Northern Michigan FruitNet 2009
Weekly Update
NW Michigan Horticultural Research Station
| Nikki Rothwell District Horticulturist |
Erin Lizotte District Fruit IPM/IFP Agent |
Bill Klein Farm Mgr, NWMHRS |
| Duke Elsner Agricultural & Regional Viticulture Agent |
July 21, 2009
GROWING DEGREE DAY ACCUMULATIONS AS OF July 20th AT THE NWMHRS
Year |
2009 |
2008 |
2007 |
2006 |
2005 |
2004 |
19yr. Avg. |
GDD42 |
1644 |
1785 |
2082 |
2096 |
2146 |
1648 |
1874.2 |
GDD50 |
949 | 1097 | 1326 | 1324 | 1409 | 954 | 1170.6 |
Weather Report
The end of last week was unseasonably cool, but the start of this week seems more summerlike. Although rain is predicted in all days of this week, we have not had any rainfall since we received a small amount of rain (0.14 inches) on 17 July. The last significant rainfall was on 11 July where we received just under a half inch of rain. The total amount of rainfall this season is 9.65 inches; last year at this same time, we had 16.3 inches of rain. As far as growing degree days (GDD), we have accumulated 1644 GDD base 42 and 949 GDD base 50. These numbers still trail our 19-year average by 152 GDD (base 42) and 121 GDD (base 50).
Crop Report
Pears are at 30-39mm, and apricots are at 40mm in size. Apples range from 39-42mm. Montmorency cherries are 19mm and Balatons are 20mm in size. Sweet cherries are at 20-23mm in size. Stem-on sweet cherry harvest continues in the northern most areas of the region while traditional sweet cherry harvest is underway in the southern regions. Fruit appears to be in good shape although few cracks are evident. Ethephon has been applied to many tart cherry blocks, and harvest is predicted to start in Benzie/Manistee Counties this weekend. We estimate we will harvest in 7-10 days here at the research station.
Pest Report
Apples. Spotted tentiform leafminer numbers are increasing, and we found almost 200 on one trap this week. Codling moth (CM) numbers continue to be low, and we caught an average of one moth/trap this week. Perhaps with the warmer temperatures predicted, we will see an increase in CM flight. Obliquebanded leafroller (OBLR) numbers are increasing, and we caught 13 in one trap and 5 in another trap this week. However, we have observed OBLR in many stages throughout the orchards: a few large caterpillars, likely 5th or 6th instar, multiple pupae and many pupae where moths have emerged. OBLR development is all over the board this season, likely due to cool temperatures. Very few oriental fruit moths were caught this week, and apple maggot traps have been placed into blocks this week.
Cherry. Obliquebanded leafroller numbers are high in tart cherry blocks, where we have caught 46, 10, and 26 moths in three traps in three different orchards. We have also been counting OBLR in sweet cherry blocks, and these numbers are also high. This pest is particularly worrisome as we approach sweet cherry harvest, and many larvae/pupae are evident in sweet cherry clusters. Growers should be on the lookout for these pests this season. Lesser peachtree borer numbers are moderate (average of 9/trap). Greater peachtree borer numbers are similar with an average of 9 moths/trap. American plum borer numbers are a bit higher with 14 moths per trap. This insect has two flights per season, and often this second flight peaks at the time of cherry harvest. Cherry fruit flies are evident in many area orchards, and we want to stress that growers should be trapping for these insects in their individual orchards as the numbers of flies are higher than anticipated in many blocks.
Winegrapes. Grapes continue to grow, and many regional vineyards are at buck shot berry. Grape berry moth is still present in a few vineyards, and we have seen evidence of feeding in the clusters. Leafhoppers have been difficult to find this season, and we have little evidence of powdery mildew. All seems to be quiet in the regional vineyards so far this season.
Insect and disease predictive information is available at:
http://www.enviroweather.msu.edu/home.asp
http://www.agweather.geo.msu.edu/agwx/forecasts/fcst.asp?fileid=fous46ktvc
http://www.cherries.msu.edu/
Fruit CAT Alert Reports
http://www.ipmnews.msu.edu/fruit/
This issue and past issues of the weekly FruitNet report are posted on our website at: http://www.maes.msu.edu/nwmihort/faxnet.htm
ACTUAL
AND PREDICTED DEGREE-DAY
ACCUMULATIONS
SINCE MARCH 1, 2009
Please send any comments or suggestions regarding this site
to:
Bill Klein, kleinw@msu.edu
Last Revised: 7-21-09
