Berry ‘To-Do’ list:

Occasional heavy rain and hail storms have plagued some areas over the last few weeks.  This, along with temperatures over 90 degrees has made for great disease situation.  But it’s not a freeze!  All things are relative.

We are deploying SWD traps to start monitoring.  This year, under the direction of Anna Wallis, the Fruit Crops IPM coordinator with NYS IPM, we’ll be testing yellow sticky cards along with red cards and the more traditional drowning traps.  The trap findings will be reported in this E-News and on the SWD Blog.  The 2024 SWD Quick Guide of all labeled pesticides – organic and conventional – is available on our website.

Strawberries:

• Most growers have been able to get their Botrytis pre-bloom cover sprays on.  Remember to get the late varieties covered as they reach 10% bloom.  Change your spray material routinely – no more than 2 sprays back-to-back.  Captan is a great chemical to rotate with other materials. Elevate, CaptEvate, and Switch are the most effective during bloom. Captan, Pristine, Scala and Topsin-M are other labeled options for gray mold.
• Anthracnose has been reported in plasticulture strawberries.  Take action immediately if you see the fruit lesions.  More information in an article in this newsletter.
• I have not seen any more tarnished plant bugs since my first find a few weeks ago.  A little unusual, but we have been seeing less pressure each year.  That said, I did find some bud weevil damage and plenty of aphids.  We will start seeing two spotted mites soon, given the heat.  To scout for mites, look at 60 fully expanded tri-foliate leaves and if you find 15 mites you have reached threshold. Start scouting near the farm road side of the field, where there might be some dusty, dry conditions. You may want to spray and then add beneficial predator mites as soon as possible to control these pests.  Predator mites can be used effectively in field hot spots and in tunnels.

 

 

 

Blueberries

• Blueberries need 1-2” of water a week during May and June to support shoot growth. In July you are supporting fruit enlargement.  Don’t forget to irrigate if you aren’t getting enough rain.  And make sure to read the fertigation article in this E-News.  It will be very helpful to those growers that are fertigating.
• We are monitoring for cranberry and cherry fruitworm. Adult emergence may happen this week – adults were found last week in western NY. The adult moths of the cranberry fruitworm lay their eggs at the base of the newly set fruit. The greenish larvae are up to half an inch long and brownish red on the back. Moths of the cherry fruitworm appear late in the blooming season, when the bloom is nearly off. The larvae are three-eighths of an inch long and uniformly reddish orange. Larvae of both species attack the green fruit. Cranberry fruitworm larvae web the berry clusters together and feed inside. Damage from just a few worms is obvious and can be extensive. Two sprays are often required for control; the first should be applied at petal fall and the second 10 days later, about 2 weeks before harvest.  If you have had this pest in the past, sprays should be applied proactively.
• MANY. CARPENTER BEES!!!!!! Although they are nectar robbers, and honeybees like to take advantage of those slits in the corollas, carpenter bees still do some pollinating. It’s just too bad they are also damaging barns, houses and outbuildings.

Brambles:

• Bloom has begun on early floricanes in the Hudson Valley – LOTS of flower buds further north – that will be blooming by soon. Primocane growth is over 3 feet in some areas.
• As leaf tissue expands, watch for orange rust on blackberries and black raspberries and rogue out plants where it is found. I’ve seen more infections this year than I’ve seen in the last 10 years combined.  Orange rust is systemic and cannot be treated to eliminate it from an infected plant. Now is one of the key times for infection on new growth.
• Early pre-bloom sprays for Gray Mold and Powdery Mildew would be wise given the weather. The weather doesn’t make this seem like a priority, but given that each week is so different it might be a good idea.

 Anthracnose on Strawberry Fruit

Source: Penn State Extension, 5/19

Anthracnose is caused by fungi in the genus Colletotrichum, and has been affecting mostly plasticulture plantings, but also matted-row plantings of susceptible cultivars. Some strawberry growers in southeastern PA have already been finding their green fruit to be infected with anthracnose this year, despite cool, wet conditions that would more typically be associated instead with botrytis, our other major strawberry disease. This article attempts to answer some common grower questions regarding anthracnose fruit rot, and how to best manage it.

Symptoms

Berry flowers may be blighted, though this is difficult to tell apart from blossoms blighted by botrytis. Affected berry caps and leaves may show brown or black spots with irregular margins (i.e., spots won’t be perfectly round like with common leaf spot or leaf scorch in early stages), and runners and petioles may show oval to elongated lesions that are brown or black. Tiny orange masses of spores may develop close to the center of these lesions under favorable conditions. Mostly growers notice symptoms on fruit, which may first show up as hard brown lesions when the fruit is green. Seeds may be blackened. Early symptoms on ripe fruit appear as small sunken areas without much color. As the disease progresses and fruit ripens, fruit lesions become sunken and brown, and then an orange coloration develops in the sunken area  as spores are produced.

 

 

 

 

 

 

Where does anthracnose come from?

In most but not all cases, it appears that nurseries are the primary source of the disease, especially for plug plants, but this doesn’t mean that the problems originated with the plug propagator. Plant material used for plug plants sometimes takes a maze-like route through a few states and provinces before finally arriving at a propagator’s greenhouse, and then at the grower’s farm. At this stage, the fungi that cause anthracnose may co-exist within the strawberry plant tissue without causing any symptoms at all (referred to as quiescent or latent infections), until the fungus senses that conditions are right for sporulation. For us in the eastern U.S., this means moisture and high humidity, and moderate to warm temperatures (though this spring, we haven’t had those yet). When sugar level rises as strawberry fruit ripen, the fungus can easily infect and develop lesions on the fruit. Add to that splashing water from rain on plastic that bounces slimy spores around, and suddenly a large proportion of the fruit becomes infected.

How much fungicide resistance is “out there”?

While resistance to some strobilurin (aka QoI) fungicides has been documented in anthracnose, the constantly wet conditions for over a year probably diminished fungicide coverage and effectiveness on grower and nursery farms, causing plenty of inoculum to be present. Spray recommendations have been changed somewhat to minimize resistance development while still obtaining reasonable control (see below) and will continue to be modified as newer materials and information about anthracnose becomes available. It’s also possible that some of the related species discussed in the paragraph above may never have been sensitive to certain fungicides in the first place, rather than developing resistance to them.

Minimize anthracnose with cultural methods

Any cultural method that minimizes rain splash will help, such as using straw mulch along the edges of and between the rows and plants, including in plasticulture. Only a few varieties have significant resistance to anthracnose – ‘Flavorfest’ is less susceptible than ‘Chandler.’ ‘Sweet Charlie’ is somewhat resistant also, but its yields are quite low. Day-neutral varieties are typically very susceptible. Inoculum can be moved around on the equipment and harvester’s hands, so it makes sense to work in less badly affected areas ahead of those where the disease is worse. Low tunnels decrease anthracnose incidence greatly, and high tunnels essentially eliminate fruit symptoms even without the use of fungicides and thus may be especially useful for organic growers.

How should my spray program for anthracnose look?

The spray program recommends keeping a non-systemic protectant (captan) on the plants at the maximum labeled rate ahead of symptom development, starting at 10% bloom and then applying every 7 to 10 days, though wet periods may require shortening the interval. This allows eight applications of captan during the course of a year.

During periods of highest disease pressure, add a group 11 fungicide labeled for strawberries (for example, Abound, Evito or Aftershock, or Cabrio), or better yet, a fungicide that is a combination of group 11 and group 3 (examples are Quadris Top or Quilt Xcel), or group 11 combined with group 7 (such as Luna Sensation, Merivon or Pristine) ingredients to the tank with captan for a maximum of two sequential applications or preferably, two total during the season. Switch (with active ingredients in groups 9 and 12) can be added to captan in the same way but is also limited to two sequential applications during a season. Pre-harvest and re-entry intervals for these products are relatively short but vary, so be sure to check product label information.

 BLUEBERRY Fertigation Guidelines

Dr. Gary C. Pavlis, Ph.D , Atlantic County Agriculture Agent , Rutgers University

Source: The Blueberry Bulletin, Vol. 40, No. 9

Growers have asked me for some guidelines for fertigating blueberries. As you may be aware, our research in New Jersey has shown that fertilizing blueberries a little at a time through the trickle system has shown to be very beneficial. Increases in yield have been seen each year of the research. In addition, increases in fruit firmness have often been seen.

Over the years the following guidelines have been developed:

1. Determine the amount of Nitrogen required/acre/year for each field. Total N should be based on leaf analysis the year before however 60# of Nitrogen/A is a good base recommendation for mature plants if a leaf analysis has not been conducted.

2. Multiply total acres to be fertigated by #/A and convert to total gallons for the season.

3. Fertigation period is 6-8 weeks, starting at ¾ bloom. Fertigate once a week for 1-2 hours during the normal irrigation schedule. Run irrigation a minimum of ½ hour before and ½ hour after fertigation. If travel time from the injection point to the final application point is longer, allow for one hour before and after fertigation time of travel. This will ensure application uniformity to the furthest emitter within the zone. As a rule of thumb, for a scheduled irrigation, irrigate at least 3-4 hour during a 1-2 hour fertigation. Using a 1gph emitter, irrigate 4-6 hours every 3 days, with a .5 gph emitter, irrigate 8-12 hours every 3 days. This is based on no rainfall and ET rates of .2”-.26”/day.

4. Install tensiometers to monitor soil moisture within the 12”-18” root zone depth. For loamy sands and sandy loams irrigate when readings are 20-30 CB on the tensiometers. This will supply needed water and fertilizer to the root zones.

5. Injection pump should be sized for maximum acreage/zone that you plan to irrigate/fertigate at one time ( 2 hour injection time, for a 4 hour irrigation per zone). Example- a 10 acre drip system at 60# N requirement/acre will need 600 gallons of liquid 10-10-10. If injection is scheduled for once a week for 8 weeks, 75 gph injection pump is recommended for a one hour injection period. If you inject for 2 hours, the rate is lower (37.5 gph injection rate). If zones are over 10 acres, plan for between 50-100 gph injection rate. A lower injection rate can be used with a longer fertigation/irrigation period.

Soil Health in Perennial Fruit Plantings – A Statewide Project

Project Background

Interest in soil health has grown in recent years in recognition of the critical role soils play in providing numerous ecosystem services, as well as the influence of human activities on soil health. To date, much of the work around understanding and improving soil health has been conducted in annual cropping systems. Since 2021, a team of researchers and extension educators from around NYS have been collaborating on a statewide soil health effort to assess the status of soil health in NYS orchards. While we continue to work in orchards, we aim to expand this research and extension work to other perennial fruit crop systems including vineyards & small fruit.

Research Questions

• What is the soil health status of perennial fruit crop systems?
• Is soil health the same in perennial vs. annual cropping systems?
• Is there a subset of soil health indicators that best predict fruit yield and quality in perennial fruit?
• What management practices impact soil health indicators in perennial fruit?
• What opportunities exist to improve soil health in NYS perennial fruit crop systems?

Our Approach

We use the Comprehensive Assessment of Soil Health (CASH) test at Cornell University. The CASH test measures physical, biological, and chemical properties of the soil including soil texture, respiration, active C, protein, available water capacity, soil compaction, aggregate stability, pH, organic matter, extractable P, K, total C, total N, and micronutrients. We conduct additional add-on tests as needed depending on the cropping systems (e.g., heavy metals in orchard soils).

We are asking growers to allow us to collect soil samples on their farms and participate in a short management survey to learn about your management practices. CASH test results will be only shared with the individual grower and will be anonymized for broader analysis.

Questions?  Debbie Aller – da352@cornell.edu  (Extension Associate – New York Soil Health Program, Cornell University)