TO: Apple Growers in Southeast Michigan
MSU Extension Fruit Educators and Specialists
FROM: Bob Tritten
District Extension Fruit Educator
SUBJECT: Apple Harvest Update Report #3 –
APPLE HARVEST SUMMARY
Growers are nearing an end of
McIntosh harvest, and Gala harvest finished for the most part last week. Honeycrisp are being picked for the fourth
and in most cases the final time. There
appears to be a gap in apple maturity this year between the varieties that I’ve
just listed and the next group that are coming along, which include Empire,
Cortland, Jonagold and Jonathan. So, to
keep harvest crews around, growers have been looking for other jobs for them
over the last several days. I sampled
Golden Delicious, Red Delicious and Crispin for the first time this season, it
appears at this early stage that Golden’s will be behind Red Delicious this
year, but more details will follow from results from next week’s apple maturity
sampling. The order of apple maturity is
definitely different this year than any other year that I have seen. While we have had seasons where Gala were
harvested ahead of Mac’s, other varieties like Jonathan and Red Delicious
appear to be maturing quickly, and Empire, Cortland and Golden Delicious are
maturing very slowly. There is also
quite a spread in maturity on the tree this year, due to the fact that so much
of our fruit this season is born on one year old wood. Fruit born on one year old wood generally
matures more slowly than fruit on wood that is two or more years older. Thus, there will be quite a spread of
maturity on one tree this year for most varieties.
Variety |
Color
(Range) |
Firmness
(Range) |
Starch
(Range) |
Brix |
|
McIntosh |
62% (58-66%) |
15.6 lbs
(15.1-16.7) |
5.3 (5.0-5.5) |
12.1% |
|
Honeycrisp |
76% (61-87%) |
14.9 lbs
(13.4-17.8) |
5.9 (4.7-7.0) |
14.1% |
|
Empire |
70% (56-77%) |
17.1 lbs
(16.0-17.6) |
2.5 (1.5-3.7) |
11.9% |
|
|
67% (39-87%) |
16.1 lbs
(14.4-18.1) |
1.2 (1.0-1.5) |
13.0% |
|
Jonagold |
41% (9-72%) |
22.3 lbs
(16.8-21.0) |
2.3 (2.0-2.6) |
13.3% |
|
Jonathan |
60% (51-78%) |
15.6 lbs
(15.3-15.9) |
4.1 (3.8-4.4) |
13.2% |
|
Golden Delicious |
4% (0-9%) |
18.0 lbs
(16.5-19.1) |
1.3 (1.0-1.6) |
13.9% |
|
Crispin |
5% (4-7%) |
22.0 lbs
(20.5-22.6) |
1.5 (1.0-2.0) |
12.1% |
|
Red Delicious |
75% (64-90%) |
16.5 lbs
(16.0-17.0) |
2.0 (1.6-2.3) |
11.5% |
INDIVIDUAL VARIETY RESULTS
McIntosh
were sampled for the third time of the season.
It was difficult to sample the same exact strains of McIntosh that I did
last week, as most of those were already harvested. The sample results from this week are for
later maturing strains, so the data is going to be hard to compare to last
week. A good amount of this late McIntosh
is showing internal ethylene levels greater than 0.2 parts per million (ppm). The color is fairly good at 62%, and
background color is now indicating that fruit is mature. The fruit firmness has dropped to 15.6 lbs,
from 16.9 lbs last week. The starch
index for this week’s fruit averaged 5.3, with a brix of 12.1%. All this indicates that the remaining
McIntosh are indeed ready for harvest.
This will be the last week for sampling McIntosh.
Honeycrisp
were sampled this week as well. It is
difficult to compare to last week’s results as growers are picking Honeycrisp
three and four times to insure maximum fruit quality. All (100%) of the fruit sampled this week were
showing greater than 0.2 ppm of internal ethylene. The pressure has dropped from 17.4 lbs last
week to 14.9 lbs this week. The starch
index has moved along quickly from 3.2 last week to 5.9 this week. The brix remains about the same at 14.1%. All these indices are pointing to the fact
that Honeycrisp is now ready for its fourth and possibly final picking.
Empire were
sampled for the second week of the season, with an increase in the number of
samples taken. Empire are showing low
levels of internal ethylene and fairly good color at 70%, up from 52% last
week. The pressure has dropped from 18.6
lbs last week to 17.1 lbs this week. The
starch index has remained nearly the same at 2.5. Brix has moved a bit from 11.0% last week to
11.9 this week. With starch index at
2.5, this indicates that Empire are not ready for harvest at this time. I think that they need to have another week
or so before the starch index levels begin to come up.
Jonagold
were sampled for the second time of the season.
Color is virtually unchanged, however the starch index has moved from
2.0 last week to 2.3 this week. The
fruit is still very firm at 22.3 lbs.
Jonagold are not ready for harvest at this time, they are moving along
on a rather slow pace this year and will most likely be harvested well after
Jonathan and just before Golden Delicious.
As I indicated in last week’s report, it also appears that Jonagold are
ahead of
Jonathan
were sampled for the second time this season, with a larger sample than last
week. They are showing high levels of
internal ethylene, with fairly good color at 60%, up from 40% last week. Pressure has dropped from 18.8 lbs last week
to 15.6 lbs this week. The starch has
also moved along fairly quickly from 2.0 last week to 4.1 this week. The brix has also jumped to 15.2% this
week. Based on all these indices, it
appears that Jonathan are ready for harvest for the long-term and CA storage at
this time, and ready for fresh fall sales later this week.
Golden Delicious were sampled for the first time this year, with a good number of
samples taken. They are showing low
levels of internal ethylene, with poor color at this time. The background color is also poor. The fruit is firm at 18.0 lbs, with a starch
index of 1.3. The brix is very good at
13.9%. This sample was taken to be an “early
look” at Golden Delicious. It appears
that it is maturing very slowly this year.
Crispin were
sampled for the first time for the season as well. There is no internal ethylene, poor color and
background color, and the fruit is staying firm at this time at 22.0 lbs. The starch index is 1.5, all indicating that
fruit is not mature at this time.
Red Delicious
were sampled rather extensively for the first time this season. A full 33% of the fruit is showing internal
ethylene levels greater than 0.2 pmm.
Color is good at 75% and background color is already down to 2.5 (on a
scale of 1 to 5 with 5 being green and 1 being mature). Fruit firmness was surprisingly low at 16.5
lbs, with a range of 16.0 to 17.0. The
starch index was a 2.0, with brix at 11.5%.
However it is too early to begin harvest of Red Delicious, based on this
one week’s worth of data. It appears
that Red Delicious are ahead of Golden’s this year, and that they are maturing
fairly quickly. Where possible I sampled
Red Chief strains of Red Delicious.
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 |
|
|
5-5 |
5-6 |
5-8 |
9-1 |
9-15 |
9-22 |
Tritten |
|
|
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