Pest of the Week - Asian Tiger Mosquito

Asian Tiger Mosquito - University of California, Riverside

The tiger mosquito is native to Asia. It is believed the species spread to the United States as a result of the international trade in used tires. The United States imports millions of tires from Asia due to the high rubber content of Asian tries, for remanufacturing purposes. Tiger mosquitoes were originally closely associated with used tires, which are used as sites for egg deposition and larval development. Tires that were imported to Texas from Asia during 1980s brought tiger mosquitoes to the United States. The trade of used tires within the U. S. has helped to dispersed the mosquito throughout the eastern and midwestern states.

Natural History

Adults of this mosquito have black bodies with conspicuous white stripes. A distinctive single white stripe runs the length of the back. Body length is approximately 0.5 centimeter. Distinct silver-white bands are evident on the palpus and tarsi. Eggs are approximately 0.1 centimeter in length and dark brown to black. Eggs are laid in moist areas just above the water surface and are capable of overwintering. Eggs hatch upon inundation and immature stages (larvae and pupae) of the life cycle occur in water and it only needs 1/4 inch depth to complete its life cycle.  Larvae are filter feeders and occur in standing water found in discarded tires, small containers and tree holes. Pupae are comma-shaped and dark brown in color.

Adult tiger mosquitoes live from a few days to several weeks, largely depending on weather conditions. Hot, dry weather reduces life expectancy. Regardless of life span, adult tiger mosquitoes seldom move far from the containers in which they were born. Most adults will be found within a few hundred yards of the breeding container.

Asian Tiger Mosquitos feed day and night, especially early in the morning and late afternoon. Male mosquitos, as well as very young mosquitos, are vegetarian and eat plant matter. Female mosquitos drink blood from humans, domestic and wildmammals, reptiles, amphibians, and birds.

Management Strategies

Management of adult populations is more complicated than for other mosquito species due to insecticide tolerance to a variety of insecticides.  Eliminating breeding habitats can be an effective method to control mosquitoes.  Empty or eliminate places that may contain standing water for more than a week.  Additionally you should:

• Screen or cover rain barrels
• Clean overgrown ponds and stock with fish
• Clean leaf-clogged gutters
• Throw away or destroy used tires
• Fill tree holes
• Change water in birdbaths weekly
• Empty water from flower pot dishes
• Recycle old bottles and cans

If you must be out and about, here are some tips for avoiding mosquito bites:

1. Avoid areas of high mosquito infestation.
2. Avoid unnecessary outdoor activities at dawn and dusk when mosquitoes are most active.
3. Wear long pants, long-sleeve shirt and hat when outdoors.
4. Use mosquito repellents containing DEET. Consult a physician before applying DEET to young children.
5. Restrict the outdoor play of your children if mosquitoes are present.
6. Drain all water-holding outdoor containers around the home.
7. Inspect basements and crawl spaces. If they are flooded, drain as quickly as possible.
8. The very young, the elderly and persons with depressed immune systems are at most risk for acquiring disease from mosquito bites.

Additional Information

Featured Creatures: Asian Tiger Mosquito - University of Florida

New Jersey Statewide Adult Mosquito Surveillance Reports - Rutgers University

Asian Tiger Moquito in New Jersey

Mosquito Control - Burlington County Health Department

State of Maryland Mosquito Control Home 

IPM Notes for July 25, 2013

Pheromone Trap Results
Trap #1 - Black Cutworm
2 moths – Black cutworm, 7 chaffer beetles, 1 bee, 1 lightning bug

Trap #2 - Corn Ear Worm
1 Corn Ear Worm moth, 9 noctuid moths, 1 chaffer beetle

Trap #3 - European Corn Borer
Inactive

Trap #4 - Fall Army Worm
1 chaffer beetle, 3 ground beetles, 1 undetermined beetle (due to deterioration), 1 mosquito 


Helios Trap
Inactive

Field Corn
In the field corn, we looked at an example of plant growth when reaching for sunlight. We looked at a velvet leaf plant that was nearly 6 feet tall and mostly stalk. Leaves were few and far apart. It is a very different growth pattern from velvet leaf plants on the edge of the field.

We looked at the milk line on the kernel. At this time it is clearly visible. The kernel is wet when crushed, but will change to a doughy starch when the corn is ready for harvest.
This field corn variety has the end of the ear exposed when the silks fall away. This makes it susceptible to many pests and conditions including, bugs, worms, moisture, fungus.
There is a disease beginning to show on the stalks. If this progresses sufficiently the stalks will become weak and may break in wind or heavy downpour conditions.

Popcorn
Noted some leaf damage but could not locate an agent. Popcorn is at a stage where the whorl is open to environmental and insect impact.

Note: Erosion after the 4” rain received has reached depths of 4 – 8 inches with clear gullies and rills. Some plants are having sediment buildup above the roots, while others are having soil taken from the root system leaving roots exposed.

Wheat/Soybeans
This field is at stage V2 or the 2nd trifoliate stage. The root system is strong but no nodule formation yet. Soybeans are sensitive to the length of the day, so it is a race to see if the plants will fully develop and fruit before the lack of daylight shuts the plants down.

Sweet Corn
All varieties are tasseled, but there is little silk showing. The tassels have not started shedding pollen, so there is still some time. Most of the varieties are putting down brace roots.

Hay Field
The hay has been cut down and is drying. 2nd cutting is considered to be a good hay for its smoothness in the mouths of the feed animals.

Soybeans
These soybeans are now classified as being in the reproductive stage and would have an R-number instead of a V-number (see above). They are setting bean pods and still blooming. There is evidence of leaf hoppers (from the cut hay field) and thrips (leaf curling).

Demonstration Gardens

• Peanuts - Plants were showing signs of needing calcium and potassium. Calcium was added without incident. Potassium was applied at the recommended rate but still burned the leaves. Plants are recovering and showing growth with the added nutrients. The plants should have more flowers but may be being affected by the lack of heat. There is not much evidence of pegging from existing flowers.

• Peppers are recovering nicely. 

• Tomatoes – next thing to watch for will be late blight.

Thanks to Roger for compiling this week's notes.

 

Late Blight Update

There is an update from Rutgers Cooperative Extension Plant and Pest Advisory regarding late blight.  Late blight is a fungus-like disease caused by the pathogen Phytophthora infestans that mainly attacks tomatoes and potatoes.  Late blight was one of the factors that contributed to the Irish Potato Famine.

For more information on the late blight update, visit the Plant and Pest Advisory link.

Link:  Plant and Pest Advisory - Late Blight Update  
 

IPM Notes from July 18, 2013

Pheromone Trap Results
Trap #1 - Black Cutworm
1 ladybug, 1 juvenile green stinkbug, 1 Japanese beetle, 3 European Chaffer beetles, 4 click beetles, 1 cucumber beetle.
Trap #2 - Corn Earworm
1 ladybug, 1 corn earworm moth, 2 unknown beetles
Trap #3 - European Corn Borer
Inactive
Trap #4 - Fall Army Worm
1 cereal leaf beetle, 1 corn borer moth

Helios Trap
Inactive



Field Corn Field
Firing on lower leaves is still present – lack of nitrogen – and moving to higher leaves.
Tassels are breaking – no insects so it may be a weakness in the variety.

We looked at one ear. It is full, all kernels are formed and it has good size. Next week we will learn to calculate the expected yield from the number of kernels and rows.

Popcorn Field
Areas where there was standing water are now crusting. This would be a problem for germinating seeds, but not for growing plants. Buggy whipping is still present on a significant percentage of plants. There will be stunting of plant growth. It is also very visible the difference in plant height between those plants that were water stressed and those that were not. We will now need to watch for moths coming over from other fields. 

We looked at signs of erosion – rilling and gullying. We talked about ways that farmers use to combat erosion. Unless there are continued heavy rains and runoff, this will not be a problem in this field.

Wheat Field now a Soybean Field
Soybeans are up and at the unileaf stage also called mid group 3 stage. It will be a race to see if we get full maturity and what kind of yield by October.

Hay Field
Not yet harvested for 2nd cutting.

Sweet Corn Field
Some varieties have begun to show tassels, but not showing ears. Because all the varieties were planted at the same time in close proximity there will be some cross-pollination. Because of all the moisture at the beginning, the roots of this crop have not grown deep. During these last days of hot, dry weather they are now showing the leaf curling signs of drought stress. They may need to be irrigated. Rule of Thumb for sweet corn; tassels and silks = 21 days.

Soybean Field
Soybeans are flowering and setting on bean pods. There are leaf hoppers present, possibly thrips (though we did not find any). We also found a green ‘clover’ worm or ‘inch’ type worm.

In the demonstration plots:

• Peanuts are beginning to peg.
• Hops can be harvested.

Community gardens
Green bean yellowing possibly from potassium deficiency.

Weeds reviewed

• Ragweed
• Barnyard grass
• Foxtail
• Velvet leaf
• Jimson weed
• Yellow nut sedge
• Goose grass

Special thanks to Roger for compiling this week's note and to Ramona for the photos.

IPM Notes for July 11, 2013

Pheromone Trap Results
Trap #1 – Black Cutworm
5 click beetles, 1 corn earwig, 12 European Chaffer beetles, 3 lady bugs, 4 chaffer-related beetles.

Trap #2 – Corn Ear Worm
2 European Chaffer beetles, 2 click beetles, 3 lady bugs, 6 juvenile moths (not corn ear worm)

Trap #3 – European Corn Borer
Pheromone has been removed due to high attraction for bumble bees. Trap still contained many bumblebees.

Trap #4 – Fall Army Worm
2 Alfalfa Weevil, 1 Lightning bug, 1 click beetle

Helios Trap
The corn has overtopped the trap, so no analysis done.



Corn Field
The corn is in the ‘Tassel’ stage. Also, we are seeing the development of the ‘brace’ roots or adventitious roots. Many of the tassels are not only out, but the pollen is out also. However, many of the ears have not yet put out their silk. This will mean undeveloped ears. This is possibly due to the stresses of the rain and low nitrogen. Because of the rain and wet conditions leaf spot is now developing. 

Brace roots in corn field

Popcorn Field
Buggy whipping is occurring in the popcorn – perhaps as much as 10%. This can be from herbicide damage, flea beetle (no evidence), and environmental causes. Most likely it is from late germination with twisting in the ground before emergence.  We are noting the growth of algae on the top of the ground due to the wet weather and presence of standing water in the fields.

Buggy whipping

Algae in popcorn field

Sweet Corn Field
Noted areas of stunting due to wet conditions. Noted presence of ‘suckers’ (extra stalk coming up from the root). Noted nitrogen deficiency with some evidence of ‘firing’ on the lower leaves.

Wheat Field
Wheat has been harvested. Field has been replanted with soybeans. Straw was not harvested. Due to the wet weather, harvesting and planting was delayed by approximately 6 days from the optimal. This may mean a 6% loss in yield at harvest. (1% per day after optimal planting day)

Soybean Field
Herbicide applied – particularly for horsetail (Equisetum species). Soybeans are flowering. There is a stem and leaf disease developing.

Hay Field
Behind time for the 2nd cutting. (time is determined by alfalfa bloom @ 10%) Need 3 good drying days.



Demonstration Gardens

• Peppers are still water-stressed. Seeing fungal/mushroom growth from the woodchip mulch.

• Tomatoes are showing leaf curl with the presence of lace wings, thrips, and leaf hoppers. Tomato harvest is expected to be much lowered by the wet weather this season.

• Peanuts are still blooming but are not pegging. This is possibly due to the wetness and possibly to a calcium deficiency.

• Cowpeas look great.

• Buckwheat was planted too thickly. Stems were spindly and long and the center of the plot has been laid over by the wind.

• Blueberries – 2 plants are showing Scorch or Fire Blight.

• Hops cones are ready for harvest.

Community Garden Plots
Evidence that powdery mildew has begun.

Other Notes
Bill noted that he is receiving reports from farmers that potatoes are rotting in the ground.


Thank you Roger for compiling this weeks notes.

Pest of the Week - Leafhopper

A leafhopper, Graphocephala sp. (Homoptera: Cicadellidae). Photo by C. L. Barr.

Natural History

Leafhoppers are insects belonging to the family Cicadellidae in the order Hemiptera.  They are recognized by their piercing-sucking mouthparts and by the presence of rows of spine-like setae (hairs) in their hind tibiae.

Leafhoppers go through incomplete metamorphosis in their development. Female leafhoppers insert tiny eggs in tender plant tissue, causing pimplelike injuries.  Overwintered eggs begin to hatch in mid-April. Wingless nymphs emerge and molt four or five times before maturing in about 2 to 7 weeks.  Nymphs resemble adults except that they lack wings; later-stage nymphs have small wing pads.  Leafhoppers overwinter in the Gulf States and migrate north each year.  They usually arrive in New Jersey in June.  There are two to three generations per year in New Jersey.

Leafhopper feeding causes leaves to appear stippled, pale, or brown, and shoots may curl and die. Some species cause a diamond-shape yellowing from the leaf tip. A few species secrete honeydew on which foliage-blackening sooty mold grows. Black spots of excrement and cast skins may be present on leaves and/or fruit. Some leafhopper species transmit plant diseases, but this is troublesome mostly among herbaceous crop plants. 

Potato Leafhooper Empoasca fabae Life Cycle - University of Kentucky

Potato leafhopper, Empoasca fabae, causes hopper burn on red maple and other important shade trees and shrubs. 

 
Leafhoppers can carry the bacterium, Xylella fastidiosa, which causes bacterial leaf scorch in elms, oaks, maples, and sycamores. Leafhoppesrs can also carry a phytoplasma which causes the disease known yellows, ash yellows affects ash, and elm yellows affects elms. Aster yellows affects coneflower, Echinacea. Aster yellows is spread from plant to plant by the leafhopper, Macrosteles phytoplasma. Once infected, diseased plants should be promptly removed and discarded to reduce further spread.

Managment Strategies

On maple, look for leafhoppers on the leaf underside. Look for stippling of leaves and curled or stunted shoot tips. Inspect trees regularly looking for leafhoppers feeding on the lower surface of leaves. Look also for distorted or stunted growth and yellow leaves.
 
Remove plants exhibiting the scorch-like symptoms or the distorted and stunted growth of aster yellows.

Avoid over fertilization, which may cause populations of leafhoppers to increase. ‘Autumn Blaze’, a hybrid of silver and red maple, is highly resistant.

Spray where needed, concentrating on regions where leafhoppers prefer to feed, particularly on new growth.

Bigeyed bugs, damsel bugs, assassin bugs and lacewings are common predators of leafhoppers.

Precautionary Statement on Pesticide Use

All pesticides have both benefits and risks. Benefits can be maximized and risks minimized by reading and following the labeling. Pay close attention to the directions for use and the precautionary statements. The information on pesticide labels contains both instructions and limitations. Pesticide labels are legal documents, and it is a violation of both federal and state laws to use a pesticide inconsistent with its labeling.  Always read and follow the label.



Additional Information

Leafhoppers Fact Sheet 237 - NJAES - Rutgers University

Leafhopper - Department of Entomology - Texas A&M University

Potato Leafhopper on alfalfa - Penn State University

Virginia Alfalfa IPM Source - Virginia Tech