Search Results for: corn borer

Sweet Corn Insect Pests:
European Corn Borer

European corn borer (ECB) is one of the three major caterpillar pests of sweet corn. ECB has two to three generations per year in New Jersey. Adult moths emerge in late April and May, mate and begin laying eggs on the undersides of corn plants. Typically, eggs are laid on whorl stage plants. Damage occurs as larvae hatch and bore through the leaves to get to the center of the stalk where the tassel is forming. As the plant progresses to the pre-tassel stage, ECB larvae may be found feeding in the newly emerged tassels. Once the tassel spreads and begins to shed pollen, larvae migrate down the stalk and bore back into the stalk at leaf axils or into the developing ears. The latter event results in unmarketable ears.

Find adult ECB population activity (population maps and interpretive information as well as current occurrence and severity of crop damage) published throughout the growing season at:

 
It is important that growers use the above sites to determine when to begin field scouting. While sweet corn plants can tolerate significant injury when in the vegetative stages, ECB must be controlled prior to the development of ears or that marketable portion of the crop will be lost.

The first generation of the year, when larval damage peaks in mid-June is typically the most difficult to manage. It is often not possible to eliminate the threat with one insecticide application; however the most critical application is one timed for the plant’s transition from pre-tassel to full tassel. This is when there is maximum exposure of the larvae to the spray material. If the number of plants infested is above 12% at any time prior to full silk, an insecticide application should be considered. After the planting is in full silk, the majority of ECB larvae still alive will have bored back into stalks or ears and will be unreachable by sprays. See the NJ Commercial Vegetable Production Recommendations for labeled insecticides.

Ambrosia Beetle Borers of Nursery Plants

General Overview:

There are 30 non-native ambrosia beetle species in North America but only a half dozen are serious insect pests within nurseries, pecans & apples. The Xylosandrus species of beetle borers are native to southeast Asia & were first reported in the United States during the early 1930s (black stem borer). Today they are found in 29 states. Two ambrosia species found in NJ nurseries cause serious damage to trees. (1) The black stem borer (Xylosandrus germanus) (~2 mm) has attacked more than 200 tree species (fig.1). (2) The granulate (Asian) borer (Xylosandrus crassiusculus) (~2.5 mm) has attacked more than 120 tree species (fig.2). Both species are a threat to trees that are stressed. A 3rd species, the invasive redbay ambrosia beetle (Xyleborus glabratus), was first found in Louisiana in 2014. A major difference is it will also attack trees not under stress. It is not presently found in NJ, but it is moving north. The concern is the impact it may have on sassafras forests.

Fig. 1: An adult female ambrosia black stem beetle borer. Photo Credit: Brad Barnd, Bug Guide.net

Fig 2: An adult female ambrosia granulate borer. Photo Credit: Alabama Coop. Ext.

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High Probability of Downed Droughty Corn During Hurricane Season

The national oceanic and atmospheric agency at Colorado University has released their forecasting for the next two months of the Hurricane and Tropical Storm Season. The strong La Nina is persisting into a third year coupled with decreasing water temperatures returning closer to normal for this time of year are reportedly similar to 1999, 2000, 2011 and 2021 conditions.

Field corn: The stalk stability of droughty corn is much less tolerant to high winds than non-droughty corn. Given the drought conditions, corn producers may have the ability to harvest corn earlier than normal due to rapid dry down on the cob. Current soil moisture conditions are very suitable for fitting fields for winter small grain establishment.

Moldy cornAspergillus mold species often show up after drought conditions, posing a significant risk of aflatoxins in the corn crop if present. Aspergillus molds are carcinogenic to people and cause losses in livestock and poultry. Combine operators and elevator operators should take precautions against inhaling fungal spores. Signs of Aspergillus ear rot include evidence of powdery olive-green mold on the ear tip or on kernels in the ear.

Corn with brown spots

Fusarium ear rots are also probable in fields that had significant high humidity and high temperatures as grains are developing to black layer. Fusarium molds show up as white to pink cotton-like growths mold scattered throughout the ear. A starburst like pattern may occur on infected kernels that may also be brown in color.

*Inhaling poison ivy volitile oils and ivyleaf morning glory and jimson weed dust as they go through the combine along field edges should also be avoided. 

For additional images see https://cropprotectionnetwork.org/encyclopedia/aspergillus-ear-rot-of-corn

Hurricane Season: Hurricane forecasters have stated that this La Nina and nearer to average water temperatures are similar to 1999, 2000, 2011 and last year. Given that in 1999, 11.41 inches of rain fell in Salem County; and in 2000, 5.76 inches fell in Salem County; and in 2011, 6.19 inches fell in Salem County in the month of September, producers who can harvest early may want to consider higher moisture harvest if standability is an issue. Hurricane season peaks from mid-August to mid-October with the season ending on Nov. 30.

Soybeans: Soybean fields should be walked for signs of stem snap in areas with high levels of soybean stem borer activity in 2020 and where July herbicide applications visibly stressed plants during the height of the drought this season. Due to in season stresses, bean maturity in the pods may be farther along in some fields than leaves indicate. If 90% of the beans are tan, test moisture levels frequently.

Salem County producers can pick up mycotoxin plant analysis bags at the extension office. Current pricing from regional laboratories are as follows:

1. NJ Department of Agriculture website submission form: (click link)

Mycotoxin test. Please call the laboratory to check on current availability and pricing

 

2. Dairy One Mycotoxin Testing: (click link)

  • Mycotoxin Panel $105: Aflatoxin B1, B2, G1, G2, Vomitoxin, Zearalenone, T2, 3-acetyl DON, 15-acetyl DON
  • Ochratoxin A $77
  • Fumonisin B1, B2, B3 $77
  • Full Panel $210

3. Dairyland Laboratories Individual Toxins: (click link)

  • Aflatoxin  $55.00
  • Vomitoxin (DON) $55.00
  • Zearalenone $55.00
  • T-2 /HT2 $55.00
  • Fumonisin  $55.00
  • Ochratoxin $55.00

Check out the historical storm map maker image below at https://spacecoastdaily.com/2019/08/noaa-historical-hurricane-tracks-explore-more-than-150-years-of-historical-hurricane-landfalls/

July Pest Scouting Nursery, Landscape, and Christmas Trees – Key borer and scale insect control timings

Pest Scouting – Please refer to these documents for a full listing of insects pests for your area corresponding to growing degree-days (GDDs). 

Quick look guides for July (Borers and Scales) and (All other) 

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

The following key groups of pests will be active, vulnerable, or otherwise treatable during the next month throughout most of NJ. Here, scale insects and borers with key life stage events during the 1000-2500 GDD timeframe are discussed. Note there are many other insect pests present this time of year so please view the pest scouting guides above for your particular needs.

Projected GDD50 Accumulation as of July 13 2022 Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region Location Station 13-Jul 1-Aug 1-Sep
South Upper Deerfield NJ50 1598 2115 2905
Central Howell / Freehold NJ10 1383 1871 2594
North High Point NJ59 1132 1541 2138
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information 

BORER Insect Activity for 1000-2500 GDD (~ July)
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Many Roundheaded appletree borer Saperda candida 802 1129 RU Adults
Ash Emerald ash borer Agrilus planipennis 1000 1200 4 Peak adult activity
Many Roundheaded apple tree borer Saperda candida 1514 1798 5 Typical treatment window
Conifer Nantucket tip moth Rhyacionia frustrana 1514 1917 RU Adults 2nd generation
Maple Sugar maple borer Glycobius speciosus 2032 2375 5 Typical treatment window
Locust Locust borer Magacyllene robiniae 2271 2805 5 Typical treatment window
Poplar and Willow Poplar and willow borer Crytorhynchus lapathi 2271 2806 5 Typical treatment window

Click here – “Identifying Clearwing Moth Borers in Pheromone Traps” or “Differentiating the Common Wood Borers of Ash Trees”

SCALE Insect Activity for 1000 – 2500 GDD (~ July)
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Conifer Cryptomeria scale Aspidiotus cryptomeriae 600 800 3 First crawler emergence
Many White prunicola scale Psedaulacaspis prunicola 707 1151 RU Crawlers (1st generation)
Conifer Juniper scale Carulaspis juniperi 707 1260 RU Crawlers (1st generation)
Many Calico scale Eulecanium cerasorum 714 6 Crawlers (1st generation)
Conifer Striped pine scale Toumeyella pini 750 800 4 Egg hatch
Oak, hickory, birch, many Oak leacanium scale Parthenolecanium quercifex 789 6 Crawlers (1st generation)
Acer Cottony maple leaf scale Pulvinaria acericola 802 1265 5 Crawlers (1st generation)
Many, shadetrees Cottony maple scale Pulvinaria innumerabilis 802 1265 RU Crawlers (1st generation) – control target
Oaks Golden oak scale Asterolecanium variolosum 802 1266 5 Egg hatch
Maples Japanese maple scale Lopholeucaspis japonica 829 6 Crawlers (1st generation)
Elm European elm scale Gossyparia spuria 831 1388 6,2 Crawlers (1st generation)
Shade trees European fruit lecanium scale Parthenolecanium corni 932 1645 6,RU Crawlers  – control target
Conifer Pine tortoise scale Toumeyella parvicornis 1000 1200 4 Egg hatch ends, last of crawlers
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 1029 1388 RU Crawlers (1st generation) – control target
Many Indian wax scale Ceroplastes ceriferus 1145 6 Crawlers (1st generation)
Euonymus Euonymus Scale Unaspis euonymil 1150 1388 5 2nd generation targeted treatments
Shade trees European fruit lecanium scale Parthenolecanium corni 1266 1645 5 Crawlers
Conifer Pine Needle Scale Chionaspis pinifoliae 1290 1917 3 Crawlers emerge (2nd generation) – control target
Conifer Hemlock scale Abgrallaspis ithacae 1388 2154 5 Typical treatment window
Malus, Prunus, many Peachtree borer Synanthedon sp. 1500 1800 RU Larvae Treatment
Many White prunicola scale Pseudaulacaspis prunicola 1637 6 Egg hatch / crawler (2nd generation)
Euonymus Euonymus Scale Unaspis euonymil 1700 RU Continued 2nd generation treatments
Conifer Cryptomeria scale Aspidiotus cryptomeriae 1750 2130 RU, 4 Crawlers emerge (2nd generation)
Many Obscure scale Melanaspis obscura 1774 6 Egg hatch / crawler
Conifer Maskell scale lepidosaphes pallia 2035 6 Egg hatch / crawler (2nd generation)
Mainly Tulip Tulip tree scale Toumeyella liriodendri 2037 2629 RU Crawlers (1st generation)
Mainly Magnolia Magnolia scale Neolecanium cornuparvum 2155 2800 RU Crawlers (1st generation)
Maple Japanese maple scale Lopholeucaspis japonica 2508 6 Egg hatch / crawler (2nd generation)
Conifer Elongate hemlock scale Fiorinia externa 2515 2625 RU Typical treatment window – fall activity
Yew, many conifers Fletcher Scale (Yew) Parthenolecanium fletcheri 2515 2800 RU Fall control of overwintering stage

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Native White Birches & Their Resistance to the Bronze Birch Borer

The Dilemma Regarding Birch Trees

Bronze birch borer adult female laying an egg on the bark surface of a birch tree. (Photo Credit: Ohio State Coop. Ext.)

Bronze Birch Borer (Agrilus anxius) adults (440-800 GDD) are now actively searching landscapes for various species of Betula (Birch) to lay eggs upon. The adult beetles will be attracted to susceptible trees that are genetically defenseless or are compromised from stress (e.g., especially drought stress).

It is well known that the native River Birch (Betula nigra) has a strong resistance against the BBB. As a result, this species has been extensively planted in NJ landscapes during the past few decades to the extent of arguably being over-planted. And it is also widely understood that the non-native Asian & European birch species have virtually no or little resistance to the BBB. Therefore, the planting of these non-natives has rightfully been reduced over the decades. However, what about some of our other native species such as the paper, gray, & yellow birches. Is it best to avoid planting these species as well?       

River birch (Betula nigra) is a native birch that is strongly resistant to the bronze birch borer. (Photo Credit: Steven K. Rettke, Rutgers Coop.Ext.)

Is it best to avoid planting other native birch trees in our landscapes, such as the gray birch shown above? (Photo Credit: Steven K. Rettke, Rutgers Coop. Ext.)

 

 

 

 

 

 

 

 

 

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Nursery Pests Scouting June – Bagworms, Scales, Borers, RHFB, BWB


Red-headed flea beetle – Adult emergence beginning any day now

Please refer to this timeline of pest development compiled by Tim Waller in communication with Brain Kunkel (Unv. Del) and Danny Lauderdale (NC State)

  • Contains material selection and timing, along with regime information and considerations

Boxwood Blight Alert – Infection Potential (Saturday) 5/27

Boxwood Blight Risk Assessment as of 5/24/2022
Region Location CODE 24-May 25-May 26-May 27-May 28-May 29-May
Southern Upper Deerfield NJ50 Very Low  Very Low  Low  High Risk Very Low  Very Low 
Central Howell / Freehold NJ10 Very Low  Very Low  Low  Infection Risk Very Low  Very Low 
Northern High Point NJ59 Very Low  Very Low  Very Low  Infection Risk Very Low  Low 
Check local boxwood blight risk here (CLICK HERE – input your area code – select closest weather station – check 7-14 prediction – click on graph / table)

 

Refer to the most recent Alert for more information – CLICK HERE


Pest Scouting – Please refer to these documents for a full listing of insects pests for your area corresponding to growing degree-days (GDDs). 

Contact if seeing insects at different times: twaller@njaes.rutgers.edu (or call the Cumberland County Extension Office – 856-451-2800)

The following key groups of pests will be active, vulnerable, or otherwise treatable during the next month throughout most of NJ. Here, bagworms, scale insects and borers with key life stage events during the 350-1500 GDD timeframe are discussed. Note there are many other insect pests present this time of year so please view the pest scouting guides above for your particular needs.

Projected GDD50 accumulation as of 5/24/2022 (USPEST) Note: Growing degree-day values utilize daily average air temperatures with a minimum temperature threshold (a.k.a. ‘base’) of 50F = GDD50 (max. temp. threshold set at 95F). These values are accumulated from a biofix date, such as January or March 1st in the NE USA. Provided GDD50 are scouting ranges and should be truthed.
Region Location Station 24-May 1-Jun 1-Jul
South Upper Deerfield NJ50 488 638 1358
Central Howell / Freehold NJ10 426 551 1203
North High Point NJ59 288 387 909
Forecast: NOAA NCEP Coupled Forecast System model version 2 (CFSv2) forecast system (3.5 months) (USPEST.ORG)

Refer to this post “Obtaining your local growing degree-days” for additional information 

BAGWORMS (600-900 GDD) (Bagworm hatch prediction as of 5/24/22 – now until July 14 (Southern NJ (NJ50)))
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Conifer mostly, many minor hosts Bagworm Thyridopteryx ephemeraeformis 600 900 RU Larvae (early instars) –

ONLY CONTROL WINDOW

Refer to this post for additional information on Bagworms

BORER Insect Activity for 350 – 1500 GDD (Now until ~July 1 in Southern NJ (NJ50))
Crop type Common Name Scientific Name GDD Min (50F) GDD Max (95F) Reference Developmental / Target Stage
Malus, Prunus, many Lesser peach tree borer Synanthedon pictipes 350 375 4 Adult flight, egg laying
Dogwood, apple, pecan, elm, hickory, willow Dogwood borer Synanthedon scitula 350 850 4 adults, eggs, caterpillars
Birch Bronze Birch Borer Agrilus anxius 440 880 RU Adults (egg laying)
Malus, Prunus, many Peach Tree Borer Synanthedon sp. 500 600 RU Adults – emerge (1st treatment both types)
Rhododendron Rhododendron borer Synanthedon rhododendri 509 696 RU Adults emerge
Malus, Prunus, many Greater peach tree borer Synanthedon exitiosa 575 710 4 Adult emergence
Many Roundheaded appletree borer Saperda candida 802 1129 RU Adults
Ash Emerald ash borer Agrilus planipennis 1000 1200 4 Peak adult activity
Malus, Prunus, many Peachtree borer Synanthedon sp. 1500 1800 RU Larvae Treatment
Many Roundheaded apple tree borer Saperda candida 1514 1798 5 Typical treatment window
Conifer Nantucket tip moth Rhyacionia frustrana 1514 1917 RU Adults 2nd generation

Click here – “Identifying Clearwing Moth Borers in Pheromone Traps” or “Differentiating the Common Wood Borers of Ash Trees”

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