Apple Maturity Project has been sponsored by:

Gerber Products Company
Project Greeen
Michigan Apple Research Committee
Michigan Apple Shippers
Michigan State Horticulture Society
Michigan Agriculture Experiment Station
Michigan State University Extension
Valent USA

Honeycrisp – Most blocks have had 2 or 3 pickings thus far. There are still some apples left for the final picking by the end of this week or early next week.

Empire – Five samples were tested last week for the period 9/18-20. Samples came from Oceana County (Elbridge, New Era and Benona area) and from Mason County (Summit). At the time of sampling the blocks were being harvested. There is great variation in size between the samples ranging from 2.5-3” in diameter. Firmness is excellent across the board with the average values from 18.48 to 20.14 lbs. there is very uniform starch conversion regardless of the geographical location and the averages are from 2-3.5 points. Only one sample tested mature on the SI scale. Color was good and in a range from 67.8-91.4%. Brix were very good to excellent with the range for the average values from 12.52-14.9%.

Jonagold – Four samples were tested from Oceana (Elbridge and Benona) and Mason (Riverton and Summit) Counties. All samples tested mature on the starch index scale with the average values in the range from 3.3-5.5. Firmness is excellent with a range from 17.1-20.14 lbs qualifying fruit for long-term CA storage. Excellent brix with the averages in a range from 13.7-16.2%. Harvest is underway.

Jonathan – Four samples were tested from Oceana County (Elbridge, New Era and Benona). There is great variation in size within the samples and between the samples. The average values range from 2.65-2.87” in diameter. Firmness is excellent and very uniform across the samples ranging from 18.23 – 18.43 lbs. All samples tested mature on the starch index scale averaging from 4.5 – 5.4 points. Color is excellent ranging from 93.4-99.6%. Harvest is underway.

Golden delicious – Four samples were tested between 9/18-25. Firmness is excellent and holding. No significant firmness drop in 5 day-period between the two tests. The average values are in the range from 17.94-20.9 lbs. Very nice looking fruit with nice red blush on the sunny side that covers from 27 – 34% of the fruit surface. Background color is still on a green side with the averages ranging from 2.9 – 3.6. Brix are excellent and in a tight range from 14.4-16.6%. Fruit will be entering the optimum window for the long-term CA in about 3-5 days.

Red delicious – Six samples were tested from across the district. Very uniform performance on the starch index scale. All samples are testing immature and in a range from 1.8 to 2.3. Some water core and moldy core are starting to develop. Color is excellent and goes between 95 and 99.4%. Firmness is excellent and in a very tight range between the samples with the values from 17.7-19.3 lbs. Bricks are fare to good and range from 11.1-13.3%. Anticipated harvest in 7-10 days.

Mutsu – One sample from Oceana County (Benona Township) was tested. There is great variation in size from 2.68-3.08” averaging at 2.89” in diameter. Firmness is excellent with the average value of 20.59 lbs. Starch index is indicating the beginning of the starch conversion and is showing solid 2. There is a nice blush on the sunny-side covering 20.5% of the surface. Background color is still more on a green side testing at 3.9. Brix are excellent with the average value of 13.2%. All fruit had blister spot. Anticipated harvest in 7-10 days.

Northern Spy – One sample from New Era was tested. Fruit has great overall size of 3.03” n diameter. There is great variation in firmness within the sample with the values from 13.5 to 23.5 lbs averaging at 20.55 lbs. Similar situation is on the starch index scale where there is a spared from 2-7 averaging at 3.7 placing the fruit on the mature side of t he scale. Brix are excellent averaging at 14.9%. Fruit is ready for harvest.

Low Rome – One sample from Benona Township was tested.Excellent firmness in very tight spread from 22-23.5 lbs. Starch conversion has just started and only the core is cleared. It is testing at solid 2. Fruit is still immature. Excellent color at 98.2%. Brix are good with the average value at 12.8%. In 30% of the fruit there was some color bleed. Anticipated harvest in about 10 days.

Idared – One sample tested from Pere Marquette Township. Overall firmness at 18.46 lbs is excellent, though there is a wide spread in values within the sample going from 15.5-21.5 lbs. Starch index is showing beginning of the conversion into sugar with the values ranging from 1-2 and averaging at 1.8. Fruit is still immature. Brix are very good to excellent averaging at 13%. Anticipation is that the fruit will be within the optimum window for the long-term CA in 10-14 days.

Fuji – One sample from Benona Township was sampled. There is a great variation in size and firmness within the sample. Overall firmness is excellent with the average value of 19.54 lbs. Starch index is 1.9 placing the fruit on the immature side of the scale. There is very little color only 53.5% on the greenish-yellow background. Brix are ranging from 12 to 15 averaging at 13.6. Harvest is expected in 10-14 days.

This report and reports from the other regions of the state will be posted on the web at http://web1.msue.msu.edu/fruit/ripeapple.htm

This information is available on Fruit Code-A-Phone: 1 - 888 - 345 - 0515

Mira Danilovich: Phone: 231-873-2129, e-mail: bulatovi@msu.edu