SW Michigan Fruit Update
Southwest Michigan, March 31, 2008
Weather
Spring was delayed by a snowstorm on Good Friday, March 20. The storm dumped 6 to 14 inches of snow in the region. The heaviest snow fell in Van Buren County. The snow on Good Friday, the first full day of Spring, brought to mind the Easter freezes of 2007. Easter was April 8 in 2007, more than 2 weeks later than in 2008. In 2007, the fruit crops were advanced by a week of warm weather before the freeze and this year temperatures have been cool delaying bud break.
Growing Degree
Day (GDD) accumulations are behind most of the last 10 years in Growing Degree Days.
Bill Shane reports that the GDD42 total for 2008 (68) through March 31st since Jan 1 at
SWMREC is ahead of 2001 (34), similar to 2005 (67), but behind all other years starting
from 1995. So we are in the 2nd coldest spring in the last 14 years. Growing
Degree Day accumulations this early in the year move in fits and starts, with several warm
days causing a rapid rise and then a long plateau caused by cooler weather. The
current La Nina weather pattern will probably keep warmer weather away.
The weather last week was cool, with highs in the 40s and lows below freezing. The snow melts quickly when the sun is up for more than 12 hours. Most of the snow from Good Friday’s storm had melted by late last week and ice had melted off the lakes and ponds. More snow last Thursday also melted quickly. Buds are beginning to swell. There is little danger of spring freeze damage at this time. We would need temperatures well below 20F to cause damage at this time. When buds become noticeably swollen temperatures in the low 20s will cause damage but that seems unlikely for a few weeks.
Wide spread rain fell Monday and soils are saturated.
Southwest
Michigan Growing Degree Day Totals
|
Grapes, from April 1 |
|||
Location |
GDD 42 |
GDD 45 |
GDD 50 |
GDD 50 |
33 |
18 |
6 |
0 |
|
31 |
17 |
4 |
0 |
|
25 |
13 |
3 |
0 |
|
25 |
13 |
4 |
0 |
|
18 |
8 |
2 |
0 |
|
23 |
12 |
2 |
0 |
|
28 |
15 |
4 |
0 |
|
19 |
11 |
3 |
0 |
|
17 |
7 |
2 |
0 |
|
Tree fruit
Tree fruits are starting to show some movement. Growers have reported
some movement in apricots, peaches and Japanese plums. Growers still have the opportunity
to apply dormant sprays to
reduce overwintering disease inoculum.
Apricot buds are beginning to swell.
Peaches buds are swelling. No green tissue is exposed. Most growers still have time to apply sprays to control peach leaf curl.
Both sweet and tart cherriesare showing some movement. Copper can still be applied to sweet cherries as a dormant spray to reduce bacterial canker.
In Plums, Oriental plum buds moved last week during the warm weather but European plums are show little movement.
Apples show little movement. Growers need be ready for apple scab. Because of the mild winter, we expect scab spores from the leaf litter will be ready as soon as green tissue is available for infection. Growers should be ready to apply scab sprays.
Pears buds are dormant. Pear Psylla adults should emerge soon when warm weather returns.
Small
fruit
Small fruit appear dormant. Now is the window for Lime Sulfur applications in blueberries, grapes and brambles to suppress diseases that overwinter on the plant.
Blueberry fruit buds show little if any swelling and leaf buds have not moved. It is too early to look for mummyberry mushrooms. Mushroom development should begin about the time green tissue shows on the leaf buds. We really need several warm days to warm up the soil.
Grape buds are tight and dormant. Some of the wood in juice grape vineyards looks weak from the large crop last year.
Strawberries are beginning to green up, but new leaves have not yet begun to emerge. Growers are applying herbicides and putting down straw mulch.
Raspberries are dormant. Now is the window for Lime Sulfur applications to suppress anthracnose.
Cranberries are dormant.
Miscellaneous
Growers are pruning and clearing brush.
The first Monday Fruit Update meeting will be, Monday April 7, at the Fruit Acres Farm in Berrien County.
Southwest Michigan, 2008 Fruit IPM Meetings
The Monday Fruit IPM update meetings will be at Annette and Randy Bjorge’s Fruit Acres in Berrien County again this year. The weekly meetings will begin on April 7 and run until July 10. There will be no Monday meetings on Memorial Day, May 26. The meeting will run from 5 to 6:30 PM. Each meeting will be a review of the current fruit pest situation in Berrien County with displays of insects and fruit collected that day from area fruit plantings. Bill Shane, Greg Vlaming and Mark Longstroth will share the results of their scouting and discuss current and upcoming pest events and emergences. (Each week will change with changing pest complex). The meeting dates are April 7, 14, 21, 28, May 6, 12, 19, June 2, 9, 16, 23, July 7, 21, August 4 and August 18. One RUP credit is available for private pesticide applicators and commercial with a fruit certification (1C).
