September 5, 2007

 

TO:                  Apple Growers in Southeast Michigan 

                        MSU Extension Fruit Educators and Specialists

 

FROM:             Bob Tritten

                        District Extension Fruit Educator

 

SUBJECT:        Apple Harvest Update Report #2 – Southeast Michigan 

 

APPLE HARVEST SUMMARY

 

Growers are on the downhill side of finishing off Gala harvest across the region, and are working away at McIntosh harvest.  Gala’s are around 60% to 80% harvested, with Mac’s being about 40% harvested.  Many McIntosh blocks and strains are on the green side at this time and need more time to mature.  Honeycrisp have been harvested once at many farms, and are ready for a light second picking at this time.  Empire, Cortland, Jonagold and Jonathan were sampled for the first time this season to get an early read at their maturity.  I will include details on these varieties in the report, but none are ready for harvest at this time.

 

Variety

Color (Range)

Firmness (Range)

Starch (Range)

Brix

McIntosh

65% (49-79%)

16.9 lbs (14.6-18.7)

3.9 (2.9-5.2)

12.3%

Gala

80% (55-94%)

20.7 lbs (17.5-23.6)

3.8 (1.5-6.8)

13.3%

Honeycrisp

45% (14-65%)

17.4 lbs (15.4-18.7)

3.2 (1.6-4.0)

14.1%

Empire

52% (39-64%)

18.6 lbs (17.9-19.2)

2.4 (2.0-2.8)

11.0%

Cortland (Redcort)

62% (40-75%)

17.3 lbs (16.1-18.8)

1.2 (1.0-1.6)

12.6%

Jonagold

41% (7-74%)

19.0 lbs (17.8-20.2)

2.0 (1.8-2.2)

12.8%

Jonathan

40% (25-50%)

18.8 lbs (15.8-22.0)

2.0 (2.0-2.0)

12.1%

 

INDIVIDUAL VARIETY RESULTS

 

McIntosh were sampled for the second week this season, with a good number of samples from across the region.  In some cases the strains sampled needed to be changed because some that were sampled last week had been harvested in the meantime.  For the second year in a row, we are picking Gala ahead of McIntosh this year.  Ethylene levels in McIntosh were showing at 24% of fruit were about .02 parts per million (ppm).  While this is lower than last week, remember that I needed to switch many strains.  Color in McIntosh is 65%, about the same as last week, with a range of 49% to 79%.  The pressure has dropped from 17.5 lbs last week to 16.9 lbs this week.  Starch has risen from 3.4 last week to 3.9 this week, which would be a typical rise during hot weather conditions.  Brix has remained nearly the same at 12.3.  McIntosh drop is continuing in many blocks across the region, however not all of them.  It appears that most of this drop is caused by fruit pushing off the limb as McIntosh has their typical short stem.  However Mac’s picked very easy for the second week in a row this season, and I am always concerned about the possibility of heavy wind coming along and causing drop.  When I look over the tops of bins of harvested McIntosh, I see that most farms have poor color this year.  The best advice I can give at this time is for growers to go slow on McIntosh harvest this year, hoping for better color, flavor and definitely better size.  There is a risk in this strategy however in that if we have a wind storm; there may be some fruit loss on the ground.

 

Gala were sampled for the second time of the season, with a good number of block’s samples.  Color has remained the same as last week, at about 80%.  The pressure has dropped from 23.0 lbs last week to 20.7 lbs this week.  The starch index has risen from 1.6 last week to 3.8 this week.  The brix has jumped from 12.7 last week to 13.3 this week.  Close to 86% of the Gala’s showed internal ethylene levels greater than 0.2 ppm.  Many strains of Gala appear to be mature or over mature at this time for the long-term and controlled atmosphere storage.  So my suggestion is that growers concentrate their effort on picking Gala’s at this point in time to maintain as much fruit quality as possible.  This will most likely be the last week of the season for sampling Gala.  Overall size was a problem this year in Gala.  Lastly, I saw my first bit of stem end cracking in Gala that was harvested on Monday.  This is another one of Gala’s problems that appears to be accentuated in warmer seasons.

 

Honeycrisp were sampled for the second time this year, with a much broader sample than last week.  Just over 77% of fruit showed 0.2 ppm of internal ethylene.  Color is all over the board this year in many blocks of Honeycrisp, ranging from 14% to 65%, with an average of 45%.  Firmness remains good at 17.4 lbs, although that is quite a drop from last week’s limited sample of 20.1 lbs.  Starch index moved from 2.2 last week to 3.2 this week.  The brix has jumped from 12.2 last week to 14.1 this week.  Most growers have done a light first picking of Honeycrisp over the last week, and I would say based on the results of this extensive sampling, that most blocks are ready for a second light picking.  However I think that many Honeycrisp fruit need more time to color and gain better flavor.  So, this season I think that the third picking of Honeycrisp will be our heavy picking, with the fourth a clean up picking.

 

Empire were sampled for the first time this year, with 52% color, and 18.6 lbs pressure.  The starch index is 2.4, which is much higher than I thought it would be.  The brix is 11.0 and background color of 3, out of a scale of 1 – 5.  So Empire are not ready for harvest at this time, however a week to 10 days from now I will most likely be advising harvest of Empire for controlled atmosphere and long-term storage, and possibly some fresh market harvest on early maturing sites.

 

Cortland were sampled for the first this year, with all of the samples being the Redcort strain.  Color is ok at 62%, with firmness at 17.3 lbs.  The starch index is 1.2, and brix 12.6.  Again this variety is not ready for harvest at this time.

 

Jonagold were sampled for the first time of the year, with 41% color, however range was wide from 7% to 74%.  The fruit is firm at 19.0 lbs, and the starch index is 2.0.  The brix is currently 12.8.  Based on these samples it appears at this time that Jonagold are ahead of Cortland this year.

 

Jonathan were sampled for the first time this week, and a very small sample at that.  Color has a long ways to go yet on Jonathan, with 40% color at this time.  Fruit is fairly firm at 18.8 lbs and the starch index is 2.0.  The brix reported at 12.1.  Obviously, Jonathan are not ready for harvest at this time, however they may be ready in 10 to 14 days. 

 

Table 1. 2007 predicted peak harvest dates.

Full bloom date

Predicted harvest date

 

Station

McIntosh

Jons

Reds

McIntosh

Jons

Reds

Observer

SWMREC

4-30

5-2

5-2

8-27

9-15

9-21

Shane

Deerfield

5-5

5-6

5-8

9-1

9-15

9-22

Tritten

Flint

5-5

5-5

5-7

9-3

9-12

9-19

Tritten

Peach Ridge

5-5

5-7

5-8

9-1

9-19

9-26

Schwallier

Ludington

5-9

5-11

5-10

9-14

9-21

9-27

Danilovich

NWMHRS

5-11

5-11

5-11

9-9

9-18

9-24

Rothwell

If you have any questions regarding this Apple Maturity Harvest Update, don’t hesitate to email me (tritten@msu.edu) or call (810-732-2177).  If you would like this information sent to you via email instead of fax, please let me know and that can be accomplished very quickly.  This same harvest information is also available on the SE Michigan Fruit Pest Management Code-A-Phone (810-732-1005).

 

Project Researchers – Dr. Randy Beaudry MSU Horticulture Department,  and Bob Tritten

This report and project is made possible by the support of our sponsors which include Gerber Products Company, Michigan Apple Shippers Association,Valent USA, MSU Project GREEEN, Michigan Apple Research Committee, Michigan State Horticultural Society, Michigan Agricultural Experiment Station, and Michigan State University Extension.  The growers cooperating by supplying apples on a weekly basis in Southeast Michigan include AlMar Orchards in Flushing, Erwin Orchards in South Lyon, Spicer Orchards in Hartland, Westview Orchards in Romeo, and several others.