Author: acimovic

First Rust and Secondary Powdery Mildew Symptoms Visible on Apple Leaves in Winchester VA

First Rust and Secondary Powdery Mildew Symptoms Visible on Apple Leaves in Winchester VA

All the major apple fungal diseases in the Shenandoah Valley are visible, except apple scab. This morning I found first fresh rust (Fig. 1, 2) and powdery mildew (Fig. 3) infections of this season on unsprayed ‘Ginger Gold’ and ‘Pink Lady’ trees here at AREC. 

First Blossom Blight Symptoms Visible in Winchester at AREC Trial (Infections 23-25 April)

First Blossom Blight Symptoms Visible in Winchester at AREC Trial (Infections 23-25 April)

(I) In our research trial at AREC we detected today first fire blight symptoms on 17 May on ‘Fuji’ flower clusters and shoots. We inoculated whole ‘Fuji’ trees with fire blight bacterium Erwinia amylovora on 23, 24, and 25 April (late April heat wave) at 

Kick-back Materials for Last Major Scab Infections 6 & 7 May; Primary Scab Season Is Over But Rusts Continue; Fire Blight Infection 4, 5 or 7 May

Kick-back Materials for Last Major Scab Infections 6 & 7 May; Primary Scab Season Is Over But Rusts Continue; Fire Blight Infection 4, 5 or 7 May

1. The primary scab season in Virginia is over as the ascospore reserves have been depleted from the leaf litter below 5%. The 6 and 7 May heavy rain events have triggered the last severe primary scab infection and if you did not cover with 

1. Fire Blight Infection Possible May 2-4 Depending on a Location; 2. Scab, Rust, Powdery Mildew Still Relevant Threats

1. Fire Blight Infection Possible May 2-4 Depending on a Location; 2. Scab, Rust, Powdery Mildew Still Relevant Threats

1. In and near Winchester, the NEWA’s EIP model is calling for infection on 4 May with the thunderstorm rain events we might get this afternoon, evening or tomorrow morning. In central Virginia, apple orchards are at or past petal fall, so any late blooming 

A Few Points on Strep Use and Options for Using Apogee/Kudos in Shoot Blight and Canker Management on Apple

A Few Points on Strep Use and Options for Using Apogee/Kudos in Shoot Blight and Canker Management on Apple

1. Blossom Blight Management – Follow Up on Recent Specific Questions Apply streptomycin with Regulaid or LI700 just before or within 24 h after the wetting event that is predicted by RIMpro and/or Maryblyt (Infection Potential EIP value in NEWA) to allow fire blight infection. 

1. Warning: Fire Blight Infections Predicted for 23, 24, 25 or 26 April Depending on Where Rain Occurs; 2. Keep Looking at The EIP Model in NEWA to Decide on Strep Application

1. Warning: Fire Blight Infections Predicted for 23, 24, 25 or 26 April Depending on Where Rain Occurs; 2. Keep Looking at The EIP Model in NEWA to Decide on Strep Application

Currently, the 72 h ahead radar (72-Hour Future Radar) indicates that thunderstorm showers are predicted to impact Winchester, VA, and surrounding areas on 24 April triggering the infections on both 24 and 25 April (dark red fields with EIP equal or above 100 in print 

Warm Weather Ahead: Predicted Favorable Conditions for Fire Blight 23-26 April, But Infections Only if Wetting Occurs

Warm Weather Ahead: Predicted Favorable Conditions for Fire Blight 23-26 April, But Infections Only if Wetting Occurs

Weather forecast as of this moment is predicting warm weather ahead with average temperatures above 60F, which will ramp up the value of the EIP above 100 on 23rd or 24th April. The EIP value is the measure of the infection potential of the fire 

WARNING for All Virginia Locations: Fire Blight Infection Predicted for Wetting Event 14 April on any Apple and Pear Trees in Bloom

WARNING for All Virginia Locations: Fire Blight Infection Predicted for Wetting Event 14 April on any Apple and Pear Trees in Bloom

As the NWS weather forecast for 14 -15 April has changed as of this morning, and I warned you in the last 3 days that fire blight risk is high, now the NEWA EIP issued “INFECTION” warning in red box on 14 April (see print 

Central and South VA in Apple Bloom – Look at MaryBlyt’s EIP Value in NEWA’s Fire Blight Model for Fire Blight Spray Considerations

Central and South VA in Apple Bloom – Look at MaryBlyt’s EIP Value in NEWA’s Fire Blight Model for Fire Blight Spray Considerations

(I) FIRE BLIGHT: Apple bloom started on early cultivars on 1st April (Tyro) or 4th April (Charlottesville) or 6th April (Fincastle) and it varies from location and your orchard elevation. We are at very early bloom in ‘Pink Lady’ in Winchester (less then 1 %). 

Major Scab and Juniper Rust Infections Predicted from 6 to 9 April in Winchester Area

Major Scab and Juniper Rust Infections Predicted from 6 to 9 April in Winchester Area

Apples are at Tight Cluster or somewhat beyond on early cultivars at in Winchester. From 6 – 9 April 2022, we are expecting multiple rain events followed by the slow drying conditions as per the NWS forecast with the warmer periods peaking up to 64F