In This Issue:
Calendar
Effect of Rain on Fungicide Wash-Off
OFGS Summer Tour a Sucess
Mite Control Update
A Banner Year for Apple Summer Diseases
Sovran & Flint for Control of Sooty Blotch & Flyspeck
Apple Crop Load Management
Checking for Oriental Fruit Moth Damage in Apples and Peaches
Degree Day Accumulations
Pest Phenology
Fruit Observations & Trap Reports
August 4-5: HACCP Workshop, Leesport, PA. A
Hazard Analysis Critical Control Point (HACCP)
workshop will take place at the Berks County Ag Center
in Leesport, PA. For more information please contact
Dr. Luke LaBorde, Penn State University, at 814-863-2298 or e-mail at I've had several calls this year (and in years
past) from growers wanting to know what they should
do about spraying their grapes with all the rain we've
had lately. They can't spray "because it's always
raining" is the common complaint. That reminded me
that we ran a article about this time last year written by
Jim Travis, Plant Pathologist at Penn State. Jim noted
that if you are using protectant fungicides, you need to
consider the effect of rain on wash-off of the materials.
The strobilurin (Abound, Sovran, Flint) and
sterol inhibitor (Nova, Procure, Rubigan) fungicides are
absorbed into the leaf and fruit tissue after application
(once the residue has dried) and are not affected by rain
wash-off. The protectant (Dithane, Manzate,
Penncozeb, Captan, Ziram, Thiram, Polyram) fungicide
residues can be affected by rain. A general rule-of-thumb for the effect of rain on washing-off protectant
fungicides follows:
So, during all this rainy weather, growers have
a couple of options. They can use the new strobilurins
or sterol inhibitors and time sprays so that residues dry
on the plants before the next rain event, or they can
continue to use protectants and monitor rainfall to
determine appropriate timing of the next spray. NOT
spraying because of frequent rainfall is not an option
unless you want to have a major disease outbreak. We
are still in the critical period for control of black rot.
The first two post-bloom sprays are critical. So don't
let a little rain stop you from getting your job done!
Fruit growers' expectations were as high as the
temperature for the 2003 Ohio Fruit Growers Society
Summer Tour at Glen Hill Orchards in Mount Vernon,
Ohio. The June 25th tour was a resounding success, as
over 300 enthusiasts toured the immaculate farmstead
and orchard. Hosts Maureen Buchwald and Rich
Ridenbaugh showcased their 106 acres of apples and
peaches, while over 30 exhibitors and sponsors
interacted with their customers and growers swapped
ideas on fruit production.
Orchard tours were the main focus as Maureen
explained business history and operations, labor
management practices, and marketing philosophy. She
recounted orchard renovations since 1976 and proudly
displayed their modern, refrigerated and controlled
atmosphere apple storage facilities and modern migrant
labor housing. Additionally, Rich explained numerous
cultural practices that allow for annual production of
65,000 apple and 2,800 peach bushels. A small sample
of Rich's handiwork was a 2001 planting of Scarlet
Spur and Gibson Golds, a 2002 planting of Honeycrisp
and Gala, and a 2003 planting of Gale Gala and
Pioneer Macs.
A further tour stop showed an Imidan
demonstration project conducted by Ohio State
University (OSU) Entomologist, Celeste Welty. This
trial had been established to compare control of codling
moth and plum curculio with the grower's standard
program of mid-level rate of Imidan plus Avaunt and a
high rate of Imidan. According to Celeste, Glen Hill is
not experiencing codling moth control problems, but
data on insecticide efficacy is needed.
Additionally, Dave Gress of Fruit Growers
Marketing Association instructed growers about the
wholesale apple market and described his positive
perspective on an excellent 2003 Ohio apple crop in
quality and quantity.
The final tour stop consisted of a demonstration
of Good Agricultural Practices and Good Handling
Practices by Shari Plimpton of the Center for Innovative
Food Technology. Shari is a food safety educator with
the Ohio Specialty Crop Food Safety Initiative.
Many growers who are subject to the Ohio
Apple Marketing Program's (OAMP) market assessment
had the opportunity for free apple promotional materials
that had recently been developed with funds from
USDA's Specialty Crop Block Grant Program. An
Apple Promotion Display Box with new UPDATED
Ohio Apple Variety Charts and an aluminum Apple
Promotion Display Sign was their reward for attending
the Summer Tour. Betty Eshelman, OAMP chairperson
eagerly dispensed signs to qualifying participants, while
also selling many other Point of Purchase materials to
apple marketers.
The Ohio State University Fruit Team was one
of the many exhibitors and allowed for great interaction
between growers and OSU resource personnel. Another
OSU resource person was John Ellerman, who promoted
the Direct Agricultural Marketing Association's new
marketing website: http://www.farmtomarkets.com.
This website is in addition to the OFGS farm market
resource: http://www.ohiofruit.org. Both sites are
designed to efficiently connect consumers with farm
markets.
The final activity was a program directed by
OFGS President George Lawrence. George introduced
many of the tour VIPs (including 15 representatives of
Ohio State University Extension) and media
representatives, conducted a door prize contest, and
recognized hosts Maureen Buchwald and Rich
Ridenbaugh, sponsors, and exhibitors. Chris Parsons of
the Johnny Appleseed Heritage Center (JAHC) gave a
brief report on the JAHC grand opening in June 2004.
George also announced that the 2004 Summer Tour will
be at the Ohio Agricultural Research and Development
Center in Wooster on June 30. This concluded the 2003
Summer Tour and fulfilled participants expectations as
high as the 90 degree temperatures.
Despite the relatively "unfriendly" weather
patterns for mite development thus far this season, we
have found an increased number of motile forms and
eggs during last week's observations. In most cases
mite numbers are still below the threshold, but with the
possibility of warmer weather in the forecast, it is
critical that growers pay close attention to this pest at
this time of the season.
Since the distribution of mite populations in the
orchard are usually very patchy at this time of the year,
it is important to examine as many trees as possible for
mite presence. Also, select cultivars that are most
sensitive to mite population increases (e.g., Delicious,
Yorking, etc.) If beneficial organisms are present, but
at a level too low to provide adequate mite control,
alternate row middle (ARM) applications of effective
acaricides may be applied. If mite populations are high
(>5-10 mites/leaf) and few or no predators are present,
a complete spray of a miticide may be necessary. The
action thresholds on page 95 of Penn State's Tree Fruit
Production Guide (available on the web at:
http://tfpg.cas.psu.edu/part2/part22bl.htm) are
especially useful, since both Acramite and Pyramite
can quickly bring mite populations down.
To properly assess miticide efficacy, an
evaluation should be made 7-10 days after any miticide
application to determine if any follow up applications
are necessary. Growers should refrain from using more
than one full Acramite or Pyramite application per
season. The other, older summer miticides, such as
Kelthane, Vendex, or Vydate, may still continue to
work well in some orchards depending on previous
usage patterns and resistance. Also, the two mite
ovicides: Apollo (45 day PHI on apples and 21 day PHI
on pears, apricots, cherries, peaces and nectarines) and
Savey (28 days PHI on apples, pears and stone fruit)
are registered for mite control during the summer.
However, these latter two miticides work better on low
mite populations. Similarly, summer oils (i.e., Stylet
oil, Mite e-Oil, Bio-Cover) applied as complete sprays
can also provide satisfactory mite control. If oils are
used in your tree fruit spray program, please read the
labels to comply with the mixing and weather warnings.
In some orchards, especially where a light crop
is expected, it may be a good season to try to re-establish populations of the natural mite predators such
as the Stethorus beetle or phytoseiid predatory mites.
The predators will not establish themselves in orchards
where mites (i.e., their food) are not present, thus the
acceptance of some mites on foliage may actually help
to increase the number of beneficial organisms and
expedite the potential for biological mite control.
Black rot, white rot, bitter rot, sooty blotch, and
flyspeck will all be on the increase as we progress into
the summer months. With all the rain we've had it could
be a banner year for apple rot and smut diseases, as we
(plant pathologists) so affectionately call them. Since I
can no longer remember which fungicides are most
effective for the summer rots, I turn to page 32 of the
2003 Commercial Tree Fruit Spray Guide to check out
the table on effectiveness of fungicides against apple
diseases.
I first note that the SI fungicides (Nova,
Rubigan, Procure and Bayleton) are pretty much
worthless for control of most summer rot diseases. On
the other hand, mancozeb and Polyram are excellent for
control of summer diseases, however they can only be
applied up to 77 days of harvest. After the 77-day to
harvest restriction has passed, captan and ziram remain
our best options for summer cover sprays; they should
be used at the full-labeled rate and on a tight schedule if
cool, wet summer weather prevails.
We also suggest tank mixing with Topsin-M or
Benlate if it turns into a "sooty blotch/fly speck year";
however, Benlate and Topsin-M should be used
sparingly (no more than once a month) to avoid harm to
predator mites and lessen the possibility of the
development of resistance. NOTE: Benlate, and to a
lesser extent Topsin-M, are reported to cause "scarf
skin" if used within 40 days of petal fall. Scarf skin is
a physiological condition in which the fruit surface
develops a milky white or grayish appearance. Scarf
skin has no effect on fruit quality or storage ability, but
impairs the appearance and shine on a red apple. Added
help in control of sooty blotch and flyspeck is now
available with the strobilurin fungicides, Flint and
Sovran. See the following article on Sovran & Flint for
details.
Infection from summer diseases, especially
sooty blotch and flyspeck, can be further reduced
through IPM strategies that lower humidity and
promote rapid drying. These include keeping grass
mowed during summer and keeping trees well pruned.
Tree spacing within and between rows should allow air
movement between all trees. Removing adjacent woods
or cutting breaks in hedgerows will also help improve
airflow in the orchard. Of course it goes without
saying (so I'll say it) that all the above suggestions are
pretty much a waste of time if good sanitation measures
are not strictly followed.
As mentioned above, we now have added help
in control of sooty blotch and flyspeck with the
strobilurin fungicides, Sovran and Flint. In the past we
have suggested a 1st, 3rd, and 7th cover spray program
using Sovran or Flint. This program is based on our
research in which Sovran was applied at the maximum
rate of 1.6 oz per 100 gallons to Golden Delicious at
first cover (May 11th), third cover (June 9th), and
seventh cover (August 3rd). The 1-3-7 program
provided excellent control of both fruit scab and sooty
blotch and flyspeck under extremely high disease
pressure for all diseases. The 3rd and 7th cover sprays
were especially critical in control of sooty blotch and
flyspeck.
Just so there is no confusion, this program is
IN ADDITION TO your regular summer fungicide
cover sprays. We simply are suggesting you substitute
Sovran or Flint for those fungicides you generally use
in the 1st, 3rd and 7th covers. Also, a reminder: WE
STRONGLY suggest no more than three sprays of the
strobilurins per year, and, as the label states, "Do not
apply as the final spray of the season."
Crop load management and thinning of apples
will influence orchard profitability more than any one
of/ or combination of other cultural factors. The two
primary reasons to thin an apple set is for return bloom
the following year and to influence fruit quality during
the current year. Other factors that become crystal clear
in the apple orchard, as the season progresses through to
harvest, include cost control factors.
Handling an evenly-spaced, well-sized crop of
singulated fruit that results from a good thinning job is
the objective. Handling a crop of small apples with 1, 2,
or 3 apples to a spur at harvest can be very costly. An
unthinned crop of apples will normally take 3,000-3,500
apples to fill a bin. A producer can fill a bin with
around 2,000-2,500 apples if the block has been well
thinned. Although the number of bins coming out of a
thinned block and an unthinned block may not vary
much, the value of the fruit in those bins from the two
treatments will vary considerably.
A carefully planned and successful thinning
treatment does not significantly change crop volume.
What you are doing is changing size classes up 2-3
count sizes. Most of the crop should be in that ideal 100
fruit per bushel count size range. A certain percentage
of apples will be larger and a certain percentage will be
smaller. Overall, you end up with fewer apples in larger
size classes filling the same volume of space as a crop of
smaller fruit. The larger fruit normally command a
higher return on the market. The small apples may or
may not be worth more than the price of juice apples.
The last two years have been tough years for
judging outcomes in the orchard and in the marketplace.
Factors including frost influences, moisture deficits, and
lack of seed count in set fruit made management
decisions tough. Most of Ontario's apple acreage this
year has come back with plenty of bloom, and adequate
pollination conditions have existed for the most part.
Steady rains in the second half of May have
influenced pollen movement in some apple blocks that
were in bloom. Aggressive thinning strategies on tough
to thin cultivars are necessary where a decent pollination
has occurred. This may include using more than one
application of thinners and using a combination of
materials. Even with a good degree of success using a
spray thinning program, many cultivars will respond
best with a follow up hand thin to further reduce crop
load.
It is rare to get more than 80% of the set bloom
off the tree with spray thinning on difficult cultivars.
Even though most blocks don't set close to 100%, set on
cultivars like Fuji and some of the Golden Delicious
types can be reduced to only every second king
remaining. This usually means thinning at a 90% rate
and even higher. This includes all the side bloom
fruitlets, plus every second king. How do you know
when you've taken enough off?
Most growers have at one time or another
"sprayed" the crop off the trees of a certain cultivar in
a certain block. This usually results in good judgment
for successive years. Bad experiences tend to make
good judges out of most. It is becoming more difficult
to incorrectly assess a cultivar or block when a
systematic approach is taken in judging tree strength.
Factors influencing tree strength and probability of
response to thinners and to different timings have been
relatively well documented as of late, not only here in
Ontario but throughout the Great Lakes Region in
general.
June is a bad time to judge what a tree canopy
holds for crop just by eyeballing it. With everything
being the same color, fruitlets can hide. Many times I
have seen what looks like nothing remaining in the
canopy only to be fooled at harvest with a very good
crop of well-sized and highly colored fruit.
Ideally, you want to get down to final fruit load
early in the season to influence return bloom the
following year. This is normally done with well timed
early thinning treatments. We have found that fruitlets
will respond to thinners at greater diameters than once
thought. The 8-10 mm timing is the standard to aim for
on a number of varieties. We've had years when we
could not get at the trees because of foul weather and
found that we could get adequate thinning at diameters
up to 12-14mm kings on some cultivars. One of the
factors to a successful response by apple is warm
weather following application of thinners.
For those interested in evaluating the
effectiveness of their management programs directed at
first generation oriental fruit moth (OFM), assessments
should probably begin this week. First generation
OFM larvae attack terminals in both apple and peach
(terminal "strikes"); they will also move into developing
fruitlets in apples (rarely in peach). A single larva may
infest several terminals prior to completing its
development.
Damage to shoots in peaches is readily observed
as terminal "flagging" (Figure 1). The damage can be
confused with brown rot and canker, so be sure to cut
open any suspect terminals and look for the presence of
both larvae and frass (insect excrement). In apple,
terminals do not show obvious flagging (Figure 2); close
examination is required (Figure 3). A larva may or may
not be present within the terminal (Figure 4).
Damage is often higher in border areas. Do not
bias your counts toward "hot spots" in the orchard. In
peaches, assessments should include examination of 100
terminals per tree, from 2.5% or 5 trees per acre. Count
the number of terminal strikes. Walk-throughs are often
useful in establishing "hot spots" within the orchard.
There is no well-established protocol for apple; however,
we recommend examining 50 terminals and 50 fruitlets
per tree, at a rate of 5 trees per acre (standard block).
The goal is to obtain a representative sampling of
damage in the orchard block(s). Preliminary data
indicates varietal preferences by OFM in apple.
Damage in excess of 1-2% following first
generation may indicate potential failure of the program
(poor efficacy, problems with timing, resistance, other).
It is important to note, however, that first generation
strikes are really only providing an indication that some
OFM infestation of the crop has occurred - essentially
they are an early warning and not a good indicator of
future damage levels. To reduce damage to the fruit by
subsequent generations, carefully review pest
management programs with a qualified crop consultant.
Ohio Location
Site: Waterman Lab, Columbus
Site: Medina, Wayne, & Holmes Counties
Apple: 6/18 to 6/25/03
Peach: 6/18 to 6/25/03
Site: East District: Erie & Lorain Counties
Other pests: green apple aphid, rosy apple aphid
Beneficials: green lacewing, ladybeetle, white maggot,
and orange maggot
Site: West District: Huron, Ottawa, Richland, & Sandusky Counties - Gene Horner, IPM Scout
Other pests: TSSM, RBLR damage
Beneficials: banded thrips, lacewing, predatory mite
Ted W. Gastier Effect of Rain on Fungicide Wash-Off
Source: Bruce Bordelon, Purdue Horticulture, Facts for Fancy Fruit FFF03-07
OFGS Summer Tour a Success
Source: Tom Sachs, Executive Director, Ohio Vegetable and Potato Growers Association (OVPGA) & Ohio Fruit
Growers Society (OFGS)
Mite Control Update
Source: Fruit Times, June 17, 2003, Vol. 22, No. 9
A Banner Year for Apple Summer Diseases
Source: Paul Pecknold, Purdue Plant Pathologist, Facts for Fancy Fruit, FFF03-07
Sovran & Flint for Control of Sooty Blotch & Flyspeck
Source: Paul Pecknold, Purdue Plant Pathologist, Facts for Fancy Fruit, FFF03-07
Apple Crop Load Management
Source: John Gardner, Apple Specialist, Ontario "Hort Matters" Volume 3, Issue 12, June 11, 2003
Checking for Oriental Fruit Moth Damage in Apples and Peaches
Source: Hannah Fraser, Entomology Program Lead-Horticultural Crops, Ontario HortMatters, Volume 3, Issue
13, June 18, 2003
Degree Day Accumulations for Ohio Sites June 25, 2003
Degree Day Accumulations
Base 45° F
Base 50° F
Actual
Normal
Actual
Normal
Akron/Canton
1200
1256
776
876
Cincinnati
1545
1722
1082
1253
Cleveland
1190
1208
787
842
Columbus
1480
1445
1026
1030
Dayton
1407
1484
963
1068
Kingsville
969
1097
601
759
Mansfield
1124
1235
708
861
Norwalk
1146
1205
744
845
Piketon
1631
1711
1135
1234
Toledo
1135
1195
734
838
Wooster
1295
1172
860
805
Youngstown
1059
1137
654
779 Pest Phenology
Coming Event
Degree Day Accum. Base 50° F
Lesser peachtree borer flight peak
392 - 1526
Lesser appleworm 1st flight
subsides
449 - 999
Apple maggot 1st catch
629 - 1297
Redbanded leafroller 2nd flight
begins
656 - 1381
Codling moth 1st flight subsides
673 - 1412
Spotted tentiform leafminer 2nd
flight peak
701 - 1355
Oriental fruit moth 2nd flight begins
772 - 1215
Codling moth 2nd flight begins
864 - 1549
San Jose scale 2nd flight begins
893 - 1407 Fruit Observations & Trap Reports
Dr. Celeste Welty, OSU Extension Entomologist
Ron Becker, IPM Program Assistant
STLM: Holmes: 1790 (down from 2147) Medina: 1365 (up from 1105) Wayne: 240 (down from 424) RBLR: Holmes: 16.7 (up from 0) Medina: 6.5 (up from 0) Wayne: 10.7 (up from 0) CM: Holmes: 2.6 (down from 4.1) Medina: 0.6 (down from 1.7) Wayne: 27.0 (down from 41.9)
LPTB: Holmes: 15 (up from 10) Medina: 0 (down from 3) Wayne: 0 (down from 5) OFM: Holmes: 0 (down from 3) Medina: 0.5 (up from 0) Wayne: 0 (same as last week) PTB: Holmes: 0 (same as last week) Medina: 0 (same as last week) Wayne: 0 (same as last week)
Jim Mutchler, IPM Scout
The Ohio Fruit ICM News is edited by:
Extension Agent, Agriculture
Tree Fruit Team Coordinator
Ohio State University Extension Huron County
180 Milan Avenue
Norwalk, OH 44857
Phone: (419)668-8210
FAX: (419)663-4233
E-mail: gastier.1@osu.edu
Information presented above and where trade names are used, they are
supplied with the understanding that no discrimination is intended and no endorsement by
Ohio State University Extension is implied. Although every attempt is made to produce
information that is complete, timely, and accurate, the pesticide user bears
responsibility of consulting the pesticide label and adhering to those directions.
Copyright © The Ohio State University 2003
All educational programs conducted by Ohio State University Extension
are available to clientele on a nondiscriminatory basis without regard to
race, color, creed, religion, sexual orientation, national origin, gender,
age, disability or Vietnam-era veteran status.
Keith L. Smith, Associate Vice President for Ag. Adm. and Director,
OSU Extension.
TDD No. 800-589-8292 (Ohio only) or 614-292-1868