So how delayed are we? The DD accumulations calculated from March 1-May 15 for the past 6 years for Tomah, WI (41/85°F thresholds, single sine method, horizontal cutoff) are:

2008 – 369
2009 – 463
2010 – 607
2011 – 354
2012 – 832 (wow!)
2013 – 336

It seems that slowly, but surely, spring is arriving.

If you are interested in calculating your own DD accumulations, the University of California-IPM has an excellent DD calculator available on their website. Scroll down to the bottom of the page, enter your upper and lower thresholds (the default calculation methods are fine for the rough estimate) and click on calculate. You can then either enter your weather data online or upload a file.

Annie

The College of Agricultural and Life Sciences, at University of Wisconsin-Madison, publishes Grow Magazine three times a year, highlighting agricultural research in Wisconsin. The University offers a free subscription, go here for the subscription form. For a pdf copy of the latest Grow issue, Spring 2013, go here.

– Liz Bosak

Missed a workshop? The WDATCP has a webinar archive with free videos hosted by YouTube.

–Liz Bosak

To learn more about her work on native pollinators, see this article.

Other research highlights from the University of Wisconsin and UW-Extension include presentations by Rebecca Harbut, Jed Colquhoun, Jack Perry, Lisa Wasko-De Vetter, Christelle Guedot, Eric Zeldin, and Patty McManus.

The Pesticide Applicator Training will take place from 8:00 AM until 11:45 AM on Tuesday, January 22.

Davey Hyer and Jane Larson from the Wisconsin Department of Agriculture, Trade, and Consumer Protection with be talking about “Cranberry Farm Inspections: Strengths and Areas for Improvement.” Bill Outhouse and Walt Coussens will be discussing the use of food grade oils and grease for harvest equipment lubrication. Have truck maintenance issues? Well, Harry Newmann will be there to answer your questions. Many more subjects will be covered including safe working conditions, oil spill prevention and containment, animal damage, harvest technologies, irrigation water pH, and personal protective equipment.

Many researchers from the USDA-Agricultural Research Service, University of Wisconsin, and University of Wisconsin-Extension will be presenting at this year’s Cranberry School:

–Spotted Wing Drosophila, Sparganothis Phenology, and a new look at the flooding data, Shawn Steffan, USDA-ARS

–Carrying-on some tasty bits of the UW Cranberry Breeding Program, Eric Zeldin, UW Horticulture

–Genetics Program Update, Juan Zalapa, USDA-ARS

–Sustainability Survey, Jed Colquhoun, UW Extension

–Irrigation and Soil Moisture Monitoring, Rebecca Harbut, UW Extension

–What’s New in the Pesticide Screening Program, Jack Perry, UW Pesticide Screening Program

–Reflecting on Bud Appearance and its Role in Yield Prediction, Lisa Wasko-DeVetter, UW Horticulture Grad Student

–Pheromone Mating Disruption, Annie Deutsch, UW Entomology Grad Student

–Meet Our New Entomologist, Christelle Guedot, UW Extension

–Disease Observations from 2012, Patty McManus, UW Extension

–Targeting Red-Headed Flea Beetle Larvae, Liz Bosak, USDA-ARS

Any farm that produces more than $1,000 is eligible to participate. The information will remain confidential.

The homepage has links to the results of the 2002 and 2007 Census.

Cranberries and spotted wing Drosophila (SWD) in Wisconsin

Shawn Steffan (USDA-ARS Madison, WI), Jana Lee (USDA-ARS Corvallis, OR), Laura Lavine (Washington State University), Doug Walsh (Washington State University), Chase Metzger (Washington State University), Juan Zalapa (USDA-ARS Madison, WI), Christelle Guédot (University of Wisconsin-Madison), and Phil Pellitteri (University of Wisconsin-Madison).

This holiday season, there will be one demographic that won’t want to eat fresh cranberries: spotted wing Drosophila maggots. Drosophila suzukii, commonly known as SWD, does not appear to like cranberries very much. Following multiple replicated trials using ripe, under-ripe, and over-ripe organic Wisconsin cranberries, SWD females would not (or could not) insert eggs into under-ripe or ripe cranberries. This suggests that healthy, current-year fruit should be safe from attack.

Scaptomyza (Drosophilid)

Among the over-ripe, decaying cranberries (harvested, frozen, thawed, refrigerated) just two eggs were found among many berries, but no mature larvae were detected, and no adults emerged. Fortunately, rotting fruit don’t make it into the harvest because they generally don’t float. Decaying fruit get devoured every spring and summer by other drosophilid flies (see photograph above), various beetles, and countless hordes of mites and springtails.

While none of the SWD larvae successfully developed within the highly acidic flesh of fresh cranberries, studies using physically damaged cranberries showed that SWD could develop to adulthood. Again, these berries represented wounded, decaying fruit, not the sort of berries that would get harvested. That said, SWD populations could build within cranberry beds and potentially play a role in regional source-sink dynamics.

Unfortunately, SWD females love blueberries and raspberries—this we learned early. The good news for cranberry growers is that SWD adults have only rarely been trapped in/near cranberry beds, and in these cases, a blueberry or raspberry patch was nearby.

So, the take-home message: current-year cranberries (that aren’t damaged and/or rotting) appear to be safe from SWD attack. Conversely, last-year’s decaying bounty of unharvested cranberries may be vulnerable. SWD populations will likely be found each spring and summer in fruit-growing regions, but the risk to cranberry production seems minimal.

If you are suspicious of any infested fruit, contact your local Extension agent.

For other fruit crops, here is a list of resources that may be helpful:

University of Wisconsin Extension has released an article on Spotted Wing Drosophila, Drosophila suzukii, with several suggestions for scouting and trapping the fruit flies.

University of Wisconsin-Madison has a website about the Spotted Wing Drosophila in Wisconsin.

The University of Minnesota and Michigan State University have web pages with extensive lists of resources including a map of counties with SWD in Minnesota and Wisconsin.

North Carolina State University’s Small Fruit and Specialty Crop IPM blog

Pacific Northwest Insect Management Handbook SWD page

–Liz Bosak

Wisconsin cranberry growers have avoided many negative effects of the drought but the same is not true for growers in Washington. Reduced water resources may delay or prolong the harvest. For the full Seattle Times article, go here.

–Liz Bosak