October 3, 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 #6 – Southeast Michigan 

 

APPLE HARVEST SUMMARY

 

The best way I can describe apple harvest at this time is that growers are moving ahead, however at a much slower pace than their normal harvest.  On Monday, I heard a couple growers describe that they have “throttled back” their harvest to accommodate the slow ripening of many varieties, and lack of a crop.  Our crop continues to pick out light.  Red Delicious appears to be one exception to that general rule across the region this year.  Harvest labor is plentiful this year.  Most growers have not had any difficulty with adverse weather conditions slowing harvest this year.  In fact many growers gave harvest crews some time off over the last week to accommodate slow ripening and to make adjustments for the short crop.

 

Growers are finishing up Empire, Jonagold and Golden Delicious, and are harvesting Idared, Red Delicious, and Northern Spy.  Fuji and Law Rome are ready or nearly ready to begin harvest any time.  Crispin, Braeburn, Winesap, and Granny Smith are not ready to harvest at this time.

Variety

Color (Range)

Firmness (Range)

Starch (Range)

Brix

Empire

77% (58-90%)

17.0 lbs (12.3-20.4)

5.5 (4.0-6.0)

12.8%

Jonagold

71% (54-88%)

17.6 lbs (17.2-18.0)

6.5 (5.5-7.5)

15.3%

Golden Delicious

14% (8-21%)

16.7 lbs (15.9-17.3)

5.8 (5.1-6.9)

15.7%

Crispin

10% (0-30%)

19.4 lbs (18.4-20.9)

2.2 (1.6-2.7)

13.3%

Red Delicious

87% (80-93%)

16.4 lbs (15.3-17.3)

3.3 (2.4-4.1)

13.1%

Idared

76% (69-82%)

16.2 lbs (14.6-17.6)

3.3 (1.8-5.6)

12.2%

Northern Spy

35% (15-83%)

19.6 lbs (18.8-21.4)

3.1 (2.7-3.3)

12.4%

Winesap

87% (80-95%)

18.5 lbs (15.8-21.7)

1.4 (1.0-2.0)

12.6%

Fuji

68% (62-74%)

18.1 lbs (17.8-18.6)

4.4 (4.0-4.9)

13.3%

Law Rome

94% (87-100%)

20.8 lbs (20.3-21.3)

3.6 (3.0-4.7)

12.9%

Braeburn

65% (58-71%)

22.4 lbs (22.0-22.8)

1.9 (1.5-2.2)

12.9%

Granny Smith

8% (0-20%)

18.6 lbs (16.6-21.4)

2.0 (2.0-2.0)

11.2%

 

INDIVIDUAL VARIETY RESULTS

 

Empire were sampled for the fifth week of the season, and I just looked at one sample for the week.  Most Empires have now been harvested.  Virtually all (100%) the fruit is now showing internal ethylene levels greater than 0.2 parts per million (ppm).  The fruit color remains the same at 77%.  The background color has dropped from 2.1 last week to 1.4, with pressure at 17.0 lbs.  The starch removal has moved from 3.6 last week to 5.5 this week.  The brix is 12.8%.  All of these are indications that indeed this variety has been ready for harvest at many farms, and is now ready for harvest at this one particular farm that the sample was taken.

 

Jonagold were harvested for the fifth week of the season.  The Jonagold harvest window has been longer than what I have seen in the past.  In some cases the strains that were sampled this week were the older strains, which tend to mature later in the season and have a bit poor color.  65% of the fruit were showing internal ethylene levels greater than 0.2 ppm.  The color remains about the same at 71%, and pressure is up from 16.5 lbs last week to 17.6 lbs this week.  The starch index has jumped from 5.5 last week to the 6.5 this week.  The brix has jumped to 15.3%.  All these are indications that Jonagold are indeed are ready for harvest at this time.  This will be the last week for sampling Jonagold, as I am certain that it will be harvested by the end of the week.

 

Golden Delicious were sampled for the fourth week of the season, with another extensive sample taken this week.  Many blocks of Golden’s have been harvested or else picked at least once over the last week, so some of my samples are from later maturing blocks or strains or are second picking.  48% of the sample showed internal ethylene levels greater than 0.2 ppm.  The color is about the same at 14%.  The background color has improved dramatically, and the pressure has dropped from 19.6 lbs last week to 16.7 lbs this week.  Starch removal has also jumped from 3.3 last week to 5.8 this week.  The brix has also jumped a point and a half to 15.7%.  All of these are indications that Golden Delicious indeed are ready for harvest at this time.  This may be the last week sampling Golden’s.

 

Crispin were sampled for the fourth week of the season.  The internal ethylene levels are actually down a bit this week as compared to last week, and is currently at 23% fruit showing greater than 0.2 ppm.  The color has improved a bit from 7% last week to 10% this week.  The background color has dropped almost a point, and the firmness has increased from 18.9 lbs last week to 19.4 lbs this week.  Starch removal seems to be the same at 2.2, with a brix of 15.3%.  Crispin are not ready for harvest at this time, and this variety has matured very slowly this season.  I would say that all blocks require another week before Crispin will indeed be ready for harvest.

 

Red Delicious were sampled extensively across the region over the last week.  Many growers have started picking earlier maturing strains of Red Delicious.  Most of my samples were Red Chief strains, where available.  93% of the Red Delicious are showing internal ethylene levels greater than 0.2 ppm, indicating that fruit is maturing fairly quickly.  Color remains good  at 87%, and the background color has dropped a bit.  The pressure has also dropped on Red Delicious from 17.1 lbs last week to 16.4 lbs this week.  The starch index has moved from 2.8 last week to 3.3 this week.  With a brix currently at 13.1%.  Red Delicious indeed are ready for harvest at some farms, and need another few days to almost a week at other farms.  Red Delicious are not maturing consistently across the region this year.  Red Delicious fruit continue to pick very easily this week, and fruit drop was greater than last week.

 

Idared were sampled more extensively this week than last week, and for the third week of the season.  Internal ethylene levels are about the same at 54% of fruit showing greater than 0.2 ppm.  Color has moved from 67% last week to 76% this week.  The pressure remains about the same at 16.2 lbs, which I think is on the low side for Idared’s.  The starch removal however jumped from 1.9 last week to 3.3 this week, with a brix of 12.7.  Many blocks of Idared are ready for harvest at this time, and there is quite a spread of maturity this week from fruit that is definitely not ripe, to fruit that is a bit on the over mature side.

 

Northern Spy were sampled for the third week of the season, with a more extensive sample than last week.  90% of the fruit are showing internal ethylene levels greater than 0.2 ppm.  The color has improved from 29% last week to 35% this week.  The background color has also improved greatly over last week.  The pressure remains unchanged at 19.6 lbs.  Starch removal also remains unchanged at 3.1, however the spread of maturity is much tighter this week than what it was last week.  The brix is 12.4%.  Some blocks of Northern Spy are indeed ready for harvest at this time, while others remain on the green side and require another 4 or 5 days before being mature.

 

Winesap were sampled for the first week of the season, so this is just a preliminary look at the variety.  Only 10% of the fruit is showing internal ethylene levels greater than 0.2 ppm.  The color is good at 87% and the background color is mediocre at 3.0.  The fruit remains firm at 18.5 lbs.  The starch removal is 1.4, with a brix of 12.6%.  Winesap are not ready for harvest at this time, look for more details next week.

 

Fuji were sampled for the third week of the season, again with a more extensive sample than last week.  A bit more of the fruit is showing internal ethylene levels greater than 0.2 ppm than last week.  The fruit color has moved from 48% last week to 68% this week.  The pressure remains unchanged at 18.1 lbs, however the starch index has moved from 2.3 last week to 4.4 this week.  The brix remains unchanged at the 12.3%.  Some blocks of Fuji are indicating that they are ready for harvest at this time, while others are not quite there yet, and will require another 4 or 5 days for them mature.  Fuji is another example of a variety that has jumped ahead of several others this year, and indeed is ready for harvest or nearly ready for harvest at most farms.

 

Law Rome were sampled for the second week of the season, with another sample added to the mix this week.  45% of the fruit are showing internal ethylene levels greater than 0.2 ppm up from 10% last week.  The color remains excellent at 94%.  The background color has improved a bit on Rome’s as well to 2.1.  The pressure remains very firm at 20.8 lbs, down from 21.5 lbs last week.  The starch removal has moved from 3.1 last week to 3.6 this week.  The brix is at 12.9%.  While Law Rome’s are not ready for harvest at this time, they are closer than what I had certainly thought they were at this time last week.  In fact, there are indications that there are some blocks that are just a few days away from being ready for harvest at this time.

 

Braeburn were sampled for the second week of the harvest season, with a few more samples being taken than last week.  50% of the fruit is showing internal ethylene levels greater than 0.2 ppm, up from 20% last week.  The color remains fairly good at 65%.  The pressure remains very firm at 22.4 lbs.  Starch index has moved from 1.0 last week to 1.9 this week, with a brix of 12.9%.  While Braeburn are not ready for harvest at this time, I would say that by next week at this time we will have a clearer picture of when they will be ripe, but most likely it is at least 10 days to 2 weeks off.

 

Granny Smith were sampled for the first time of the season, and mainly to get an early read on maturity of this variety.  None of the fruit is showing internal ethylene levels greater than 0.2 ppm.  The color is 8%.  The background color is 5.0, a good indication that they are very green at this time.  The pressure is firm at 18.6 lbs.  Starch index is currently 2.0, with a brix of 11.2%.  Granny Smith are not ready for harvest at this time, however with the long warm and sunny growing season that we experienced this year, if there is any year that Granny Smith might be close to being mature, it should be this year.  I expect that we are still about 3 weeks off from Granny Smith harvest at this time, look for a more details next week.

 

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, Hy’s Cider Mill in Romeo,  Spicer Orchards in Hartland, Westview Orchards in Romeo, and several others.