FFF04-03 April 23, 2004

Crop Conditions: Very warm temperatures over the past week pushed
plants quickly. Grapes are at bud break to 6-inch shoots, depending on
location. Strawberries are in bloom in central areas and growers should
scout for eastern flower thrips after the strong winds of the past
week.  Bloom in apples has come (and in many places gone) quickly.
Regarding effects on pollination, rain during bloom may have been
offset by warmer than usual temperatures.

Care of New Trees:  If you planted new trees this spring, a few points
to remember to help them get off to a good start. _ Heavy pruning on
young trees delays the time when cropping begins.  So to bring trees in
to cropping early, minimal pruning should be done in the early years. _
Make sure the graft union is a few inches out of the soil to reduce the
chance of scion rooting. _ If planting dwarfing trees, provide a post
or trellis as tree support right from the time of planting. _ Pay
attention to weed control. Weeds can severely impact the establishment
of young trees. _ If deer are likely to be a problem, apply control
measures from day 1 (deer fence, soap, etc). _ Even though trees wonÕt
have fruit the first year, good pest and disease control is essential.

Remember, your goal is not for the trees to just survive (although that
is definitely a good start!), but to have them perform close to the
optimum.  (Hirst)

New this spring for Grape Growers: Michigan State University has been
working with the National Grape Cooperative and the Michigan Wine
Industry to bring you a new resource for integrated vineyard
management. Visit http://www.grapes.msu.edu/.  This is a great new
resource for grape growers in our region. The website compliments the
new publication A Pocket Guide for Grape IPM Scouting in the North
Central and Eastern U.S. that Michigan State University published this
past year. Details for ordering the publication are available on the
website.

What to Consider for Spring Grape Disease Management: Disease history
of the vineyard: Most vineyards do not have a history of all grape
diseases. Growers should focus their disease control efforts on the
diseases they know are a problem for them. Disease pressure depends on
the weather conditions, the cultivar grown, the age of the vineyard,
the location, and the training system. For instance, humid weather is
more conducive to powdery mildew, and hedged vineyards typically have
more Phomopsis than hand-pruned vineyards. (Annemiek Schilder, Michigan
State University)

Cleanup of vineyard: Prune out dead canes and stubs as much as possible
since they are the main sources of Phomopsis spores. Remove any fruit
mummies still hanging on the vine, since these may release black rot
spores. Also remove large pieces of wood from the vineyard and burn
them. This is especially important in Eutypa-infected vineyards, since
dead wood remains a source of Eutypa inoculum for multiple years. While
it is recommended to remove pruned canes from vineyards, most growers
find it more practical to chop them up. This may be okay, provided that
the canes are well pulverized so that they can decompose quickly. Make
two passes with a brush- chopping mower if necessary.

Timing of disease control measures: Timing of disease control measures
is critical to success. Protectant fungicides have to be used before an
infection period occurs. Between one and five inches of shoot growth,
Phomopsis cane and leaf spot is the primary disease of concern.
Clusters and shoots are vulnerable as soon as they become exposed.
Young tissues are most susceptible. Spray timing trials have indicated
that this stage is important for controlling cluster stem (rachis) and
shoot infections. Wet weather conditions during this period of rapid
shoot elongation are ideal conditions for the infection and spread of
Phomopsis. Applications should be made 10 days to two weeks apart,
depending on weather conditions. If there are frequent rain events
(several per week, with rainfall totals greater than one inch since the
last spray) then the spray interval should be 10 days. Protectant
materials will protect the shoots and leaves for two weeks if rain
events occur weekly with rainfall totals less than one inch since the
last fungicide application. Powdery mildew control should not be
delayed in vinifera and susceptible French hybrid vineyards past the 10
to 12 inch growth stage. However, in most Concord vineyards, powdery
mildew control is not imminent at this time. Phomopsis is still the
primary concern at this stage of growth. Black rot may be an issue in
vineyards that had a problem the previous year. There is an abundance
of succulent tissue that is highly susceptible to infection. In
addition, the clusters are also exposed to infection at this stage.
Extended periods of wet weather are very favorable to most grape
diseases. In general, if the leaves and shoots are wet for eight hours
or longer, infection is possible if not protected by a fungicide.

What fungicides to use early in the season? The fungicides most
effective in controlling Phomopsis are also effective in controlling
early season (foliar) black rot. The broad-spectrum fungicide mancozeb
(Dithane, Manzate, Penncozeb and Manex) is the most effective material
for controlling these diseases early in the season. It is recommended
to save the use of SIÕs (e.g., Nova and Elite) and strobilurins (e.g.,
Abound, Sovran, Flint) until later in the season when they are needed
for control of multiple diseases. Both of these groups of fungicides
are prone to resistance development, so are best used at critical
disease control periods (immediate prebloom until second postbloom). Do
not use these materials more than three times per season regardless of
the material. Rotating these two fungicide groups can help delay the
development of resistance. JMS Stylet Oil or sulfur may be used to
control powdery mildew early in the season. However, powdery mildew
generally is not a great concern at this time, except in susceptible
cultivars and vineyards that had a problem with fruit infection the
previous year. Resistance development to these materials is not a
concern, but there are some compatibility restrictions with Stylet Oil
and other spray materials. Read the label for details. Do not apply
sulfur to sensitive varieties.

Use of dormant sprays: Delayed dormant sprays (before budbreak) have
shown promising results for Phomopsis control in Michigan. We observed,
on average, a 50 to 60 percent decrease in disease severity on the
grape leaves as well as clusters from a single dormant spray of Topsin
M, lime sulfur, sulfur, Stylet oil, or copper (Kocide) at budswell.
Tank mixing Sulfur and Stylet oil did not increase control; rather the
combination was worse than each product used singly. A single dormant
application with a sulfur or copper product appeared to be the most
inexpensive of the treatments tested. If no green tissue is showing,
these products should be safe on sulfur or copper sensitive varieties.
At this time, only lime sulfur and copper products are explicitly
labeled for use as dormant sprays in grapes. The labels on sulfur
products are somewhat ambiguous on dormant use. We will be evaluating
these and various other products again as dormant sprays in 2004, as
well as reduced spray programs in combination with dormant sprays.
(Source: Fruit Crop CAT, Vol. 19, No. 2, April 13, 2004)

Fire Blight: The best prevention for fire blight is the application of
streptomycin during bloom. Apply streptomycin just as blossoms begin
opening and repeat every 3-4 days if weather favorable for blossom
blight infection persists. Streptomycin is most effective when applied
the day before or the day of an infection event.  The ÒMARYBLYTÓ
computer software program will help you in determining when and if an
infection event occurred as well as predict the risk for future
infection periods.  We strongly recommend its use for those growers at
high risk.  Speaking of high risk, be especially diligent in your fire
blight program if you have blight susceptible varieties (Ida Red,
Jonathan, Gala, Rome, Lodi, etc.) in combination with M-26, M-9 and/or
Mark rootstocks and/or interstems.  These DYNAMITE combinations have
the potential to explode into rootstock blight, which usually means a
dead tree!

Apple Scab:  The peak period for scab infection is NOW!  Primary scab
spores are ripe and ready to infect, all they need is a good scab rain.
 Are you prepared?  For growers on a curative schedule, or for those
who get caught with their pants down (unprotected), we suggest Nova,
Flint, or Sovran.  These fungicides will provide up to 96 hours
Òcurative activityÓ.  However, the sooner you apply them the better! Do
not sit around thinking there is no need to rush.  NOTE: see comments
below on the Strobilurins.

Rust Diseases:  Cedar apple and cedar quince rust are now actively
infecting foliage and fruit. Except for the northern areas of the
state, we are now into the peak period for rust infection.  The
sterol-inhibiting fungicides, Nova and Rubigan, are excellent in
preventing rust problems, as well as providing excellent control of
powdery mildew, which is also infecting new leaf tissue, right now!

Nova, Rubigan & Tank Mixes: All Nova or Rubigan applications should be
tank-mixed with a standard protectant fungicide to avoid problems with
resistance to apple scab.  However, it is especially important that
your final spray (petal fall or first cover) of Nova or Rubigan be
combined with a protectant fungicide such as captan, ziram, mancozeb,
or Polyram.  The addition of a protectant fungicide at this time will
help provide protection from summer diseases such as black rot, sooty
blotch and fly speck and also give added protection from fruit scab.
Refer to Rubigan and Nova labels for additional information on tank
mixes.

The Strobilurins:  The strobilurin fungicides, Sovran and Flint, are
excellent in control of many diseases. Unfortunately they are also very
prone to the development of resistance.  Therefore growers should be
extremely judicious in their use of these compounds.  We suggest you
consider the use of Flint or Sovran in ONLY the FIRST, THIRD and
SEVENTH cover sprays (three times only) for control of fruit scab and
sooty blotch and flyspeck (SBFS).  Our field trials this past year
confirmed our previous findings that Sovran, applied at the full rate,
gives excellent control of both fruit scab and SBFS when applied at
these three times (first, third and seventh cover).  While the
strobilurins are effective in precover sprays for the control of other
diseases, we believe their real strength lies in the control of fruit
scab and sooty blotch and flyspeck. So lets use them when they will do
the most good and hopefully avoid future resistance problems.

ÔOvationÕ Strawberry Released by USDA-ARS at Beltsville, MD: The
ÔOvationÕ strawberry is large, firm, attractive, and has a very late
fruiting season. It has resistance to red stele and is little affected
by most foliage diseases, although it does show some powdery mildew
after fruiting. Anthracnose plant disease has not been observed on
plants in the field, but growth chamber studies indicate that infection
is possible under conditions favorable for development. Yields in
Maryland, Ohio, and Pennsylvania in the plasticulture production system
have been outstanding and ÔOvationÕ is an excellent variety to follow
Chandler. In the traditional matted row-system, ÔOvationÕ has been the
top yielding late season cultivar in Ohio and New Jersey. It has been
average to below average in Maryland trial yields, however fruit size
and appearance have been excellent. Although we have not evaluated this
cultivar in Indiana, varieties that have been released from the USDA
breeding program in Maryland have generally done very well for us.
(Bordelon)

Strawberries and Botrytis Fruit Rot:  The most important sprays for
control of Botrytis fruit rot (gray mold) of strawberry are those
applied at bloom - starting at 10% bloom.  There have been some major
changes in fungicide registrations for Botrytis control in
strawberries.  Ronilan and Rovral can no longer be used on
strawberries.  Elevate received registration in 2000, and Switch
received registration in 2002.  Both should provide excellent control
of gray mold.  So, the options for Botrytis control are Elevate,
Switch, and Topsin M.  None of them should be used alone for
season-long control of Botrytis because of the potential for
development of resistant pathogen strains. See ID-169, 2004 Indiana
Commercial Small Fruit & Grape Spray Guide,
(www.hort.purdue.edu/hort/ext/sfg) and the Midwest Small Fruit Pest
Management Handbook (www.ag.ohio-state.edu/~sfgnet/) for complete
discussions of strawberry IPM. (Pecknold and Bordelon)

Eastern Flower Thrips:  One of the factors we believe may be associated
with problems with eastern flower thrips on strawberries is having
sustained, strong southerly winds early in the growing season. Such
winds may blow eastern flower thrips to Indiana from southern areas.
Considering the very strong winds we had this past week, it would be
prudent for strawberries growers to watch for thrips as we approach
bloom. We recommend looking at the early flowers, especially on early
varieties.  Although an exact threshold has not been established for
Midwest conditions, data from elsewhere suggest that control is
warranted if counts exceed 2 to 10 thrips per blossom. This is a wide
range, but more precise information is not available. Lorsban or
Thiodan are probably the best choices among conventional insecticides,
and Brigade and Danitol or SpinTor also are likely to work well.
Growers may also want to consider using an insecticide containing neem
extracts (Align or Neemix) that is less toxic to bees. (Foster and
Bordelon)

New supplemental label for Sinbar:  The hebicide Sinbar has recently
received a supplemental label for newly planted and non-bearing fruit
trees.  Contact your agricultural chemical supplier for more
information.

E-mail Groups Available for Indiana Growers:  WeÕd like to remind you
about the two mail groups for Indiana fruit and vegetable growers,
winemakers, farm markets, etc. as part of our Fruit and Vegetable web
site. The project is sponsored by the Purdue University Department of
Horticulture and Landscape Architecture and was partially funded by a
USDA Specialty Crop Block Grant through the Office of the Indiana
Commission of Agriculture. The ÒFruitvegÓ group is for all fruit and
vegetable growers, farm marketers, etc. in Indiana and surrounding
states.  The ÒWinegrapeÓ mail group is primarily for the Indiana wine
industry. Anyone can subscribe to either group.  These mail groups are
free and open for all to use.

The mail groups have been established to allow Indiana fruit and
vegetable growers, wine grape growers and wineries, and farm marketers
to interact with each other electronically. We envision growers and
marketers using this forum for free and open exchange of information
and ideas. We also feel that the list can be used to coordinate group
purchases of equipment and supplies, and as a forum to buy and sell
produce and used equipment and supplies. However, we believe that
advertising by commercial vendors is not appropriate use of the mail
group. While we do not intend to moderate the list, we will keep an eye
on the activity. We will not allow personal vendettas, inflammatory
comments or other inappropriate use of the list. Any statements made do
not represent ÒofficialÓ opinions, and Purdue University takes no
responsibility for content. Remember that all messages sent into the
mail group are distributed to everyone on the list, therefore it is not
intended for private communication between 2 individuals.

There are two ways to receive messages from the mail groups, as a list
or a digest. If you subscribe to the mailing list, each message that is
sent to the list will be forwarded to you as a separate e-mail message.
For example, if there are 5 messages sent to the list in one day, you
will receive 5 e-mails from the list that day. Subscribe to the mailing
list using this option if you want to receive messages as soon as they
are posted. If you subscribe to the mailing list digest, all messages
received by the list in one day will be combined into one e-mail
message and sent to you periodically. If there are 5 messages sent to
the list in one day, you will receive one e-mail containing all 5
messages. Subscribe to the mailing list using the digest option if you
prefer to receive fewer separate e-mail messages.

To subscribe to the list, send a message to <majordomo@purdue.edu> with
the following command in the body of your email message:

    subscribe fruitveg or
    subscribe winegrape

or if you prefer the digest option, send a message to
<majordomo@purdue.edu> with the following command in the body of your
email message:

    subscribe fruitveg-digest or
    subscribe winegrape-digest

You will receive a message back from majordomo requiring authentication
of your subscription. The process is quick and self-explanatory. If you
have any problems, let one of us know and weÕll try to help.

Health Update:  In addition to the health benefits we already know
about, eating more fruits and vegetables may also help fight bacterial
infections.

Flavonoids Ð antioxidants found in fruits and vegetables Ð have now
been found to stop the growth of some strains of drug-resistant
bacteria.  Previous studies have shown flavonoids can help guard
against allergies, inflammation, viruses and some cancers. (from
Phytotherapy Research via Hope Health Newsletter).

Upcoming Meetings:

April 28 Ð Northeast Indiana Fruitgrowers twilight meeting.  Fairland
Orchard.  For more information contact Ricky Kemery, Phone
219-481-6826, email ricky.kemery@ces.purdue.edu

April 29 Ð Fruitgrowers twilight meeting.  Sunrise Orchards, Goshen.
6.30 pm.  Contact Jeff Burbrink for more details (Phone 219-533-0554,
email jeff.burbrink@ces.purdue.edu)

May 4 Ð Eastern Indiana Fruitgrowers Twilight meeting.  Hosted by Wayne
Jacobs (formerly Rex AndersonÕs Orchard).  4676 N 75 W New Castle IN.
Contact Dave Clamme for more details (Phone 765- 747-7732), email
dclamme@purdue.edu

May 5 Ð Twilight Meeting, County Line Orchard, 6.30 pm.  Directions at
the County Line Orchard website (www.countylineorchard.com), or contact
Stan Sims (Phone 219-755-3240)

June 21 Ð Indiana WinegrowersÕ Guild summer meeting & workshop. Chateau
Pomije Winery, New Alsace. Visit www.indianawines.org for details.