August 5, 2020

Early August Nursery Update (2nd generation scale hatch and boxwood blight considerations)

This PPA has four updates:

  1. Growing Degree-day Update GDD50
  2. 2nd generation scale insect hatch / crawler growing degree-day targets
  3. Tuliptree and Magnolia scale insect activity and notes on treatment
  4. Late summer boxwood blight considerations

(1) Growing Degree-days as of 8/5/2020

(Weather station selected for each location. Ex: NJ50 = Upper Deerfield)

Upper Deerfield (NJ50)= 2242 GDD50 Howell/Freehold (NJ10) = 1946 GDD50 Pequest (NJ58) = 1901 GDD50

Growth by date

Cornell ForeCast Map

If you need help getting your Growing Degree-day models set up, please contact (twaller@njaes.rutgers.edu) 

(2) 2nd generation scale insect hatch / crawler GDD50 targets

A second generation of scale insects will be hatching soon. Scout for crawlers and treat as needed.

format: scale insect species – (growing degree day GDD50 targets)

  • Maskell scale – (2035)
  • Euonymus scale – (2235)
  • Japanese maple scale – (2508)

Please refer to Tim Waller’s summer scale insect treatments PPA for additional information.

(3) Tuliptree and Magnolia scale egg hatch and crawler activity

Magnolia Scale

Magnolia Scale & Maturing Females Photo- Steven Rettke of RCE

Tuliptree Scale

Tuliptree Scale With Honeydew & Sooty Mold Photo- Steven Rettke of RCE

Tuliptree scale and Magnolia scale insects begin hatching around ~2000 GDD50 but continue to emerge through the month of September (+6 week period). Therefor scouting for 1st and 2nd instar nymphs (crawlers) is critical to controlling these pests. Treatments will be ineffective if made too early in the season, as many of the un-hatched eggs will still be viable and lead to infestation and damages later.

Given this wide window of emergence, three treatment strategies can be deployed

  1. Delay pesticide applications for these pests until mid-October as the females will be dead and not harming the trees, all of the eggs will have hatched, and all of the crawlers will be vulnerable to appropriate materials (best approach)
  2. Apply multiple suppressive sprays at the first sign of emergence (time consuming, labor intensive, costly)
  3. Root or trunk applied systemic insecticides (often for very large trees)

Please refer to Steve Rettke’s Magnolia and Tuliptree scale insect PPA for additional information.

(4) Late summer boxwood blight considerations

As we enter into a period of cooler nighttime temperatures (< 77F) and frequent rain events, boxwood blight preventative sprays should be considered if you have not been making regularly scheduled applications. Boxwood blight is typically not as active during the heat of the summer, however, when cooler temperatures are coupled with prolonged periods of leaf-wetness the pathogen can infect.

Please refer to Tim Waller’s boxwood blight post for additional information and links to many other resources including numerous post from Rich Buckley of the Plant Diagnostic Lab.

 

 

Please take the 2020 Nursery Industry Survey: https://forms.gle/dUjLxaiu6qDQYYsRA

Filed Under: Landscape, Nursery, & Turf, Nursery, Turf
July 23, 2020

Differentiating the Common Wood Borers of Ash Trees

Today, it is understandable for arborists and landscapers to assume that Emerald Ash Borers (Agrilus planipennis) are the cause when they observe branch die-back of ash trees (Fraxinus genus). During the 21st century, this invasive Asian tree beetle borer has killed many 100’s of millions of ash tree species as it has spread across much of the eastern half of the United States. However, it is important to remember some of the other wood borer species that cause ash decline, if not death. This blog will discuss the symptoms to distinguish between the Emerald ash beetle borer, the Ash/Lilac Clearwing moth borer (Podosesia syringae), the Banded Ash Clearwing moth borer (Podosesia aureocincta) and Ash Bark Beetle borers (Hylesinus species). Only the ash bark beetle species will have more than a single generation per season.

Symptoms on ash from banded ash clearwing moth borer infestation. (Photo Credit: Steven K. Rettke of RCE)

[Read more…]

Filed Under: Landscape, Nursery, & Turf, Nursery, Plant Diagnostic Lab
July 21, 2020

Don’t Let Your Guard Down With Farm Worker Health

The COVID-19 pandemic has highlighted the critical, indeed essential, role of farm labor in getting food from farm to plate. However, health concerns should not stop with a negative COVID test, especially if an employee or family member is exhibiting any of the ‘flu-like’ symptoms that are associated with corona virus.

A recent farm call was a reminder that working outside, especially during this July heat wave, exposes workers to a number of potential health risks that may present very similar symptoms and can be equally health, and even life, threatening. Recently published studies from the Rutgers Institute of Earth, Ocean, and Atmospheric Sciences suggest growing numbers of people worldwide are at risk of heat stress and related complications, including farmers and ag laborers working in high heat and humid conditions.

Harvesting and other activities along field edges, including going into the woods instead of using a portable bathroom facilities, also lead to a high risk of tick bites, which can also carry a number of diseases, many as or more debilitating than Lyme disease that most are now aware of. A recent story at Today.com suggested that the COVID-19 pandemic might lead to more tick-borne disease this year, quoting Rutgers entomologist and assistant professor Alvaro Toledo at the Center for Vector Biology with suggestions how to prevent tick bites.

It is critical for your employees’ health and well-being to get proper diagnosis and treatment for all of these ailments. This table illustrates how many tick-born diseases, as well as heat stress, all have potential symptoms very similar to those of COVID-19. Each is linked to additional resources at the CDC. In many cases, it may be the ‘other symptoms’ that may be unique to each disease and assist a medical practitioner with correct identification and lead to better verification with further testing.

   Disease    >

Symptoms  v

 COVID-19 Heat Stress Lyme Disease Ehrlichiosis Babe- biosis Powas-san Rocky Mtn Spotted Fever
Vector* Human Black-legged Tick (a.k.a. Deer Tick) (I. scapularis) Lone Star Tick (A. americanum) & Black-legged Black-legged Tick Ground hog(I. cookei), Squirrel (I. marxi) & Black-legged Ticks American Dog Tick (D. variabilis)
Fever or chills X X X X X X X
Cough X X
Shortness of breath/difficulty breathing X
Fatigue X X X X
Muscle/body aches X X X X X X
Headache X X X X X X X
New loss of taste or smell X
Sore throat X
Congestion or runny nose X
Nausea/vomiting X X X X X X X
Diarrhea X X
Rash X X X
Other symptoms X X X X X X
Potentially Deadly/Disabling
 X X X X X X X

*NOTE – main vector listed, but many tick born diseases may be vectored by other species of ticks, or different species causing same disease may be carried by different tick species.

Filed Under: Blueberry, Commercial Ag Updates, Cranberry, Field, Forage & Livestock, Fruit, Landscape, Nursery, & Turf, Nursery, Strawberry, Tree Fruit, Turf, Vegetable Crops, Wine Grape Tagged With: , , , , , , ,
July 20, 2020

Managing Heat Stress in Nursery and Landscape Plants

With temperatures approaching or exceeding 95oF for many areas of the state, there is potential for heat stress to negatively impact nursery and landscape plants both in the ground and in containers. Most trees and shrubs in our area can begin to experience some degree of heat stress when temperatures exceed 85oF. Several factors can influence the extent of heat stress injury, including the severity and duration of high temperatures, relative humidity, wind, soil moisture status, the age and condition of the plant, and how well the particular species of plant is adapted to dealing with these conditions.

Japanese Maple

Leaf Scorch on Japanese Maple caused by heat stress. Photo Credit.

Heat stress can cause damage to the leaves, resulting in dried or curled edges, as well as reddish or pale coloration as the green chlorophyll pigment begins to break down. This damage may only be superficial, but in some cases it could cause serious injury and death of the leaf tissue. One factor that greatly affects the severity of tissue damage caused by heat stress is the hydration status of the plant before the onset of extreme temperatures.

Plants will naturally dissipate heat through the process of transpiration, provided there is adequate moisture in the soil to support this function. During periods of extreme temperatures, the roots will struggle to draw enough water from the soil to keep up with the rate of water vapor that is exiting the leaves through transpiration. This leads to symptoms such as leaf scorch, curled leaves, discoloration, defoliation, die-back, and temporary wilting. Because the plant is experiencing stress and a disruption in its normal physiological functions, it becomes more susceptible to insect and disease problems.

There are several preventative measures that can be taken to reduce the impacts of heat stress in nursery and landscape plants.

  1. Thoroughly water plants either in the evening or in the early morning before extreme temperatures occur. Water the plants deeply and use irrigation methods that minimize leaf wetness to reduce the potential for foliar diseases.
  2. Properly mulch plants to conserve water in the soil and help lower soil temperatures. Bark mulch, leaf mulch, straw, and other organic mulches will help to lower the temperature in the root zone, while gravel mulches can actually increase root zone temperatures. Be sure to provide additional water to newly mulched plants to prevent dry mulch from taking moisture away from the roots.
  3. Avoid fertilization during periods of heat stress because this can absorb moisture in the root zone and further contribute to dehydration of the plant.
  4. Avoid applying herbicides that can volatilize in high temperatures and drift, causing damage to non-target species.
  5. Pay special attention to plantings that are located next to driveways, concrete patios, or other structures that can absorb and radiate additional heat to the plants. These areas will likely require additional irrigation.

 

Additional Resources:

How to Protect Trees and Other Landscape Plants from Heat Stress

Reducing Heat Stress to Container Grown Plants

Natter’s Notes: Heat Stress

Hot Weather Takes a Toll on Georgia Landscapes

Filed Under: Landscape, Nursery, & Turf, Nursery Tagged With: , , , ,
July 20, 2020

Make Sure Your Farm or Ranch Counts – And is Counted!

Did you know that according to the 2019 State Agriculture Overview for NJ, 3,900 acres of peaches yielded 5/tons per acre at a value of over $25.6 million dollars? Or that 3,500 acres of peppers were harvested in 2019, with a value of $45.8 million dollars?  Or that 9,300 acres of harvested blueberries were valued at $85.3 million dollars in 2019?  And in 2018, NJ ranked 4th nationwide in cranberry and peach production, and third in bell peppers?

[Read more…]

Filed Under: Blueberry, Commercial Ag Updates, Cranberry, Field, Forage & Livestock, Food Safety, Fruit, Landscape, Nursery, & Turf, Nursery, Organic Production, Strawberry, Tree Fruit, Turf, Vegetable Crops, Wine Grape Tagged With: ,
July 17, 2020

Participants Wanted for a Redheaded Flea Beetle Survey

The Southern Nursery Flea Beetle Working-Group has put out a survey under the auspices of University of Georgia. The Universities of Maryland and Delaware recently joined forces with that working group with the goal of gathering information aimed at suppressing this continually destructive pest. If you have seen redheaded flea beetle in your containerized nursery stock please take this short survey. Ultimately the goal is to gather as much information as possible about this pest in an effort to come up with better recommendations for all of us in the industry.

Click here to take the survey

Please contact Tim Waller (twaller@njaes.rutgers.edu) with any questions, severely damaged plant varieties, or personal observations pertaining to pest control and biology.

Thank you

Filed Under: Landscape, Nursery, & Turf, Nursery, Turf, Uncategorized