SW Michigan Fruit Update

Check the Index for earlier postings

Southwest Michigan, April 22, 2008

Mark Longstroth, Bill Shane, Greg Vlaming

Weather

Warm temperatures with highs in the 70s and lows near 50 increased plant growth.  Some rain fell in the Berrien County and the southwest portion of the region Saturday.  With the warmer weather, our GDD accumulation has moved much closer to average.  We are still behind recent years, but are no longer unusually cool.  Continued warm weather should place us in the middle of the average spread of GDD.  The warm weather makes freezes seem unlikely, but we are only about half way through the spring freeze season.  There is now a wide range in bud stage development.  Freeze injury would occur at temperatures from freezing to the low 20s.  Soils are beginning to dry out.  The forecast is for continued warm and dry conditions with rain showers Friday.  I changed the links below to the Enviroweather webpage for the automated weather stations.  This will allow you to quickly find information of the weather station closest to you.

Southwest Michigan Growing Degree Day Totals March 1 through April 20, 2008				Grapes, from April 1
Location	GDD 42	GDD 45	GDD 50	GDD 50
Berrien Springs:	219	163	98	88
Scottdale:	206	154	90	82
SWMREC:	194	145	86	80
Bainbridge:	201	151	91	84
Hartford:	184	138	84	80
Lawton:	214	164	101	96
Grand Junction:	215	162	99	93
South Haven:	171	129	77	70
Fennville:	165	120	69	65

Tree fruit

Tree fruit buds are nearing bloom.  Insect activity increased last week.  Oriental Fruit Moth has not been trapped yet.  Redbanded leafroller are flying.

Apricots are blooming.   

Peaches buds are at pink for early showy varieties and red calyx for non-showy varieties.  Now is the time to put out pheromones for Oriental Fruit Moth for mating disruption.  Mating disruption has been very successful against this pest.  The first generation attacks the growing shoot tips.  We expect to catch Oriental Fruit Moth any day now.

Sweet Cherry buds generally are at green tip and the buds are about to open.  Early varieties are at first white. 

Tart Cherry buds generally are at green tip or tight cluster.  Copper can still be applied to tart cherries, if which can tolerate copper very well.

In Plums, Japanese plums are at white bud.  European plums are at green tip to tight cluster. 

Apples buds are beginning to open.  Early varieties are at tight cluster.  Rain on Saturday was an apple scab infection for many areas in and around Berrien County.  The wetting period and the temperature were marginal for some areas with the wetting period being a little short for the temperature, so infection could easily have occurred in your orchard if it was wet longer or a little warmer.  Many growers were applying material with back action Sunday and Monday.

Pears buds are at tight cluster but have not started to open.  Pear psylla are laying eggs.  .

Small fruit

Blueberry fruit buds are open and leaf buds are ¼ to ½ green and beginning to open.  Mummyberry mushrooms are out.

Grapes are at scale crack to first swell.  Both juice and wine grapes are at similar development stages.  At this bud stage, injury would occur at temperatures in the low 20s.  There is still time to apply dormant sprays of copper, sulfur or lime sulfur.

New strawberry leaves are unfolding and flower trusses are visible in the crown.  .

Raspberry and Blackberry leaves are unfolding and new primocanes should emerge soon.  The window for Lime Sulfur applications to suppress anthracnose is over.

Cranberry beds are coloring up and the tip buds seem to be expanding.

Miscellaneous

As the soil dry out, growers are working fields and planting trees.

The next Monday Fruit Update meeting will be, Monday April 28, at the Fruit Acres Farm in Berrien County.