January Thaw (again)

It's "January thaw" time in North Carolina, the current temperature is 67F (19.4C). So growers and researchers are worried. Will blackberry buds be breaking?

For those of you that were in Savannah last week, both John Clark and I discussed chilling models. John described the Utah Model ( models 5 and 6 below are variations of the Utah model), that assigned partial ceiling units and subtracted units. I discussed a simpler model (model 2) that just accumulated chill units when the temperature was between 32-45 F and the starting date occurred when temperatures were below 28F.  See the tables at the end of this post for all the details.

Based on the data collected so far this winter by the State Climate Office of North Carolina, we have somewhere between 259-420 chilling hours in Raleigh. We usually get around 800 units, because we are well below 800, buds should remain dormant. However, in the western part of the state, chilling units are higher and a lengthy warm spell may stimulate some buds.

Here are some chill units that have accumulated so far around the state.

Location (CRONOS)	Blueberry model	Blackberry model 1	Blackberry model 2	Blackberry model 5	Blackberry model 6
Raleigh (LAKE)	832	406	259	420	375
Salisbury (SALI)	978	788	517	727	612
Lincolnton (KIPJ)	953	692	433	631	537
Hendersonville (BEAR)	NA	923	512	782	627
Castle Hayne (CAST)		315	195	212	171

You can calculate your chilling units near you at this site State Climate Office of North Carolina Model 2  (it also can calculate for stations in  GA, KY, MD, NC, SC, TN , VA, WV).

If you would like me to look up chilling units for other models for your area, send me an email. Gina_Fernandez@ncsu.edu.

http://climate.ncsu.edu/cronos/blackberry

Details of all the chilling models.

NCSU Blueberry Model

Temperature	Units of chilling
< 45°F (7.2 °C)	1
45-55°F (7.2-12.8 °C)	0.5
55-65°F (12.8-18.3 °C)	-0.25
>65°F (18.3 °C)	-1.0

The model begins when it has a positive balance that is not negated by warmer weather. Once 800+ chill hours have accumulated, points are no longer negated for temperatures 55° and above. The model ends February 28 at midnight. 

Blackberry model 1

Temperature	Units of chilling
<44.6°F (7.2°C)	1

Starts when hit 28°F for the first time in the fall.

Blackberry model 2

Temperature	Units of chilling
32-44.6°F (0-7°C)	1

Starts when hit 28°F for the first time in the fall.

Blackberry model 5

Temperature	Units of chilling
32-48.38°F (0-9.1°C)	1
48.5-54.3°F (9.2-12.4 °C)	0.5
54.5-60.6°F (12.5-15.9°C)	0
60.8-64.4°F (16-18°C)	-1

Starts when hit 28°F for the first time in the fall.

Blackberry model 6

Temperature	Units of chilling
34.7-36.3°F (1.5-2.4°C)	.5
36-48°F (2.5-9.1°C)	1.0
48.5-54.3°F (9.2-12.4°C)	.5
54.5-60.6°F (12.5-15.9°C)	0
60.8-64.4°F (16-18°C)	-.5
>66°F >18°C)	-1

Starts when hit 28°F for the first time in the fall.

Utah Chill model

Temperature	Units of chilling
<34.5°F (1.4°C)	0
34.6-36.4°F (1.5 – 2.4°C)	.5
36.5-48.4°F (2.5- 9.1°C)	1.0
48.5-54.4°F (9.2-12.4°C)	0.5
54.5-60.6°F (12.5-15.9°C)	0
60.8-64.4°F (16-18°C)	-.5
>64.5°F (18°C)	-1.0

National Strawberry Survey

Strawberry growers, please take some time to fill out this survey. It will help a large group of strawberry researchers and extension personnel develop a grant.

Fore a bit more detail:

North American Bramble Growers RFP

Caneberry Researchers:

It is an exciting time in the caneberry world as production continues to grow. With the growth, there is an increasing need for research to optimize the growth of this demanding crop. Do you need some $ to get a project started? Here is your opportunity for some seed money...

The RFP for the 2017 North American Raspberry and Blackberry Association is out, see the link below. The deadline for this years proposal is Dec 21, 2017 (one more thing to add to your list of year end proposals and reports). Please pass this on to others at your institutions that may be interested (entomologists, pathologists, weedologists, post harvest, food scienctists, economists). I have tried to include some of their names in the email above, but it is not complete, especially if you are not on the south/east coast. 

http://www.raspberryblackberry.com/supporting-research-a-request-for-proposals/

Note, although the NARBA meeting is taking place next week, the NABG RF (the research arm of NARBA) is not meeting until Jan in Savannah. Contact me if you have any questions. 

Fall Caneberry Chores 2016

Blackberry and Raspberry Seasonal Checklist Fall 2016

Gina Fernandez, Small Fruit Specialist, North Carolina State University

Many of us are recovering from the wrath of Hurricane Matthew. I posted some information on the Team Rubus Blog prior to the storm.  In parts of eastern NC, soils are saturated and there is still a threat of additional flooding as the rivers continue to fill with water from the tributaries. There is some information in the blog post on how to dealing with flooded berry fields. http://teamrubus.blogspot.com/2016/10/hurricane-matthew-preparation-for.html

The NC State University Extension has a new look to their portals. Check out the Blackberry and Raspberry Portal here. https://rubus.ces.ncsu.edu

The Northwest Berry Foundation has a great newsletter that focuses on production issues in the Pacific Northwest. However, they pull information from a range of sources, and many of the articles are relevant for all berry growers. It comes out on a weekly basis during the production season and less often during the off-season. Here is a link to the most current newsletter. therea are a couple of articles on labor situations on the west coast. http://www.nwberryfoundation.org/sfu.html

FALL

Plant growth and development

ü  Primocanes continue to grow but growth rate is slower

ü  Flower buds start to form in leaf axils on summer-fruiting types

ü  Carbohydrates and nutrients in canes begin to move into the roots

ü  Primocane fruiting types begin to flower in late summer/early fall and fruit matures until frost in fall

ü  Primocane leaves senesce late fall

Harvest

ü  Primocane-fruiting raspberry harvest

ü  Primocane-fruiting blackberry harvest

Pruning, trellising and tunnels

ü  Spent floricanes should be removed as soon as possible

ü  Optimal time to prune is after the coldest part of the season is over. However pruning can start in late fall if plantings are large (late winter for smaller plantings).

ü  Start trellis repairs after plants have defoliated

ü  Remove covers on three-season tunnels

Weed management

ü  Many summer weed problems can be best managed in the fall and winter using preemergent herbicides. Determine what weeds have been or could be a problem in your area. Check with your states agricultural chemical manual and local extension agent for the best-labeled chemicals to control these weeds

Insect and disease scouting

ü  Continue scouting for insects and diseases

ü  Remove damaged canes as soon as possible to lessen the impact of the pest

ü  Check the Southern Regional Bramble integrated Management Guide for recommendations http://www.smallfruits.org

Planting

ü  Growers in warmer areas (e.g. extreme southeastern NC) can plant into early December.  Preparations for winter planting should have already been made. If you have questions about winter planting please contact your local county extension agent

ü  In cooler areas, prepare list of ­cultivars for next spring’s new plantings. Find a commercial small fruit nursery list at http://www.fruit.cornell.edu/berry/nurseries/

Fertilizer

ü  Take soil tests to determine fertility needs for spring plantings.

ü  Non-nitrogenous fertilizers are best applied in the fall to established plantings.

ü  If soil is bare, plant an overwintering cover crop (e.g. rye) to build organic matter and slow soil erosion.

Marketing and miscellaneous

ü  Order containers for next season

ü  Make contacts for selling fruit next season

Make plans to attend Grower meetings! Blackberries and raspberries are part or all of these programs.

• North American Berry Conference, Grand Rapids MI
• December 4-6, 2016.  Because the Great Lakes Expo is held in December, we actually have TWO conferences in one calendar year — this December meeting will replace our Winter 2017 conference, which would typically be held in January or February.
• This year NARBA is meeting jointly with the North American Strawberry Association (NADSGA), in association with the Great Lakes Fruit, Vegetable, and Farm Market Expo in Grand Rapids, Michigan.
• This is a highly regarded regional meeting that attracts more than 4000 participants and 450 exhibitors. It is one of the largest trade shows for fruit and vegetable growers, greenhouse growers and farm marketers in North America!
• http://www.raspberryblackberry.com/2016-north-american-berry-conference/
• Southeast Regional Conference and Tradeshow, Savannah, GA
• Sessions on blackberry and strawberery, blueberry, muscadines and more!
• January 5-8, 2017, at the Savannah International Trade and Convention Center
• Registration and program information can be found at
• http://www.seregionalconference.com
• Video of past conference
• https://vimeo.com/174265440

Key Resources:

Southern Region Integrated Bramble Management Guide:

http://www.smallfruits.org/SmallFruitsRegGuide/Guides/2016/2016BrambleSprayGuide.pdf

Southeast Regional Bramble Production Guide: http://www.smallfruits.org/SmallFruitsRegGuide/index.htm

Blackberry and Raspberry Grower Information Portal:

http://rubus.ces.ncsu.edu

Social Media links:

Twitter: @NCTeamRubus  

Facebook : Team Rubus   

Blogs: http://teamrubus.blogspot.com/

Hurricane Matthew Preparation for Caneberries

The latest forecasts have Hurricane Matthew just skidding the southeastern coast of NC. Caneberry Growers in Eastern NC (and the rest of the southeastern US) should be preparing their fields now and be prepared after the rains leave.

Here are some things that can be done before the storm:

IF YOU ARE IN AN AREA WITH HIGH PREDICTED WINDS: You should consult with your tunnel manufacturer to determine how much wind your tunnels can withstand. Removing or skinning the plastic off the tunnels  is a whole lot less costly than having the entire tunnel mangled.

IF YOU HAVE A SHIFT OR ROTATING ARM TRELLIS: Lay the trellis in the horizontal or down position and make sure it can stay in that position. Some trellises do not have the capability to lock in the horizontal position. If that is the case, it may be better in the upright position.

POTENTIAL FOR ELEVATED DISEASES: Canes if properly trellised should not lodge as a result of the wind and rain. However, there may be some physical damage to canes. Make sure you walk your fields before and after the storm. There may be a need to do some extra pruning and use of a fungicide if you can get out into the field after the storm. Phil Brannen, UGA plant pathologist recommends a spray for Cane blight, before the storm. See the SRSFC for recommended chemicals. http://www.smallfruits.org/smallfruitsregguide/Guides/2016/2016BrambleSprayGuide.pdf

After the hurricane passes there may be some soils that have flooded. Here is some information from a previous post from Cornell University. Since most of the berry crops have already been harvested, we are primarily concerned with flooded fields effects on roots.

This is an excerpt form an article is provided courtesy of Cornell University. It was written for flooding situations in the northeast in the late summer. However,  a flooded field poses similar problems for plant survival and is still an issue in the fall, as plants are not yet dormant. 

DEALING WITH FLOODED BERRY FIELDS

Steve Reiners and Marvin Pritts

Dept. of Horticulture

Cornell University

PLANT SURVIVAL UNDER WATER

How long a crop can live once it is flooded and what may be the effect on yield? Berry crops can tolerate a great deal of flooding when they are dormant, but when actively growing in summer, flooding for any length of time can be detrimental. This time of year is particularly bad because plants are preparing to make flower buds for next year, and stress can compromise this process. If plant roots were under water for more than 48 hours, expect next year’s crop to be compromised as well.

Plants previously flooded may develop an off-green or yellowish color.  These plants are suffering from a complex of nutrient deficiencies, nitrogen, phosphorus, potassium and perhaps others, even though the soil contains adequate amounts. But the main deficient element is oxygen. Plant roots need oxygen to take up nutrients and water to utilize the photosynthate from the tops and to grow. With the heavy rains we have had, soils are saturated; that is, nearly all of the pore space is filled with water, leaving little room for air. Ideally, for good root growth 50 percent of the pore space should be filled with air. As soils drain, air is drawn into the soil, but when it rains, the water forces the air out of the pores. As is obvious to all, what is needed now is several rain-free days so the soils can drain and draw in air to stimulate root growth and help disperse toxic compounds that accumulate when plants lack oxygen.  Once the plant roots get adequate oxygen they will begin to grow and take up the nutrients present in the soil. Anything that can be done to remove surface water will be helpful.

Many plant diseases will be much worse following flooding rains (e.g. Phytophthora and Botrytis), so closely monitor crops and manage these diseases. Phytophthora spores are spread under flooded conditions, so chemical treatment may be warranted in susceptible crops (red raspberries and blackberries).

(Thanks to Steve Rieners and Marvin Pritts at Cornell University for sharing this with us.) 

Cane blight at end of season?

Cane blight infection at tip of cane where it had been pruned as a primocane.

Cane bight symptoms in entire canes.  Dead canes are silvery/gray in appearance. Photo phil Brannen. UGA

As the blackberry season winds down, there are several reports of loss of crop and cane death before the crop ripens. This is often occurring in plantings that are low or no spray such as homeowners and small commercial plantings. The canes become infected when they are primocanes as tipping or pruning occurs in the summer. 

In at least one instance, samples sent into the NCSU Plant Insect and Disease Clinic have confirmed that Cane Blight caused by the fungus, Leptosphaeria coniothyrium. This disease is common in roses and some ornamentals. 

Here is a link to the disease. http://extension.uga.edu/publications/detail.cfm?number=C894

Here is a link to the IPM manual that has control methods: http://www.smallfruits.org/SmallFruitsRegGuide/Guides/2016/2016BrambleSprayGuide.pdf

and and article on the disease http://www.smallfruits.org/bramble/pestinformation/caneblightfactsheetii.pdf

Please send in samples to your states disease clinic to confirm any diagnosis.

Phil Brannen, UGA also sent these comments on fields with infected canes:

"On the current canes, there is nothing to be done to prevent it from spreading.  After harvest, I would immediately cut out the old floricanes.  The most full-proof approach to wiping out old inoculum would require complete removal and burning of the old canes.  Some producers hesitate to do this, so complete flail-mowing of the canes may work.  However, I would be careful to say that we don’t have research information to say that this completely destroys the inoculum.  I would tip or pinch prune where possible on the new primocanes, as opposed to large pruning cuts, and I would apply Pristine or Rally (make sure they are labeled for your state) after each day of pruning to prevent infection on the pruning cuts. Hopefully, this will break the cycle."

Red drupelet disorder, Australia updated powerpoint

Max Edgley, from the University of Tasmania, sent me this updated power point last week.

He looked at physical damage, N levels (low/medium/high), cooling temperature treatments. His preliminary data suggests:

• Physical damage increases red drupelet numbers
• High N application during harvest had higher numbers of red drupelets
• Staged cooling (precooling and cooling) had less red drupelets than just one cooling temperature.

For more details on specifics of this work,  see his presentation at:

http://www.utas.edu.au/__data/assets/pdf_file/0009/856422/Red-Drupelet-disorder-update-June-2016.pdf