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What's Hoppening: Musings from the Hopyard!

It’s a Wet One!

Posted: June 7th, 2017 by hoppenin

All spikes indicate a day or days when there is high risk for downy mildew. Click on image to enlarge.

Well, 2016 was a droughty growing season, but so far 2017 is shaping up to be quite the opposite. This damp weather can be a problem for a few reasons but especially because it creates a haven for downy mildew infection which can greatly reduce harvest yield. Since mid-April, we have forecasted that 45% of days between April 15 and June 6 have had a high risk for disease incidence. Plants are very vulnerable to downy mildew infection during periods with prolonged moisture on the shoots and foliage. For more information on downy mildew, please be sure to check out our earlier blog posts about downy mildew.

Similar to the 2015 season, the cool, damp weather has set the hops back in their vegetative growth.  June is a very important month for physiological hop development. By the time the plants reach the top of the trellis, the number of cone-producing side shoots will be determined. Hops are a photoperiod sensitive crop, so if plants are unable to reach the top of the trellis by the time the day length changes (generally on summer solstice, June 21) and begin their reproductive phase, they will not produce as many cones.

Keep your fingers crossed for drier weather! And remember to keep calm and hop on.

Beware of Bull Shoots!

Posted: May 30th, 2017 by hoppenin

Bull shoots emerging from a hop hill. Click on image to enlarge.

Due to the cold, wet weather this spring, our hops have been a little slow to emerge from the ground, but they’re finally ready to train!

If you’ve been looking at your hopyard and thinking the same thing, be cautious of bull bines.

These bines are the first shoots to emerge from the ground in the spring, and while they look tall, vigorous, and inviting, avoid training these shoots!

Bull bines produce fewer side arms than regular shoots and can yield 400-600 pounds fewer dry hops than the later emerging shoots. Bull bines can be identified by their physical characteristics — they are hollow, stiff, and brittle. Since they grow so quickly, they have long intermodal spaces too.

Regular shoot (left) as compared to a bull shoot (right). Click on image to enlarge.

Their color is another way to identify them — they tend to be purple. In comparison, regular shoots are flexible, more green in color, and less hollow; these shoots also have a shorter internodal space than the bull shoots.  These shoots are slower to emerge, but the difference in cone yield is worth the wait!

We recommend removing the bull shoots from the hills, so the plant can allocate more nutrients and energy to growing the more productive secondary shoots.

Happy training and remember to keep calm and hop on…




Got Downy Mildew?

Posted: May 28th, 2017 by hoppenin

As you know from previous What’s Hoppening posts, the first signs that a plant is infected with downy mildew will be basal spikes. But these are not the only symptoms of downy mildew.

Downy mildew on aerial spike. Click on image to enlarge.

As the season progresses, aerial spikes and infected leaves will begin to appear. Like basal spikes, aerial spikes are indicative of systemic plant infection. Aerial spikes have similar features to basal spikes, except they’re found on your trained plant rather than on the ground! Both side arms and the main bine may become aerial spikes if they are infected with downy mildew. Aerial spikes have the same chlorotic appearance and short internodes as basal spikes. If an aerial spike is a trained bine, it will stop growing and fall off its string. It is important to remove these infected bines and train only healthy shoots to produce the highest yielding crop and keep downy mildew from spreading to uninfected plant material.

Infected leaf with downy mildew lesions. Click on image to enlarge.

Leaves may also be infected with downy mildew and are an indication of in-season infection. When downy mildew infects a leaf, it creates necrotic lesions, delineated by leaf veins. These lesions are angular and have very distinct edges, which can help with disease identification. Leaf lesions may also be covered in spores after wet periods, so be careful handling these leaves to reduce the risk of spreading infection.

Downy mildew can be a tough pathogen to fight, but there are options. Increasing air flow is a simple and straightforward cultural control. By maximizing the breeze in your hopyard, you can reduce the amount of time your foliage spends wet; this decreases the time that downy mildew is producing spores. Stripping the lower 2 to 4 feet of foliage once a plant is trained and established can reduce moisture, as well as keeping weed biomass low and driverows mowed.

During the season, fungicides are your friend. In wet weather, you should be prepared and ready to spray biofungicides during the day prior to an expected rain event. There are a variety of conventional and organic fungicides registered for hop use. If you live in Vermont, a list of OMRI-approved biofungicides can be found in the 2016 Hop Biofungicide Trial Research Report.  It is very important to only apply fungicides that are listed in your state for use on hops so be sure to check the label.

For more information on downy mildew in hops, check out a recording of our webinar with plant pathologist David Gent and/or visit the resources on our website. Until next time, keep calm and hop on.

April Showers Bring May…Downy Mildew

Posted: May 22nd, 2017 by hoppenin

Basal spike infected with downy mildew. Click on image to enlarge.

Although the rain is a welcome change from last year, all this moisture indicates that it is prime downy mildew season! Since April 15, we have had 8 days with a high likelihood for infection at the hopyard at Borderview Research Farm in Alburgh, VT, compared to only 2 at this point last year.

Downy mildew is the most persistent hop pathogen in the Northeast and can be difficult to control. Downy mildew sporulates in warm, moist conditions, and can spread very quickly. Plants are most at risk during rainy days because the plant’s stomata, or pores, are open during the day, leaving an open pathway for disease invasion. If there is excess moisture on a hop plant and spores are present, leaves may become infected in as little as 1.5 hours in warm conditions! Shoots may become infected if moisture persists for 3 hours.

Chlorotic basal spike with leaf desiccation. Click on image to enlarge.

Downy mildew is a systemic infection–once your plant has downy mildew, it is infected for life. After the growing season, downy mildew overwinters in the crown of an infected plant. The first sign of infection in spring is the presence of basal spikes. Basal spikes are chlorotic, or yellowing, and have shortened internodes, or the space between leaf pairs. A severely infected basal spike may also have desiccated leaves. It is important to remove all infected spikes and train only health plants. By leaving infected material in your hop yard, you risk infecting healthy plant material.

Basal spikes may be removed using sanitized equipment (clippers or scissors), but sanitization is key!  If you’re not taking proper precautions, you run the risk of spreading fungal spores to healthy plants yourself! Basal spikes may also be removed through crowning, a process that mechanically removes the first growth of the season as well the top of the crown.  This serves the dual purpose of removing inoculum as well as removing plant material that can be infected.

To help you with scouting downy mildew on basal spikes, we have created a sheet you may use to tracking and documenting downy mildew in your yard: http://www.uvm.edu/extension/cropsoil/wp-content/uploads/Downy_Mildew_Scouting_Basal_Spikes.pdf. For more information, visit our website and/or check out the article, Managing Downy Mildew.

And remember, stay calm and hop on.


Recruiting NE Hop Growers for Pest and Nutrient Management Project

Posted: April 17th, 2017 by hoppenin

Our University of Vermont Extension Northwest Crops & Soils (NWCS) Team is currently recruiting Northeast hop growers for a 3-year NE-SARE project looking to advance pest and nutrient management strategies for Northeast hop production.

As a participant, you will have access to the following opportunities.

  • Complete an introductory survey that allows us to collect basic information about you and your hopyard, your understanding of hopyard management and your project learning goals.
  • Participate in our goScout program. By responding to a handful of short hopyard fertility and pest management questions every other week, we will compile responses to help us all learn more about pest pressure and management options throughout the region during the season.
  • Learn and share pest & nutrient management information through our Hops Power Hour webinars, offered monthly every fourth Monday on the month at noon from April 24 to September 25, 2017. Dr. David Gent, USDA ARS Research Plant Pathologist and author of Field Guide for Integrated Pest Management in Hops, will kick off the series on April 24 to discuss downy mildew management and additional pertinent issues in the early season hoypard.

If you are interested in participating in this project, please click here to complete the introductory survey, but act fast because space in this project is limited and offered on a first-come, first-served basis. If you have any questions about the project, please email Scott Lewins (slewins@uvm.edu).

As we start this new growing season, remember: keep calm and hop on!

Six-Year Study Shows Hop Insect Patterns

Posted: March 17th, 2017 by hoppenin

Excited for the 2017 growing season? We are…and so are the bugs!

We recently published our final Organic Hop Variety Trial Report that includes 6 years of data on disease, weed, and insect pest populations found in our hopyard, as well as yield and quality performance of more than 20 hop varieties we evaluated.

Our research showed seasonal patterns of the three major arthropod pests of hops found in the Northeast:

  • Two-Spotted Spider Mites (TSSM),
  • Potato Leafhoppers (PLH), and
  • Hop Aphids (HA). 

Mean number of Two-Spotted Spider Mites (TSSM), Potato Leafhoppers (LF), and Hop Aphids (HA) found per leaf by year, 2011-2016, Alburgh, VT. Click on image to enlarge.

We also looked at beneficial insects, including the Spider-Mite Destroyer and its habits.

We found that that the incidence of each pest varies widely by year, based on weather conditions. For example, TSSM populations responded to the warm and dry conditions we experienced in 2012 and 2016, while HA populations tended to favor cool and moist conditions.

PLH seemed to get a big boost out of a warm winter. Because they migrate from the south each season, warmer winters allow PLH to over-winter further north, shortening their journey to Vermont in the spring and early summer.

Average number of Hop Aphids (HA), Potato Leafhoppers (PL), Spider-Mite Destroyers (SMD), and Two-Spotted Spider Mites found per leaf by date, 2011-2016, Alburgh, VT. Click on image to enlarge.

Our research also tracked pest levels throughout each growing season. While overall pest numbers varied greatly from year to year, the populations for each pest usually peaked at the same time of the year. PLH tended to peak in late June, TSSM in the hot and dry periods of late July and early August, and HA populations peaked right around harvest through September. Not surprisingly, the population of Spider-Mite Destroyers (SMD), beneficial arthropods that prey on TSSM, followed TSSM population levels.

Through our study, we found that some hop varieties seem more susceptible to certain hop insect pests. For example, Liberty, Perle, Teamaker, and Crystal seemed particularly sucseptible to TSSM. We observed that Mt. Hood, Liberty, Saaz, Newport, and Santiam were most susceptible to PLH damage. Conversely, Centennial was consistently among the most resistant to TSSM and PLH.

Further research results on pests and variety performance as well as valuable lessons we looked over the past six years in our hopyard can be found in our Organic Hop Variety Trial Final Report at: http://www.uvm.edu/extension/cropsoil/wp-content/uploads/2016-Hop-Variety-Trial.pdf.



Mark Your Calendar: 8th Annual Hop Conference, February 25, 2017

Posted: February 7th, 2017 by hoppenin

We invite you to join us for our 8th Annual Hop Conference scheduled for Saturday, February 25, 2017.  It will be held at the Sheraton Burlington Hotel in Burlington, VT, 9:00 a.m. to 4:30 p.m.

View our Conference flyer for details.

This year’s conference will include both advanced and beginning sessions as well as hearing from the following presenters during the morning session:  Jaki Brophy of Hop Growers of America, hop crop consultant Julien Venne, brewer Bobby Grim of Foam Brewers, and David Gent of USDA-ARS.

Advanced sessions will include presentations on characteristics of a beer brewed with local hops with Rich Michaels of Saranac Brewery, wild hops and downy mildew resistance with Josh Havill of UMN, pelletizing hops by Tim Kostelecky of John I. Haas, and UVM research updates.

Beginning hop grower sessions including information on hop cost of production, starting a commercial hop yard, constructing a hop yard, hop irrigation, basic hop agronomy and IPM, and harvest and post-harvest processing.

Go to https://www.regonline.com/hopconference to register today!

Speaker panel from 2016 Vermont Hop Conference.

The registration fee, which includes lunch, is $75 per participant and $65 for NeHA members.  There is also an option to view the conference as a live broadcast for $35.  The Hops Live Broadcast will include the morning session and the advanced sessions during the afternoon.  We are sorry that we cannot cover both the advanced and beginning sessions which are being held simultaneously.

On-site check-in at the event opens at 8:15 a.m. and the conference starts promptly at 9:00 a.m.  Please contact Susan Brouillette if you have questions.

Hope to see you there!

Ready for Hop Harvest?

Posted: August 9th, 2016 by hoppenin

It’s almost harvest time, folks! With such a hot, dry year, be prepared for some varieties to be ready earlier than usual. Remember to check the labels on any pesticides you are using to allow the appropriate window between the last pesticide application and harvest.

Have you seen our fact sheet on determining when hops are ready for harvest? Check it out here: http://www.uvm.edu/extension/cropsoil/wp-content/uploads/Hop-Harvest-Determination-factsheet.pdf.

Also, we have a handy calculator for dry matter/moisture content math: http://www.uvm.edu/extension/agriculture/engineering/?Page=hopscalc.html.

Hop harvest timing from 2012 to 2015 at Borderview Farm, Alburgh, Vermont.

Hop harvest timing from 2012 to 2015 at Borderview Farm, Alburgh, Vermont. Click on image to enlarge.

In addition, we put together a chart of harvest dates in our hopyard over the past four years. If you’re located in the Northeast, this might help you ballpark your harvest window.

Note that we use two opposite terms at hop harvest time–dry matter and moisture content. We harvest at a dry matter of 22 to 27% (that’s 73 to 78% moisture). Then, when we dry hops after harvest, we dry them to a moisture content of 8 to 10% (that’s 90 to 92% dry matter). This interchange of terms might seem confusing but that’s just what is used throughout the industry. One more note on dry matter: Since dry matter is the opposite of moisture content, dry matter will increase as hops mature in the field. So if you measure your hops at 18% dry matter, they’re not ready yet!

Good luck with harvest and remember to keep calm and hop on!

See Hops at Upcoming Annual Field Day, July 28

Posted: July 21st, 2016 by hoppenin

Bird's eye view of our hopyard.

Bird’s eye view of our hopyard.

WHAT:  UVM Extension Northwest Crops and Soils Field Day

WHEN:  Thursday, July 28, 2016

TIME: 10 am to 3:30 pm

WHERE: Borderview Farm, 146 Line Road, Alburgh, VT

If you haven’t had a chance to sign up for our Annual Crops & Soils Field Day, register today, as it is just around the corner.  Our theme this year is “Eat It, Drink It, Feed It, Fuel It – Conducting Food System Research Crop by Crop” and we will be featuring the end-products made from the crops we’ve been researching at a ‘Tasting Tent.’

We will be touring the hopyard along with other research trials we are conducting. Hops specific presentations will include:

  • Small-scale harvesters by hopsharvester.com
  • Fertility in our hopyard
  • Pest scouting and identification
  • On-going research trials on Biofungicides and crowning
  • Q and A with the team
Folks tour the hopyard at past annual field day.

Folks tour the hopyard at past annual field day.

Highlights of the day will also include:

  • Tour of research trials
  • New research crops including industrial hemp and milkweed
  • Tasting Tent – several Vermont businesses with locally grown products
  • Innovative equipment
  • Organic weed control strategies
  • BBQ chicken lunch
  • And much, much more!

Register today!! Cost is $25 per person (non-farmer) and $10 per farmer.  Includes lunch and CCA credits.

See you at the Field Day! And until then, keep calm and hop on…

Summertime and the Living is Easy…Especially if You’re a Two Spotted Spider Mite

Posted: July 13th, 2016 by hoppenin

Adult female two spotted spider mite with prominent black spots on each side (photo courtesy of D.G. James).

Adult female two spotted spider mite with prominent black spots on each side (photo courtesy of D.G. James).

As we are approaching the hottest time of year, with temperatures projected for the 90’s midweek, it is a great time to remind you to be on the lookout for two spotted spider mites. These tiny cousins of spiders also produce webbing, though spider mites use it to protect themselves (from the elements, natural enemies or pesticides), not to catch prey. Spider mite damage occurs when they jam their mouthparts into, and then sucking the life out of, your hops.

Stippling caused by  two spotted spider mite damage.

Stippling caused by two spotted spider mite damage.

At this point of the season, spider mite feeding causes a characteristic stippling of leaves which, at low to moderate levels, doesn’t cause economic injury since there is no apparent effect on yield or quality later in the season. Heavy infestation of two spotted spider mites can lead to reduced photosynthesis or even defoliation. This has led to the economic thresholds in the Pacific Northwest ranging from an average of 5-10 mites per leaf in mid to late July. In other parts of the world, thresholds of up to 60 mites per leaf are used.

Two spotted spider mites on the underside of a hop leaf.

Two spotted spider mites on the underside of a hop leaf.

Hot, dry, dusty conditions, those typical of August, tend to favor rapid two spotted spider mite population growth. Unfortunately, August is also when hop cones are maturing. If spider mites make their way into cones there can be a decrease in quality, and severe spider mite infestations can cause hop cones to become brittle and shatter. So monitoring two spotted spider mites from now until harvest is crucial to ensure mite infestations don’t get out of control.

It is important to recognize that pesticide applications, particularly broad-spectrum insecticides and repeated application of sulfur, can actually exacerbate the problem. Following an insecticide application, spider mite populations are generally quick to rebound, much quicker than natural enemies like spider mite destroyers. This allows spider mites to reinfest your yard without any natural control. Whereas using selective miticides can enhance biological control.

For additional information on two spotted spider mites and much, much more, check out the newly updated Field Guide for Integrated Pest Management in Hops. And of course, keep calm and hop on…

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