rome

10/11/16

10/11/16

Fuji

10/22/16

10/22/16

Braeburn

10/23/16

10/23/16

Goldrush

10/31/16

10/31/16

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

The East Michigan Apple Harvest Report is produced by Bob Tritten, district fruit educator in Flint, Michigan. Email: tritten@msu.edu; Office phone: 810-244-8555; Cell: 810-516-3800; and Fax: 810-341- 1729. Special thanks to the four orchards that allow me to harvest fruit for analysis every Monday during the apple harvest season: Spicer Orchards in Hartland, Erwin Orchards in South Lyon, Westview Orchards in Romeo and Hy's Cider Mill in Romeo. Thanks to so many other orchardists that I collect fruit samples from to include their varieties on more of a random basis. Lastly, thanks to the Post-Harvest Lab in the Department of Horticulture at Michigan State University that provides the quick and very accurate analysis of so many apple samples in the fall. Randy Beaudry and his students do a fantastic job and are a valuable part of our Apple Maturity Team.

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