Friday, May 31, 2019

Welcome to Mosquito Season

With the unofficial start of summer, now is a good time to start planning to reduce the number of mosquitoes around your home. Worldwide there are approximately 3500 species of mosquitoes.  They live in almost every region of the earth from subarctic to the tropics. As of 2015,  63 species of mosquitoes were found in New Jersey.  Mosquitoes are members of the order Diptera.  The word Diptera comes from the Greek di which means two and ptera which means wing.  The order Diptera also includes the common housefly.

Like other true flies, mosquitoes undergo a complete metamorphosis: egg, larva, pupa and adult.  The larvae are anatomically different than the adult mosquito, it lives in a different habit and feeds on different nutrients.  The pupa is a non-feeding stage.
Mosquito life cycle - Knox County Tennessee
Mosquito larvae are uniquely adapted for aquatic life.  They need oxygen for respiration and water-borne particles for food.  The larva feed on micro-organisms and organic material in the water where they breed.

Mosquito Larvae Videos from the University of New Hampshire - Center of Freshwater Biology
Both the male and female mosquito get their protein from nectar.  The female mosquito feeds on blood to obtain the nutrients she needs to produce eggs.  The reaction to the saliva that the female mosquito injects when feeding is what causes itching.  Depending on the species a female mosquito may lay between 50-500 eggs.

The illustration below from a CDC(Centers for Disease Control and Prevention) manual shows three of the most common mosquito genera and some of their chief characteristics.

ANOPHELES AEDES CULEX






This interesting photograph shows the proboscis of a mosquito.  The proboscis is the mouth part of the female mosquito that is used for sucking blood.

Mosquito proboscis - Copyright © 2015 Choo, Buss, Tan and Leal. Creative Commons Attribution License (CC BY). Front Physiol. 2015; 6: 306. Published online 2015 Oct 29. doi: 10.31389/fphys.2015.00306



Sometime insects like the one pictured below are mistaken for mosquitoes.  The easiest way to tell the difference between a crane fly and a mosquito is by observing the mouth parts.  

Crane fly - notice the missing proboscis - Texas A&&M AgriLife Extension
Control

Water is necessary for mosquito development.  By eliminating sources of standing water, the number of mosquitoes will be reduced.  Listed below are some of the common methods that you and your neighbors can use to reduce the sources of standing water and control the mosquito population in your neighborhood.
  • Remove old tires or drill holes in those used for playground equipment to allow them to drain. 
  • Check boats for holding water, clear drain holes, turn over, cover or increase angle to aid drainage.
  • Check tarps on boats or other equipment/items that may collect water in pockets or indentations.
  • Remove vegetation or obstructions in drainage ditches that prevent the flow of water.
  • Pick up broken, unused or discarded toys that hold water.
  • Pick up all beverage containers and cups.
  • Replace water in birdbaths once a week.
  • Replace water in pet and other animal feeding dishes or troughs at least once a week.
  • Fill tree holes (hardwood trees) that hold water with spray, insulating foam sealant.
  • Position garbage cans and lids so they don’t hold water.
  • Change water in planters, including hanging plants, at least once a week.
  • Maintain gutters so water drains properly.
  • Monitor all types of drainage pipes/systems for standing water.
  • Fix dripping outdoor faucets that create pools of water.

Female mosquitoes find a host by using a combination cues like CO2,  vision and thermal sensory information to detect body heat.  Mosquito repellents are used to block a female mosquito's ability to detect a host.  Listed below is a table the summarizes the effectiveness of various mosquito repellents.

Table 1. Summary of effectiveness of mosquito repellents reported by Fradin, M. S. and J. F. Day. 2002. Comparative efficacy of insect repellents against mosquito bites.  New England Journal of Medicine 347: 13 – 18.
Product1Active IngredientMinutes of Complete
Protection
Evaluation2
Off! Deep Woods23.8% Deet302A
Sawyer Controlled Release20% Deet234B
Off! Skintastic6.7% Deet112C
Bite Blocker for Kids2% Soy oil95D
Skin-So-Soft Bug Guard Plus7.5% IR353523E
Natrapel10% citronella20E
Herbal Armor12% citronella
2.5% peppermint oil
2% cedar oil
1% lemongrass oil
0.05% geranium oil
19E
Green Ban for People10% citronella
2% peppermint oil
14E
Buzz Away5% citronella14E
Skin-So-Soft Bug Guard0.1% citronella10E
Skin-So-Soft Moisturizing Sun Care0.05% citronella3F
Gone Original Wristband9.5% Deet0.3G
Repello Wristbande9.5% Deet0.2H
Gone Plus Repelling Wristband25% citronella0.2H
1May or may not be available for purchase or registered for use in New Jersey.
2Letters indicate groups of repellents that are statistically similar; e.g., the six repellents in category E are statistically similar to each other.

By eliminating the larval habitats on your property and taking a few simple precautions, you can reduce the threat of mosquito-borne illness and annoyance in and around your home and neighborhood.


Additional Information

Bti for Mosquito Control - US Environmental Protection Agency

Crane flies, not mosquitoes - Texas A&M AgriLife Extension

Macroinvertebrate Resources - Stroud Center Water Resources

The American Mosquito Control Association

The Asian Tiger Mosquito - Center for Vector Biology - Rutgers University

Burlington County Mosquito Control Division


References
Anonymous, 1967. CDC Manual. Pictorial Keys. Arthropods, Reptiles, Birds and Mammals of Public Health Significance. US/HEW, Public Health Service. 192 pp.


Friday, May 17, 2019

Deadnettle and Henbit. What's the difference?

Deadnettle or purple deadnettle and henbit are often mistaken for each other.  Once you know what to look for they are easy to differentiate.  First some background.  In some of the literature you will see these plants referred to as purple deadnettle(Lamium purpureum) and henbit deadnettle (Lamium amplexicaule).  Unlike some other nettles, deadnettles do not sting.  In other words it is a "dead" nettle.  The common name henbit comes from observations that chickens like to eat it.

Deadnettle and henbit are winter annuals.  Both plants germinate in the fall and resume growth in the spring as the temperature rises, they set seed and then die in the late spring or early summer.


Purple deadnettle and henbit are members of the Laminaceae (also Labiatae) mint family.  Purple deadnettle (on the left) and henbit (on the right) have square stems which are a common identification characteristic of members of the mint family.

Henbit - Photo by Dr. John Meade, weed scientist emeritus
Rutgers NJAES Cooperative Extension

Henbit (Lamium amplexicaule)
Lamium amplexicaule L. - henbit deadnettle - Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York. Vol. 3: 121. Provided by Kentucky Native Plant Society. Scanned By Omnitek Inc.- USDA Image Library
Henbit has petioles on the lower leaves but not the upper leaves.  The upper leaves are clasping, hence the species name amplexicaule which means clasping.

Deadnettle - Photo by Dr. John Meade, weed scientist emeritus
Rutgers NJAES Cooperative Extension

Deadnettle (Lamium purpureum)
Lamium purpurem L. - purple deadnettle - Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York. Vol. 3: 121. Provided by Kentucky Native Plant Society. Scanned By Omnitek Inc. - USDA Imahe Library
The leaves on deadnettle all have petioles.  The length of the petioles tend to get smaller as you move upward on the plant.


Deadnettle (on the right)  and Henbit (on the left) Leaves
Notice that the leaves on the deadnettle are more triangular in shape and not as deeply lobed as the leaves on the henbit.  The leaves of henbit have a more rounded shape, are deeply veined and have hairs on the upper and lower surfaces.

Visit the weed control links listed below for information on controlling these weeds around the home or in the lawn.

NOTE: Always read and follow herbicide directions carefully. Do not use herbicides for controlling broadleaf weeds in turf such as dandelion in or near ornamental planting beds. If weeds are a persistent problem in landscape planting beds homeowners may wish to consult with a professional landscape contractor. 

Additional Information

New Jersey Weed Gallery - Rutgers NJAES Cooperative Extension

Weed Control in Home Lawns - Rutgers NJAES Cooperative Extension

Weed Control around the Home Grounds - Rutgers Cooperative Extension



Sunday, March 3, 2019

Asian Longhorned Tick - A New Invasive Species

There is a new invasive species in New Jersey: the longhorned tick (Haemaphysalis longicornis).  The longhorned tick is a member of the family Ixodidae which means that it is a hard tick.  Hard ticks have three distinct life stages.  Depending on the temperature, the tick's eggs usually hatch between 60-90 days.  When the larva emerge from the eggs they have three sets of legs.  After having a blood meal they molt and become nymphs and acquire four sets of legs.  Nymphs feed for approximately 7 days and detach.  The nymph then spends about 40 days living under the vegetation before molting and becoming an adult which also has four sets of legs.
Larva (Source: lucidcentral.org)
Nymph (Source: lucidcentral.org)
Male (Source: lucidcentral.org)
The longhorned tick finds a host using a behavior called "questing".  A questing tick crawls up the stems of grass or perches on the edge of leaves.  When the tick detects a host it uses its extended front legs to attach itself to the host.
Questing Tick
Credit: Graham J. Hickling, The University of Tennessee. Public domain.

After having fed on a host for about seven days, the female detaches itself and begins searching for a suitable place to lay eggs.  Within 1-2 weeks the female tick will lay around 2,000 eggs during a 2-3 week period.  Because the longhorned tick is a parthenogenesis species, it can reproduce asexually.  The female does not require a male tick to reproduce.

While the longhorned tick is new to New Jersey it has been a pest in New Zealand for decades. In New Zealand the tick has been found on the following animals.

Mammals
  • Brushtail possum (Trichosurus vulpecula),
  • Cat (Felis domesticus),
  • Cattle (Bos taurus),
  • Dog (Canis familiaris),
  • Donkey (Equus asinus),
  • Goat (Capra hircus),
  • Horse (Equus caballus),
  • House mouse (Mus musculus),
  • Pig (Sus scrofa),
  • Rabbit (Lepus cuniculus),
  • Sheep (Ovis aries)
Birds
  • Dosmestic duck (Anas boscas var),
  • Domestic fowl (Gallus gallus),
  • House sparrow (Passer domesticus),
  • Kiwi, Pheasant (Phasianus colchicus),
  • Skylark (Alauda arvensis),
  • Thrush (Turdus philomelus),
  • Turkey (Meleagris gallipavo)
Prevention
Most tick bites can be prevented.   Some of the simple things you can do to prevent exposure to ticks are:


  • Avoid areas bushy and grassy areas where ticks normally live.
  • Wear light colored clothing which makes it easier to identify ticks.
  • Wear clothing and boots that have been treated products containing 0.5% permethrin.
  • Use Environmental Protection Agency (EPA) registered insect repellants.
  • Walk in the center of trails.
  • Check you clothing and body for ticks after you have been outside.
  • Shower soon after you have been outdoors.


Tick Removal
Removing a tick isn't difficult.  Here are the simple steps for removing a tick:


  1. Use a pointed tick removal tweezer
  2. Disinfect the area with rubbing alcohol
  3. Grab tick close to skin and use slow, steady motion to pull tick out
  4. Disinfect the area again
  5. Consider Tick Testing for infection

Here is a short video that demonstrates the proper method for removing a tick.



Identification
If you find a tick you can bring it to the Rutgers Cooperative Extension office located at 2 Academy Dr, Westampton, NJ 08060 for identification. Ticks should be placed in a sealed plastic bag or a container with a small piece of moist paper towel to prevent dehydration.



Additional Information

Tick Bites Prevention - Centers for Disease Control and Prevention

How to Recognize a Longhorned Tick - Center for Vector Biology, Rutgers University

Tick Biology - UC Davis, Department of Entomology and Nematology

TickEncounter Resource Center - University of Rhode Island

Zoogeography of the New Zealand Tick Fauna - University of Wellington, New Zealand



Tuesday, July 24, 2018

Spiderwort


The genus name honors John Tradescant (1570-1638) and his son John Tradescant (1608-1662), botanists and successive gardeners to Charles I of England.

Spiderwort (Tradescantia virginiana) is native wildflower.  A herbaceous plant that grows up to three feet tall.  Noted for its three-petaled violet-blue flowers with six contrasting yellow stamens which grow in terminal clusters.  The flowers open a few at a time and for only one day.  The root system is thick, fleshy, and fibrous, sending off occasional offshoots nearby. Spidewort thrives in thickets, meadows, roadsides and woodland borders.


While the flowers are beautiful, spiderwort can take over a flower bed.  Spiderwort is difficult control because of its large root crown which provides energy for regrowth.  In small areas and hand removal is the best method of control.

Tradescantia virginiana


Additional Information

Tradescantia virginiana - Missouri Botanical Garden

Virginia Spiderwort -USDA Nation Resources Conservation Service

The Collectors: Tradescants

Spiderwort spreading and could become a hay field pest - University of Florida


Wednesday, June 6, 2018

New Pest on the Rise - Spotted Lanterfly

The Spotted Lanternfly, Lycorma delicatula (White) is neither fly nor a month. The Spotted Lanternfly is a native insect of China, India and Vietnam and an invasive planthopper.  At first, the spotted lanterfly had only been found in Berks County, Pennsylvania.  Recently, individuals have been found in Virginia, New York and Delaware.

The spotted lanternfly has been reported from over 70 species of plants, including the following:
  • Tree of heaven (Ailanthus altissima) (preferred host)
  • Apple (Malus spp.)
  • Plum, cherry, peach, apricot (Prunus spp.)
  • Grape (Vitis spp.)
  • Pine (Pinus spp.
Adults are 1 inch long and ½ inch wide at rest. The forewing is gray with black spots of varying sizes and the wing tips have black spots outlined in gray. Hind wings have contrasting patches of red and black with a white band. The legs and head are black, and the abdomen is yellow with black bands. Early immature stages are black with white spots. By the last immature stage they develop red patches in addition to the black color with white spots. This is the last immature stage before they mature into an adult.  Immature insect and adults are visually striking when the bright red of the hind wings is exposed.

Photo courtesy of Lawrence Beringer, Pennsylvania Department of Agriculture
Adult Spotted Lanternfly (bugwood.org)
Adults feed by puncturing the plant tissue to feed on sap.  The feeding damage can cause sap to run down the surface of the plant and encourages the growth of sooty mold which leaves dark streaks on the trunks of trees.
If you think you have seen or collected a Spotted Lanternfly please report it to the New Jersey Department of Agriculture and the Department of Entomology at the Rutgers School of Environmental and Biological Sciences by emailing slanternfly@njaes.rutgers.edu.

Additional Information

Spotted Lanterfly - New Jersey Agricultural Experiment Station

Spotted Lanterfly - Pennsylvania Department of Agriculture

Tree of Heaven - Invasive Exotic Plants of the Southeast - NC State University