October 17, 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 #8 – Southeast Michigan

Last Report of the 2007 Apple Harvest Season

APPLE HARVEST SUMMARY

Apple harvest is wrapping up quickly at many fruit farms across the eastern part of the state. Growers have finished up all their major varieties, and most are waiting for the remaining few varieties to mature a bit more before harvest is completed. Most growers across the region have finished up Northern Spy, Idared, Crispin, Law Rome and are working away at Fuji. Most blocks of Braeburn and Granny Smith are unharvested. Many growers have let a good portion of their picking crews go for the season, as there have been many gaps here in maturity toward the end of harvest.

This indeed is the final report of the 2007 apple harvest season. This week’s report is much condensed compared to most, because there are not the number of varieties to sample as last week. I am always interested in feedback on these reports, and the value to you as you have moved through the season. If you have specific comments that you would like to make you can simply click on the following link tritten@msu.edu to send me an email. If you prefer to talk in person, don’t hesitate to either give me a call or visit with me next time we see each other.

I would like to express my thanks to the many growers that participated in the Apple Maturity Project this year. All have helped to make it a meaningful tool for the apple industry. A special word of thanks to the following growers who supplied fruit on a weekly basis over the last eight weeks. This list includes Almar Orchards of Flushing, Erwin Orchards of South Lyon, Hy’s Cider Mill of Romeo, Spicer Orchards of Hartland and Westview Orchards of Romeo. Thanks to my secretary, Debbie Clark for turning around these report so quickly throughout the fall. Also, a special thanks to my wife, Laurie Tritten, for helping to “crunch” all of the data each Tuesday evening over these last eight weeks.

Variety	Color (Range)	Firmness (Range)	Starch (Range)	Brix
Idared	88% (80-95%)	17.3 lbs (14.7-20.0)	7.6 (6.0-8.0)	11.1%
Northern Spy	51% (25-75%)	20.7 lbs (16.3-23.9)	6.3 (3.0-8.0)	12.8%
Braeburn	89% (85-92%)	22.7 lbs (21.8-23.5)	3.5 (3.0-6.0)	12.9%
Granny Smith	21% (5-45%)	18.1 lbs (15.8-20.2)	4.0 (2.0-6.0)	12.8%

INDIVIDUAL VARIETY RESULTS

Idared were sampled for the sixth week of the season, and this week’s small number of samples are from a block that has already been picked once. So it is difficult to compare this week’s maturity to last weeks. Just over 80% of the fruit are showing internal ethylene levels greater than 0.2 parts per million (ppm). The color has continued to improve, now at 88%. The fruit remains fairly firm at 17.3 lbs, however the starch index has now jumped from 3.8 last week to 7.6 this week. The brix has dropped back a bit to 11.1%. With a starch index of 7.6, all this fruit is now mature for immediate fresh market sales, and over mature for medium or long term storage.

Northern Spy were sampled for the fifth week of the season, and again a very limited sample taken because most of the fruit has already been harvested. The fruit that was sampled is a second picking that the grower waited for a bit to get better color on. Virtually 100% of the apples in the sample are showing high internal ethylene levels. The color is about the same at 51%. The pressure is still very firm at 20.7 lbs, however the starch index has jumped from 4.8 last week to 6.3 this week. The brix is 12.8%. All this indicates that this final picking of Northern Spy are indeed ready for harvest at this time. Spy’s picked this late should be marketed immediately and not stored for any length of time. Spy’s are picking very easy and there was an extreme amount of bitter pit on remaining fruit.

Braeburn were sampled for the fourth week of the harvest season. Just over 65% of the fruit are showing internal ethylene levels greater than 0.2 ppm. The color of fruit has improved to 89%, up from 62% last week. The background color continues drop back, and the pressure remains very firm at 22.7 lbs. The starch index has moved from 1.9 last week to 3.5 this week. The harvest window is now open for many blocks of Braeburn across the region. There are some blocks that are a few days away from the beginning of harvest as growers are waiting for fruit to eat a little better and for the starch index to move along a bit further.

Granny Smith were sampled for the third week of the season. The color has improved from 5% last week to 21% this week. The background color remains very green, the fruit remains firm at 18.1 lbs. The starch removal has jumped from 2.6 last week to 4.0 this week, with a brix of 12.8%. Granny Smith are not ready for harvest at this time, they should be ready in a week or so. Granny Smith are eating much better than they typically do as a result of this long growing season.

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). This same harvest information is also available on the SE Michigan Fruit Pest Management Code-A-Phone (810-732-1005). For reports from other regions, click on the following link http://web1.msue.msu.edu/fruit/ripeapple.htm .

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.