SW Michigan Fruit Update

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Southwest Michigan Fruit Update, July 30, 2007

Mark Longstroth, Bill Shane, Greg Vlaming

Weather

The last two weeks have been hot and dry.  Highs have been in the 80s with lows in the 60s.  Scattered storms passed through the region last week dropping an inch or more of rain, close to the lake.  Berrien County received heavy rain.  Very little rain fell away from the lake.  Fruit crops continue to show signs of drought stress.  Soils are very dry.  The forecast is for hot, dry weather.  The dry conditions this season have resulted in very little disease pressure in most fruits.

Southwest Michigan Growing Degree Days (GDD) Totals March 1 through July 29, 2007				Grapes from April 1
Location	GDD 42	GDD 45	GDD 50	GDD 50
Scottdale	2841	2481	1924	1817
SWMREC:	2746	2389	1839	1741
Bainbridge:	2670	2319	1778	1607
Hartford:	2576	2226	1689	1594
Lawton	2831	2433	1913	1810
South Haven	2541	2195	1665	1572
Fennville:	2525	2177	1644	1564

Insects

Japanese beetles are common. 

Tree fruit

Peach growers are harvesting Red Haven, PF12A, Starfire, Blazingstar, and Redstar.  There is light thrip damage in some orchards but nothing serious.  Oriental fruit moth catches have been declining indicating the end of the second generation.  The third generation should emerge at about 2400 GDD base 45, so pheromone lures should be changed in the next two weeks.  San Jose scale damage to nectarine fruit was seen in our area.

Cherries look good with little sign of cherry leaf spot.

In Apples, Cork spot is showing up on early apple varieties.  Paulared harvest is about 10 days away for the lower part of the SW region and Gala harvest is projected to begin about August 24^th.  Retain applications go on approximately 4 weeks before anticipated harvest to control pre-harvest drop and to delay fruit maturity.  NAA timing for controlling pre-harvest drop is about 7-10 days before anticipated harvest.  Codling moth trap catches jumped up for most monitored apple orchards in SW, even those with relatively light pressure.  This increase is a strong flight by the second generation.  Biofix for high-pressure sites was July 14^th and lower pressure site biofix was approximately July 21^st.  European red mites numbers are high in some orchards.  Fungicides should be included in cover sprays to control sooty blotch and fly speck.

Pear fruit needs to be protected from the second generation of codling moth.  European red mites do not bronze the leaves of pears but turn them black.

Small fruit

Blueberry harvest continues.  Currently we are picking Bluecrop, Jersey and Elliot.  Growers are irrigating to maintain fruit size.  Sprinkler irrigation is conducive to fruit rot development and fungicide protection is very important in these fields. Anthracnose and Alternaria can be found.  Blueberry maggot is flying in some areas.  Japanese beetles and blueberry aphids are out.  Be sure to check the new Blueberry IPM Newsletter at the MSU Blueberry Site. 

Grape veraison has begun in early ripening varieties such as Foch, Reliance, and Himrod.  Grape berry moth trap catch numbers are up.  The second-generation flight is underway.  Japanese beetle and grape leafhopper numbers are building.  Backyard growers are reporting heavy losses to black rot.  By now the berries on most varieties are resistant to grape diseases.  Phomopsis berry rot and drop has begun on early ripening varieties.  A botrytis bunch rot spray is timed for veraison in wine and table varieties. The final grape IPM scouting meeting will be Thursday, August 9, at Lemon Creek Vineyards, west of Berrien Springs at 6 PM.  Check the MSU Grape website for scouting updates.

Strawberry growth is good where irrigation has been used and potato leafhopper controlled. 

Raspberry harvest is ending.  Japanese beetles and potato leafhopper are easy to find. 

Plum Pox Update

Mike Hansen, Region 5 Supervisor, Michigan Department of Agriculture

Plum Pox sampling in SW Michigan is progressing well. The MDA sampling teams collected their 40,000th SW MI sample of the summer on July 31.  All orchards located within 5 miles of last years positive find as well as farms from across Berrien, Van Buren and Allegan County are being sampled in SW Michigan this summer. Sampling will continue through Mid August.  Additionally, MDA is looking at stone fruit statewide with another sample team collecting samples in West Central Michigan, primarily in Mason and Oceana Counties. 

Samples are collected and processed at the MDA and MSU laboratories in East Lansing within 7 days of collection. Samples from SW are going to the MDA lab, while samples from West Central are going to MSU. All results reported out of the labs have been negative in 2007.