Estimated Water Budget August 10-20

Needless to say, DRY!

Estimated Water Budget August 3 to 9

For virtually the first time this season, continued clear weather throughout the blueberry growing area have made for conditions that would be conducive to irrigation--if not for harvesting. Patchy precipitation is expected for the next three or so days.

Estimated Water Budget July 27 to August 2

Thanks again to ample rain last week, Downeast blueberry soils are generally still plenty moist as of August 2nd.

Blueberry School: Valdensinia leaf spot

Blueberry Hill Farm Headquarters conference room
Wednesday July 29th 6pm to 7pm
Dr. Seanna Annis

Session will demonstrate how to identify the new Valdensinia leaf spot from other leaf spots. Samples with the disease will be on hand for people to look at. Scouting and treatment recommendations will be discussed.

Please bring to the meeting any leaf spot samples (in a sealed plastic bag) you want identified.

Remember: when collecting samples, do not go into a wet field and remove all leaves from your footwear, clothes, and vehicles before leaving the diseased area.

Estimated Water Budget July 20 to July 26

More than enough rain yet again for this past week.

Sanitation to Protect Fields from Valdensinia leaf drop Disease

There is NO tested fungicide that will eradicate this disease from a field. Fungicides will only suppress the disease by protecting the plants. Once in a field, the fungus will produce new spores and infect plants after any 3 day wet period throughout the season. Many fungicide applications will be necessary throughout the prune and crop years to protect plants if this disease is in your field. We want to avoid the trouble (hopefully it is not a disaster) that is hitting growers in Nova Scotia this year from Valdensinia leaf drop disease.

THE KEY IS - DO NOT MOVE ANY DISEASED LEAVES AROUND

• Do NOT walk or drive through any areas of leaf drop or brown leaf spots in a field. Do NOT harvest any area with suspected (or confirmed) Valdensinia leaf drop. Once, confirmed to have the disease, BURN any plants with Valdensinia leaf spot to the ground including burning all leaf litter, as soon as possible.

GENERAL PRECAUTIONS

• At the edge of ANY field you visit, brush leaf litter off of your footwear and vehicle before going to another field. Brush off your footwear and vehicle tires with your hand or something that will NOT collect leaf litter. (If you use a brush, clean it off regularly).

• ALL equipment, vehicles, ATVs, harvesters, blueberry boxes, etc. need to be cleaned off of leaf litter BEFORE they are moved out of a field. All equipment should have no leaf litter on it before you let it into your field. Spraying with a 5% bleach solution (1 part bleach to 19 parts water), other disinfectant or a weak soap solution may help to remove the leaf litter, but may NOT kill the fungus (see below).

• What will NOT WORK - Soaking infected leaves in 10% bleach solution for 1 ½ minutes did NOT kill the fungus! Just dipping footwear or spraying equipment with disinfectant or bleach solution will NOT work, UNLESS the leaf litter is removed.

Please contact Seanna Annis at the Blueberry Hotline (1-800-897-0757) if you have any questions.

UMaine Sustainable Agriculture Field Day July 27

STILLWATER, Me. —University of Maine Cooperative Extension will host its annual Sustainable Agriculture Field Day on Monday, July 27. Designed for farmers, crop advisers and other members of the agricultural community, the event will take place at Rogers Farm, UMaine's 100-acre forage and crops research facility, located on Bennoch Road in Stillwater. Registration will begin at 9 a.m., and events will run until 12:30 p.m. This free event will feature talks on many agricultural topics. Participants will receive one pesticide certification credit and three Certified Crop Adviser credits. For more information,contact Ellen Mallory at 207-581-2942 or John Jemison at 207-581-3241.

UMaine agricultural researchers and Extension faculty members will present their field research on vegetables, grains, and forages. Specific topics will include bread wheat and specialty potato production issues, weed management tools for small-scale vegetable producers, organic fertilizers for sweet corn, and feed and forage rotations for organic dairies. Students from the Black Bear Food Guild will also talk about their community-supported agriculture project.

Presentations will be offered by: Eric Gallandt, associate professor of weed ecolog yand management; John Jemison, Extension water quality specialist; Rick Kersbergen, Extension educator in Waldo County; Lauren Kolb, graduate student in weed ecology; Ellen Mallory, Extension sustainable agriculture specialist; and Marianne Sarrantonio, associate professor of sustainable crop production, in addition to students and members of the Black Bear Food Guild.

EStimated Water Budget July 13-19

Figures 1 and 2 (top and middle) Valdeninsia leaf spots of lowbush blueberry leaves. Figure 3 (bottom) Defoliated stems from loss of leaves infected with Valdeninsia

Valdensinia Leaf spot: NEW Disease in Maine Blueberry Fields

Update as of July 17^th, 2009: Valdensinia leaf spot has been found in commercial blueberry fields in Sumner, Jonesport and Township 24. Please check your fields for this disease.

Valdensinia leaf spot (caused by Valdensinia heterodoxa) causes early leaf drop in lowbush blueberries and in prune fields can cause complete leaf drop so that no flower buds are produced by infected stems. By June 2009, Valdensinia leaf spot had caused complete defoliation in approximately 40 crop and prune fields in Nova Scotia, and had been found in Quebec and New Brunswick fields.

Valdensinia infects all clones of lowbush blueberry and both prune and crop plants. The spots are typically round, large and brown, and can have a “bull’s eye” appearance. Leaves can have from 1 to about 10 spots that can be from ⅛ to ½ inch and larger. These spots rapidly enlarge on the leaves and can spread from stem to stem within a few days. This leaf spot causes early leaf drop, and young leaves drop off when infected by only one spot and while still green. Stems can have complete leaf drop or only have a few infected leaves at the top of the stem. Older infected leaves will remain on the plant until leaf drop in the fall. In prune fields, stems with complete leaf drop will not produce flower buds for the next year. Crop fields with leaf drop will have decreased yields and smaller berries.

The fallen infected leaves are the source of new spores to cause more infections. The spores are large and very efficient at infecting blueberry leaves. The spores can be produced in 2 days on wet, dead infected leaves on the ground. Mature spores are shot off, up to 8 inches high, and typically land on the underside of leaves. The spores will attack all ages of blueberry leaves and will also try to infect all plants they land on so you may see small spots on nearby weeds. The fungus requires about 6 to 8 hours of wet weather (rain or fog) for the spores to infect new leaves. The disease will rapidly spread out from infected stems to adjacent plants as long as the leaf litter remains wet and there is occasionally wet weather for 6 to 8 hours. The fungus survives over the winter in infected leaves. In the spring, about the time of early bloom, it will produce new spores and then leaf infections during the first period of 3 days of wet weather.

Figure 4 (top). Dead leaves with thickened black middle veins where the fungus will survive over the winter. Figure 5 (bottom). Infected blueberries and attempted infections on other plants

Moving ONE dead leaf will spread this disease (see photos below). This disease spreads to new areas of a field and new fields by movement of dead, infected leaves on contaminated footwear, vehicles and equipment including blueberry boxes. NEVER enter a wet field suspected of or having this disease. The dead leaves are sticky and will cling to footwear, vehicles, equipment, boxes, etc. ALWAYS check your footwear for leaves and remove them before leaving any diseased area and do NOT move equipment or drive through diseased areas.

Figure 6 and 7 (top and middle right) A vehicle was driven through a diseased area (bottom of photos) and then driven through healthy areas produced new diseased stems along tire tracks. Figure 8 (bottom left). Walking through the original diseased area and then into healthy areas produced new infected stems in the grower’s footprints.

Precautions for ALL Blueberry Fields

Steam clean all equipment and vehicles before moving them between fields.

Clean blueberry boxes BEFORE they go into your field. Remove all dead leaves stuck to the boxes in a place away from your field and burn the leaf litter.

Key features to identify this disease:

- Large round spots, ⅛ to ½ inch and larger, often look ringed like a bull’s eye on leaves. Typically there are less than 10 spots per leaf, often only 1 to 4.

-Stems with leaf drop, particularly of lower leaves. Early in the season, young leaves will fall off while still green.

If you find this disease in your field

- Do not enter the field when it is wet, Remove dead leaves from your footwear before leaving the diseased area (so you do not spread it around the field)

- Flag off the infected area so no one walks through it or moves equipment through it

- Check your vehicles or other equipment that may have come in contact with the infected area for dead leaves. Steam clean all equipment and vehicles before moving them between fields.

- Contact Seanna Annis or Dave Yarborough to confirm and report disease (Blueberry Hotline: 1-800-897-0757)

- Once disease is confirmed follow treatment recommendations below.

Be careful to NOT move dead infected leaves around the field or between fields even after treatment.

For Prune fields: As soon as presence of the disease is confirmed, BURN the diseased area and a 10 ft area outside the edge of the infected stems with a hand-held burner or by placing straw on the infected area. Burn around edges of the area first, and then move into center of diseased area. You do not need to burn your whole field unless your whole field is affected by the disease. The diseased stems produce few, if any, flower buds for the crop year and burning early will help prevent spread of this disease to other areas in the field.

For Crop fields: Do NOT harvest areas with disease and do NOT move any equipment through diseased area. As soon as presence of the disease is confirmed, BURN the diseased area and a 10 ft area outside the edge of the infected stems with a hand-held burner or by placing straw on the infected area. Burn around edges of the area first, and then move into center of diseased area. You do not need to burn your whole field unless your whole field is affected by the disease.

In the Spring of Next Year: From early bloom on, check plants in infected field, particularly in the infected area, for leaf spots after the first period of 3 days of wet weather. If you see any leaf spots, apply the fungicide that will be recommended in 2010 Disease Control Guide for Wild Blueberries as soon as possible and before the next wet period.

Prepared by Dr. Seanna Annis, Blueberry Pathologist, School of Biology and Ecology, and Dr. David Yarborough, Extension Blueberry Specialist, University of Maine, Orono, ME, USA with information provided by Dr. Paul Hildebrand, Plant Pathologist, Atlantic Food and Horticulture Research Centre, Agricuture and Agri-Food Canada, 32 Main St. Kentville, NS, Canada

Estimated Water Budget July 2 to 12

Tensiometers at Jonesboro, Deblois and Northfield (all sandy loams) were all reading between 9 and 12 cb around 1 PM today. Heavy rains later this afternoon are likely to lower these readings to around 5 cb or so. So soils are still plenty moist as we end the second week of July. See you all at Blueberry Hill farm day this Wednesday.

Estimated Water Budget June 25 to July 1, 2009

Soils were wet but not water logged at most of my study sites as of yesterday. Tensiometers at the sandy loam and loamy sand sites all read between 8-11 cb. At one lowland site in Northfield however the water table was within approximately 2 feet of the surface. This site has shown a propensity for flooding, likely due to it's elevation, proximity to a lake and relatively fine textured soil.

With respect to the precipitation recorded for Cherryfield, my rain gauge appears to be consistent with those posted online for the immediate vicinity.

Estimated water budget June 17-24

Well there's 8 days of data here instead of 7--with all of the rain lately it hardly matters. The precipitation amounts for Cherryfield in this table look a little low so I'll be checking that gauge next time I'm out there. Is the sun ever going to shine again?!!

Estimated Water Budget June 10-16, 2009

Ample rain this past week replenished the soil moisture throughout blueberry country. Smooth sailing for awhile.

Estimated water budget for June 3-9, 2009

In contrast to the previous week, there was little to no rain and a moderate amount of evapotranspiration at all sites for the week of June 3-9. Tensiometers and Watermark moisture probes at Blueberry Hill and other sites generally indicated that the soil was close to requiring irrigation. Due to the low temperatures and the high propability of precipitation forecast for the next few days I chose yesterday to postpone irrigation until the current front passes. I will be returning to Blueberry Hill on Friday to re-evaluate soil moisture conditions. Stay tuned.

Water budget for the week of May 27 to June 2

Lots of rain and not a whole lot of evapotranspiration this past week. Tensiometers on June 2 at Jonesboro, Deblois and Jonesport all indicated plentiful soil moisture.

Blossom Blight Forecast for Friday, May 29th

The rain and fog we had over May 27th to 28th was NOT long enough for infection by the Botrytis fungus that causes blossom blight. The average temperatures were about 43 to 48F and the rain was only for about 24 hours. At 46F the fungus needs at least 36 hours of rain to cause moderate to high infection. There is a very low risk of less than 10% of the blossoms becoming infected with this last wet period, and this is NOT enough to cover the cost of fungicide applications.

Any dead blossoms you are currently seeing on your plants are caused by mummy berry disease, since this fungus can attack both leaf and flower buds.

For more information on Blossom blight caused by Botrytis please see Fact sheet # 212.

Estimated Water Budget May 20-26

As illustrated by the table below, the rain forecast for the next couple of days will help replenish soils that were beginning to dry. Tensiometer values in Deblois and Jonesboro were near -15 cb yesterday. We irrigate the sandy loam soils in our experimental plots at Blueberry Hill Farm when the tensiometer values there reach -20 cb, so we were getting close to a relatively early-season irrigation.

Estimated Water budget May 19-25

Month Day--Machias --Newport--Ellsworth--Waldoboro--Cherryfield
.....................ET...Rain--ET...Rain--ET..Rain---ET...Rain----ET...Rain
May 19----0.09..0.01---0.11...0---0.09...0-----0.09...0------0.11...0
May 20----0.10.....0----0.11....0---0.12...0-----0.10...0------0.12...0
May 21----0.13......0----0.14...0---0.14...0-----0.13....0------0.16...0
May 22----0.12.....0----0.12...0----0.15...0-----0.13....0-----0.15....0
May 23----0.09.....0----0.10...0---0.10...0-----0.08...0------0.11....0
May 24----0.10..0.01--0.12..0.04--0.12..0.09--0.10...0.16---0.13...0.02
May 25----0.10..0.01--0.10....0---0.11..0.02---0.10...0------0.112...0

sum------0.72..0.03--0.80..0.04--0.84..0.11---0.72...0.16---0.89...0.02

Maine Wild Blueberry Irrigation Information

Hello everybody. Throughout the 2009 growing season, I will be posting estimates of wild blueberry daily water use (ET) and precipitation totals for 5 sites throughout Down East, Maine. The estimates of water use given below were calculated from weather data using the Penman-Montieth reference evapotranspiration equation, with the resulting values adjusted for wild blueberry. In all cases the values are given in inches of water per day or week. Because there was generally ample rain for the first two weeks of May, those values are given on a weekly basis for illustration purposes. From this point in the growing season on, values of ET and rain will be given for each day to allow growers the ability to monitor soil water deficits as they occur. This blog will be updated 2-3 times a week. It is important to realize that the ET values given here are estimates only, and that soil properties strongly influence soil water availability (see Wild Blueberry Fact Sheet 631 http://www.wildblueberries.maine.edu/PDF/Production/631.pdf).

Machias Newport Ellsworth Waldoboro Deblois
ET rain ET rain ET rain ET rain ET rain
WEEK OF:
May 1-7 0.45 0.34 0.58 1.14 0.56 1.28 0.50 1.33 0.60 0.56

May 8-14 0.58 1.01 0.68 0.91 0.69 0.88 0.57 0.78 0.71 0.58

DAILY
May 15 0.09 0.02 0.11 0 0.11 0.01 0.09 0.01 0.12 0.02
May 16 0.08 0 0.11 0 0.10 0 0.07 0.01 0.11 0
May 17 0.08 2.13 0.09 0.31 0.09 0.87 0.08 0.66 0.09 0.36
May 18 0.06 0.12 0.07 0 0.07 0 0.06 0 0.08 0.03
May 19 0.09 0.01 0.11 0 0.09 0 0.09 0 0.11 0

Tensiometers are being installed in fields near Cherryfield and Jonesboro today, and information from these instruments will be posted here on a biweekly basis as a means of supplementing the data above.

Mummy berry forecast for Monday May 18th to Wednesday May 20th

Regions near Belfast
Mummy berry cups were still producing spores before the weekend. The cups were finished by Sunday in a wet field in Belfast. This indicates the cups are probably finished in fields near this area.

Hancock and Washington counties
Mummy berry cups were still producing spores over the weekend but are starting to die off in fields near Deblois, Cherryfield and Jonesboro. The cups will likely to be finished producing spores by Wednesday in these areas, unless you have a particularly cool or wet field.
The frost forecasted for Monday night would need to be accompanied by at least 12 and up to 24 hours of leaf wetness to cause infection, which is not predicted for Monday night .
The forecast is for no significant rainfall in the next two days so there is little chance of infection periods occuring during the next two days. Fog may still cause a infection period so check Factsheet #217 for chance of infection if fog does occur in your field in the next two days.
Remember you have 7 to 10 days of protection from your last fungicide application so your plants will still be protected if you have applied fungicide on Friday May 8th or after that date.

Plan on the putting a mummy berry patch in your field this August
The only way to be completely sure of when mummy berry cups are starting to produce spores and when they are finished in your field is to put out 2 to 3 mummy berry patches in your field. Local conditions in a field can vary so we suggest multiple patches to make sure one of them works and develops cups. The patches can be close to each other (within 10 ft). We have found that slight hollows that may be damp, but are not in the route of water run-off work well. Collect about 100 mummy berries before harvest, and choose two (or three) areas of slight hollows in a field that will be in crop next year. Clear the leaf litter from each area (2" by 2") and then put down about 1/2 the mummy berries and press them into the soil with your foot. Then add about 1/4" of soil and press down some more. Mark each spot with stakes on either side so you can find them in the spring.

Any questions contact Seanna Annis via the Blueberry Hotline (disease choice).

Mummy berry forecast for Thursday May 14 to Friday May 15th

Regions near Belfast, in Waldo county, Hancock and Washington counties

Mummy berry cups are still producing spores in these areas. Unfurled leaf buds and flowers are still susceptible. All leaf and flower buds are still susceptible as long as the fungal spores are present.

There has not been an infection period in any of these areas since Sunday night.

However, there is likely to be an infection period on Thursday through Friday in most areas. With the warmer temperatures, the fungus needs less length of time with plant wetness to penetrate into the plants. The temperatures are predicted to be in the low 50s to the 40s overnight on Thursday. At 43 F the fungus needs at least 10 hours of plant wetness to get into the plant, and at 50 F, at least 8 hours of plant wetness.

If you have applied fungicide within the last 7 to 10 days (Tuesday May 5 through to Thursday May 14th), your plants will still be protected during the infection period Thursday night, so you do not need to apply fungicides.
If you applied fungicides before Tuesday May 5th your plants may get infected by the mummy berry fungus during Thursday night. You have 72 hours to apply fungicide after the beginning of the infection period (rain or fog) in your field to kill off any fungus that has penetrated your plants.

Factsheet #217 has more information about the mummy berry forecasting method and lengths of time of rain or fog and temperature to have infection periods.

Factsheet #219 contains this year's recommendations for using fungicides to control mummy berry disease.

Mummyberry Forecast For Monday May 11 to Tuesday May 12th.

Lincoln and Knox counties
Mummy berry cups were still actively producing spores over the weekend. There were two infection periods, one on Saturday night and one on Sunday night. The cups appear to be drying up today (Monday). The fungus probably is finished producing spores in most of these areas unless you have a particularly cool or wet field.

Waldo, Hancock, Penobscot and Washington counties
Mummy berry cups are still actively producing spores in Waldo, Hancock, Penobscot, and Washington counties. There were infection periods over the weekend in these areas.

Your plants will have been protected over the weekend if you applied fungicide on Friday May 1st or after that. The recommended fungicides will protect plants for approximately 7 to 10 days after application.
If your last application of fungicide was before May 1st, then you have 72 hours from the start of the rain or fog on Saturday evening to apply fungicide and still control the fungus. For example, if it started raining on Saturday May 9th at 7pm in your field you have until Tuesday May 12th at 7pm to apply fungicide to control the disease.

There is currently forecasted a less than 50% chance of rain on Thursday and Thursday night, so there may not be any more infection periods this week due to rain, but fog in localized areas may still be a problem.

Whether there was an infection period depends upon the length of plant wetness caused by continuous rain and fog in your area and the temperature during the plant wetness. Please check the chart in Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of plant wetness.

Please check Factsheet #219 for current mummy berry control recommendations.

Mummyberry Forecast For Friday, May 8th through Sunday, May 10th.

Lincoln and Knox counties
Mummy berry cups are likely still actively producing spores particularly in northern portions of these counties and later (cooler or wetter) fields. As long as the fungus is producing spores, there is a risk of mummy berry fungus infection.

Waldo, Hancock, Penobscot and Washington counties
Mummy berry cups are actively producing spores in Waldo, Hancock, Penobscot, and Washington counties.

There have been a series of infection periods over the last 3 days. Your plants will be protected for approximately 7 to 10 days after you apply fungicide. So if you applied fungicide last week (Monday April 27 or after) your plants were probably still protected this past week (Monday May 4th through Friday May 8th).

There is rain forecasted for late Saturday through Sunday in most blueberry growing areas and if the temperature and length of rain forecasted occurs this will be another infection period for the fungus.
Remember you have 72 hours from the START of the rain/fog period to apply fungicide, if necessary, in your field.

Whether there was an infection period depends upon the length of plant wetness caused by continuous rain and fog in your area and the temperature during the plant wetness. Please check the chart in Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of plant wetness.

Please check Factsheet #219 for current mummy berry control recommendations.

Mummy berry forecast update Tuesday May 5th.
Mummy berry cups are still actively producing spores in the Union and Belfast areas, as well as most blueberry growing areas in Lincoln, Waldo, Hancock, Penobscot, and Washington counties.

Rain is forecasted for the next few days, so there will likely be another infection period in most blueberry growing areas.
Whether there was an infection period depends upon the length of plant wetness caused by continuous rain and fog in your area and the temperature during the plant wetness.
Please check the chart in Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of plant wetness.

IF you need to apply fungicide, remember it needs to be applied within 72 hours of the START of the rain/fog period in your field to control the fungus that got into the plants during this last infection period.

Please see Factsheet #219 Wild Blueberry extension site (http://wildblueberries.maine.edu) for recommended disease control methods.

Mummy berry forecast update Sunday May 3rd.
Mummy berry cups are likely still actively producing spores in most blueberry growing areas in Lincoln, Waldo, Hancock, Penobscot, and Washington counties.

With the rain over Friday and Saturday, there was likely an infection period in most blueberry growing areas.
Whether there was an infection period depends upon the length of plant wetness caused by continuous rain and fog in your area and the temperature during the plant wetness.
Please check the chart in Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of plant wetness.

If you applied fungicide approximately 7 to 10 days before (anytime from Thursday April 23rd to Friday May 1st) then your plants are STILL protected and you do NOT need to reapply fungicide for control of this last infection period.

IF you need to apply fungicide, remember it needs to be applied within 72 hours of the START of the rain/fog period in your field to control the fungus that got into the plants during this last infection period.

Please see Factsheet #219 Wild Blueberry extension site (http://wildblueberries.maine.edu) for recommended disease control methods.

UPDATED FORECAST FOR DOWNEAST Wednesday April 29, 2009

UPDATE:
There was a infection period due to heavy fog in the Downeast area, (Deblois, Cherryfield, Jonesboro, Jonesport) on Monday night. The fog started in most areas around 9pm and lasted to around 7am on Tuesday morning.

Mummy berry cups are present and producing spores in this area.
Please check your field to see if you have enough susceptible plants (more than 40% of random stems with flower buds are in the flower bud crown stage) to make an application of fungicide cost effective.

To control this disease you should apply fungicide within 72 hours of the START of the rain/fog period in your field. For example if you choose to apply fungicide, you have until 9pm on Thursday April 30 to control any fungus that got into the plant on Monday night. If you apply fungicide on Thursday, the fungicide will also provide protection through the predicted storm this weekend.

Remember whether infection did occur in your field will depend upon 1) how far along the plants are in your field, 2) the actual temperature during, and length of time of rain or rain and fog in your field, and 3) of course, have you had mummy berry disease in your field in previous years .

Please check Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of leaf wetness. Please see Factsheet #219 for recommended disease control methods.

UPDATED FORECAST FOR MUMMY BERRY FOR ALL REGIONS Tuesday April 28, 2009

UPDATE: Union, Rockport, Camden area.
There has been an infection period in the Union area. There was long enough rain (more than 8 hours at 48 F) over Monday night and morning for an infection period to have occurred. There are still active mummy berry cups in fields in these areas. Most plants are likely susceptible to the fungus now. To control this disease you can apply fungicide within 72 hours of the START of the rain/fog period in your field. For example if the rain started in your area at 9 pm on Monday you have until 9pm on Thursday of this week to apply fungicide to control the infection.

Belfast, Orland areas
Mummy berry cups are now active in your area. Most plants are close to or are susceptible by now.

NEW: Downeast area, (Deblois, Cherryfield, Jonesboro, Jonesport)
Mummy berry cups are just getting started in this area, but some cups are large enough to be spreading spores. Please check your field to see if you have enough susceptible plants (more than 40% of random stems with flower buds are in the flower bud crown stage) to make an application of fungicide cost effective IF an infection period occurs.

IF your plants are at the susceptible stage AND your field gets FOG you may get an infection period. Please look at the chart in Factsheet #217 to check the length of time for plant wetness and temperature during that period.

ALL AREAS
There is a chance of new infection periods sometime from Tuesday through Wednesday morning with the storm coming through. This will depend on the length of time you have rain and fog in your field and the temperature during this time. At 65 F you need 8 hours of rain and fog, but at 72 to 80 F, which is forecasted for some areas Tuesday, the fungus only needs 3.5 hours of plant wetness to get infect the plants.

You will need to keep track of the approximate length of time of continuous rain and fog in your area and the temperature during the rain and fog to tell whether your field has had an infection period.

To control this disease you should apply fungicide within 72 hours of the START of the rain/fog period in your field. For example if the rain started in your area at 5 am on Tuesday you have until 5 am on Friday of this week to apply fungicide to kill off the infection and protect your plants.

Remember whether infection did occur in your field will depend upon 1) how far along the plants are in your field, 2) the actual temperature during, and length of time of rain or rain and fog in your field, and 3) of course, have you had mummy berry disease in your field in previous years .

Please check Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of leaf wetness. Please see Factsheet #219 for recommended disease control methods.

Mummy Berry Forecast for Monday April 27 to Wednesday April 29th

For Knox, Lincoln, Waldo and southwestern Hancock.
Union, Rockport, Camden area.
There are still active mummy berry cups in fields in these areas. Most plants are likely susceptible to the fungus now.

Belfast, Orland areas
Mummy berry cups are now active in your area. And if you have an early or particularly wet field, they may have been active by yesterday (Sunday April 26th). Most plants are close to or are susceptible by now. IF your plants are susceptible, more than 40% of stems had flower buds at the crown stage (please see post on Monday April 20th on how to evaluate this).


Overall forecast for Knox, Lincoln, Waldo, southwestern Hancock
There was little chance of an infection period within the last 3 days, since few fields were likely to have rain longer than 6 hours (the minimal length of plant wetness required to get infection at 65 F). IF your field had FOG you might have had an infection period. Please look at the chart in Factsheet #217 to check the length of time for plant wetness and temperature during that period.

There is a chance of infection periods sometime within Monday night through to Wednesday morning, depending upon whether you have fog or rain in your field and the temperature. The chart below show the plant wetness up to 65 F. At 72 to 80 F, which is forecasted for some areas Tuesday, the fungus only needs 3.5 hours of plant wetness to get infect the plants.
You will need to keep track of the approximate length of time of continuous rain and fog in your area and the temperature during the rain and fog to tell whether your field has had an infection period.
IF your plants are susceptible, more than 40% of stems had flower buds at the crown stage (please see previous post on how to evaluate this), AND you have had mummy berry disease in that field before, then the fungus could have infected your plants.

To control this disease you should apply fungicide within 72 hours of the START of the rain/fog period in your field. For example if the rain started in your area at 5 am on Tuesday you have until 5 am on Friday of this week to apply fungicide to kill off the infection and protect your plants.

Remember whether infection did occur in your field will depend upon 1) how far along the plants are in your field, 2) the actual temperature during, and length of time of rain or rain and fog in your field, and 3) of course, have you had mummy berry disease in your field in previous years .

Please check Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of leaf wetness. Please see Factsheet #219 for recommended disease control methods.

Mummy Berry Forecast for Wednesday April 22nd
For Knox, Lincoln and lower Waldo county.
There has been an infection period for the mummy berry fungus in most of the region around Union, Rockport area.
IF your plants are susceptible, more than 40% of stems had flower buds at the crown stage (please see previous post on how to evaluate this), AND you have had mummy berry disease in that field before, then the fungus could have infected your plants.

With the rain and heavy fog in this area there will have been long enough period of leaf wetness for the fungus to have infected the leaf and flower buds. To control this disease you should apply fungicide within 72 hours of the start of the rain/fog period in your field on Tuesday. For example if the rain started in your area at 5 am on Tuesday you have until 5 am on Friday of this week to apply fungicide to kill off the infection and protect your plants.

Remember whether infection did occur in your field will depend upon 1) how far along the plants are in your field, 2) the actual temperature during, and length of time of rain or rain and fog in your field, and 3) of course, have you had mummy berry disease in your field in previous years .

Please check Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of leaf wetness. Please see Factsheet #219 for recommended disease control methods.

Mummy Berry Forecast for Monday April 20th to Tuesday April 21st
For Knox, Lincoln and lower Waldo county.
Mummy berry cups producing spores were found in South Hope on Wednesday April 15th. The blueberry plants were not susceptible at that time since less than 40% of stems had flower buds at the crown stage.

There is a chance of an infection period occurring around the Union area with the rain forecasted to start Tuesday night. Whether infection does occur will depend upon the actual temperature during and length of time of rain or rain and fog in your field.

Whether you need to spray fungicides for mummy berry control will also depend upon how far along your plants are. IF more than 40% of random stems (4 out of 10) in your field have buds at the crown stage (see photo) your plants are now susceptible to the fungus.

If the weather forecast suggests rain or rain and fog for longer than 10 hours you should check the forecast for the temperature during that period. AT about 36 F, 24 hours of leaf wetness is required for infection. At 43 F, only 10 hours of leaf wetness is required to cause infection.

Please check Factsheet #217 at the Wild Blueberry extension site (http://wildblueberries.maine.edu) for more information on the chance of infection depending upon temperature and length of leaf wetness. Please see Factsheet #219 for recommended disease control methods.

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