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 14, 2009
GROWING DEGREE DAY ACCUMULATIONS AS OF July 13th AT THE NWMHRS
Year |
2009 |
2008 |
2007 |
2006 |
2005 |
2004 |
19yr. Avg. |
GDD42 |
1492 |
1569 |
1914 |
1846 |
1900 |
1463 |
1671.0 |
GDD50 |
853 | 937 | 1214 | 1130 | 1220 | 824 | 1023.4 |
Growth Stages at NWMHRS (7/13/09- 4:30 p.m.)
Apple: McIntosh – 36 mm fruit
Yellow Delicious – 33 mm fruit
Gala – 33 mm fruit
Red Delicious – 38 mm fruit
Pear: Bartlett: 26 mm fruit
Sweet Cherry: Hedelfingen: 23 mm fruit
Napoleon: 22 mm fruit
Gold: 21 mm fruit
Tart Cherry: 19 mm fruit
Balaton: 19 mm fruit
Apricot: 36 mm fruit
Plum: 25 mm fruit
Grapes: Late bloom
Weather Report
Daytime temperatures in the north have been seasonable, ranging from the lower 70’s to the lower 80’s. However, night-time temperatures are cool—reaching down into the 40’s. Overall, we are still behind in our degree day accumulations. For base 42, we have accumulated 1492 GDD, which is 159 GDD behind our 19-year average. Similar accumulations are evident for base 50, where we have accumulated 853 GDD, which is also behind our average by 170GDD. A thunderstorm passed through the region on Friday night into Saturday morning, and the station recorded a little under a half inch of rain.
Crop Report
Despite the cool night temperatures, crops are moving ahead. Strawberry harvest has wrapped up late last week. All fruit is sizing, and sweet cherry harvest for the stem-on market has begun. Many in the industry are attempting to harvest sweet cherries with stems attached, which means they are starting to harvest earlier than usual harvest times. At this time most brine cherries harvested with stems attached are at 20-22mm in size. Growers are applying ethephon for harvesting sweets without stems. Tart cherries are coloring, and ethephon has been applied to some earlier ripening blocks. As cherries color, trees appear to have lots of fruit. Even ripening and adequate leaf area to support the large crop are two concerns at this time.
Pest Report
Apple. We caught an average of 4 codling moth per trap this week at the Research Station. Season-long trap catch history is as follows: 1-0-2-1-7-7-0-1-4. Spotted tentiform leafminer are maintaining trap catches in the 20’s with an average of 26 per trap, as compared to 29 per trap last week. Oriental fruit moth trap catch is down from 1 per trap last week’s to 0 this week. Oblique-banded leafroller continue to emerge consistently with an average of 16 per trap. Green apple aphid populations have risen sharply at the Research Station this week, and area growers are also reporting high populations. The 0.42” of rain on July 11th caused the apple scab model to predict a light infection period in Northport. Just under 100% apple scab ascospore dispersal is predicted based on a biofix of McIntosh green tip 4/26.
Cherry. We continue to catch cherry fruit fly at the Research Station with an average of 4 per trap. We also have received reports of cherry fruit fly catch in area orchards. In addition, one black cherry fruit fly was caught at the Station this week. We are often the first location in the state to catch fruit fly, so growers should utilize their on-farm trap catch or earliest regional trap catch (excluding the Research Station) to biofix. In cherries, American plum borer emergence appears to be tapering off with season-long catch as follows: 37-6-15-7-9-1-1-1. Lesser peach tree borer continues to emerge with trap catches of 7-18-7-6-4 over the past five weeks. Greater peachtree borer continue to emerge for the fourth week in a row with an average of 4 per trap this week. Oblique-banded leafroller numbers are remaining consistent in cherry with an average of 10 per trap compared to 9 per trap last week. Plum curculio remains active. We have also seen high populations of black cherry aphid, mostly in sweet cherry but also in tarts. As sweet cherry harvest approaches, black cherry aphid management can wait until after harvest, unless heavy infestations are on young trees which can cause death. There are a variety of excellent materials for black cherry aphid that can be found in the Michigan Fruit Management Guide. The first reports of American brown rot in sweet cherry clusters began coming in last week and large oblique-banded leafroller larvae are being reported in clusters. The cherry leaf spot model predicted a low infection potential on July 11 based on the 0.42” of rain the region received. Sour cherry yellows is prevalent in many area tart blocks this season, particularly in older trees.
Grapes. We continue to catch just a few grape berry moth sporadically around Leelanau and Old Mission Peninsulas. Potato leafhopper adults and nymphs are also being sighted, although in relatively low numbers. Rose chafer continues to mate and feed in area vineyards. One area scout reported the first Japanese beetle sighting this week so growers should be looking for this pest. We have had no reports of powdery or downy mildew yet. However, as we are in the critical period to prevent powdery mildew on clusters (immediately prebloom and the three to four weeks following bloom), susceptible varieties should remain protected. For growers interested in the new grape berry moth model on enviroweather.msu.edu, based on a biofix of June 22, we have accumulated 386 DD47 towards the 801 DD47 estimated for second generation egg laying. The grape berry moth model is still being tested for accuracy in the north region and should be utilized in conjunction with careful scouting.
CHERRY FRUIT FLY IN 2009
Erin Lizotte, District IFP/IPM Educator
As many growers transition to the new pesticides that have recently become available, monitoring for cherry fruit fly (CFF) on individual farms has become very important. This season, we have observed a few farms with higher trap catches in orchards utilizing newer chemistries. The following monitoring recommendations are abridged from the work of Dr. Larry Gut, MSU Department of Entomology: “The date of first emergence, as well as subsequent activity of CFF can be monitored using yellow sticky traps baited with ammonium acetate. Place traps adjacent to border areas with known alternate hosts of CFF such as wild black cherry. Hang traps two weeks after shuck split when fruit begins to take on a yellowish color. The greater the number of traps deployed per acre (at least one trap per 2.5 acres), the greater the confidence level in basing treatment decisions on fly catch. To differentiate between flies utilize the wing pattern guide provided. Use on-farm fly catches along with regional trapping information to determine control treatment timing. Because of 0% tolerance for CFF in harvested fruit, a conservative approach is recommended. Applications of OPs and other contact insecticides are timed for fruit fly egg laying, which occurs 7-10 days after the first fly is captured. If a fly is trapped on-farm and a regional trap catch is recorded prior to the on-farm fruit fly capture, the treatment should be applied 7-10 days after the earliest capture. However, basing treatment decisions solely on regional information may lead to unnecessary insecticide applications. If you are using a newer insecticide chemistry that requires ingestion of the material for effective control, the insecticide should be applied immediately after the first fly has been captured in a trap.”
BLACK CHERRY APHID
Erin Lizotte, NWMHRS
20TH ANNUAL VITICULTURE DAY AT SOUTHWEST MICHIGAN RESEARCH AND EXTENSION CENTER
Michigan State University (MSU) Extension and the National Grape Cooperative are teaming up this summer to host the 20th Annual Viticulture Day July 29 from 10 a.m. to 7 p.m. at the Southwest Michigan Research and Extension Center in Benton Harbor.
The conference includes a trade show and 10 workshops focusing on insect and disease management and other horticultural issues specific to grape production. Presenters include members of the MSU Grape Team and other viticulture experts. The day will conclude with wine hospitality and a steak cookout.
“The viticulture field day is a favorite among growers in the state,” said Doug Buhler, Michigan Agricultural Experiment Station (MAES) associate director. “The information presented is designed for growers, consultants, field scouts, company representatives and others that need current in-depth, practical information about viticulture and pest management.”
Early bird registration for the field day is $20 if registered before July 17 or $25 after early bird registration. Registration includes all workshops, trade show, lunch and steak cookout. Registration forms can be downloaded from http://tinyurl.com/pc4xgf. For more information, contact the Southwest Michigan Research and Extension Center at (269) 944-1477.
The mission of the Southwest Michigan Research and Extension Center is to enhance the economic viability of agriculture in Michigan through the development and practical demonstration of technological advances in plant materials and cultural practices, as well as sound farm management.
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: 7-14-09