“WHAT’S HAPPENING?”
The University of Tennessee/Agricultural Extension
Service
Entomology
& Plant Pathology - EPP #60
June
2, 2006
Potato leafhoppers are tiny light-green leafhoppers that
suck sap from the veins on the underside of leaves of alfalfa, potato, rhubarb,
dahlia, eggplant, and red maple. Its
feeding on the phloem cells causes them to become torn, distorted and the xylem
tubes plugged. The leaf tips turn brown
or the entire brown margin of the leaf can become brittle and curl inward or
upward depending on the plant. This hopperburn often appears like a rapidly occurring drought
stress. The potato leafhoppers are
wedge-shaped and only 1/8 inch long. The
adults can fly and they overwinter further south in
the Gulf Coast States. In the early
spring they migrate north with spring storms and can be found in high numbers
on crops such as alfalfa or in red maple trees.
Eggs are laid on the host plants where the nymphs develop to
adulthood. In the past week or so, many
of the resulting adults have been seen attracted to outdoor lights. The hopperburn on
the new growth of red maples has also increased tremendously in the past couple
weeks. A couple of sprays made over the
last month would have prevented most of the hopperburn. If a new flush of growth is seen later in the
spring or summer due to good growing conditions, treat with Sevin, Dursban, Talstar, Tempo,
Decathlon, Tempo SC Ultra, Scimitar, Discus, Marathon, Merit, Flagship, or Tristar.
GROUND-NESTING “NATIVE” BEES NOT HARMFUL
by
John Skinner and Karen Vail
I wrote a similar article a couple years ago. This year I’ve
received a dozen calls from homeowners and pest control operators concerning native
bees that were nesting in the ground near homes and gardens.
Most people were concerned that these bees
were a stinging threat, especially for those callers that have young
children. These bees are not a stinging threat,
they are beneficial as pollinators of flowering
plants in the garden or landscape.
Make sure the “bees” are bees and not something else. I
would be concerned if the suspect “bees” are indeed yellowjacket
wasps (see UT SP341-M for details including identification characteristics http://www.utextension.utk.edu/publications/spfiles/sp341m.pdf.
The yellowjackets are a stinging threat. Yellowjackets often nest in the ground but
there are seldom more than two entrances to the nest.
Yellowjacket coloration usually combines alternating bright yellow and black bands while many ground nesting
bees are grey or black (see below). A few sweat bees are bright metallic green-blue.
There are hundreds of species of ground nesting bees in
Tennessee. They range in total body
length from 5mm (ca. 3/16") [small sweat bees] to honey bee size of 11mm
(ca.7/16") to larger digger bees at 19mm (ca. 3/4"). They are usually
black with grey hairs but some can be metallic green or blue. These bees range in
sociality from being solitary (each single female works alone) like many leaf cutter bees [Megachilidae],
mining bees [Andrenidae], and digger bees [Anthophoridae] to primitively eusocial as with some sweat bees [Halictidae](workers
help care for brood, progressive feeding, and or overlapping generations).
I will include some details about the families of bees
involved below, however, none of these bees are a
threat to safety regarding stinging. You
would have to capture a female in your hand and squeeze it to make it sting or
very rarely a female bee could get trapped inside clothing and sting when the
cloth restricted its movement. These bees often make numerous nests close together in the ground, especially when
they find soft, loose soil that is easy to dig in. Hundreds of bees may be observed flying in
and out of the nest area close to the ground.
Often the bee that flies up to “check you out” is a male and it will
soon determine that you are not a female bee and fly away.
Homeowners see numerous flying bees and panic, thinking
that they could be stung or that a child playing in the yard is at risk.
There is no need to control them with chemicals or other methods. My advise
is to leave them alone, because they are not harmful and do a great job pollinating any flowering plant in the vicinity.
I would not have children playing on top of the nesting site because a bee may accidentally fly up into their clothing.
The area could be fenced off with wood stakes and engineers flagging to mark the nesting site and make it easy to avoid.
Halictidae (sweat bees) These bees are tiny (5mm) to small in size (9mm) and usually
nest in the ground. Some are metallic blue or green and all females are excellent pollinators.
Megachilidae (leaf-cutter bees)
Some leaf-cutters actually nest in the ground in large groups and they are called
mason bees because they plug cells and entrances to the nest with mud and not
with pieces of leaf. The females have a dense patch of longer hair on their abdomens
that they put pollen into.
This patch may appear to be bright yellow due to the color of pollen they have collected.
Their size ranges from small (7mm) to medium (12mm) and sometimes large (19mm).
Andrenidae (mining bees)
These bees have been particularly abundant this spring.
Mining bees nest in loose soil and most are solid black,
especially the abdomens and are covered with
fine gray hair. They (females) store pollen in the longer
hairs on their hind legs. Males have conspicuously longer
antennae then females.
Anthophoridae
(digger bees)
Digger bees nest in the ground and some make an elaborate outer turret (tunnel) of mud that
encases the entrance to the borrow. These bees are
medium (11mm) to large (18mm) in size. They carry pollen on long hairs on the
hind legs and are dark in body color and may have gray or brown hairs that give
them a reddish hue.
Most of the sites of ground nesting bees we have examined
where made by mining bees or digger bees and posed no hazard to the landowner.
Many people became enthralled and really enjoyed watching the bees when they
learned that there was no risk involved..
Avoid exposure from absorption by wearing the personal
protective equipment, PPE, listed on the label.
Launder your clothing often. Keep safety equipment clean and in good working order.
Wash your hands before going to the bathroom.
Avoid exposure from inhalation by using the proper
respirator. Be sure the respirator fits
and all safety equipment is functioning correctly.
Avoid exposure from ingestion by washing your hands before eating, drinking or smoking. Store pesticides separately from any edibles.
Pesticides are toxic by nature. They are made to kill living organisms. Toxicity is the innate capacity or ability of a chemical to be poisonous or harmful at some level. It is expressed in LD50, which is the lethal dose it takes to kill 50% of a test population of animals.
Acute toxicity is a rapid response within minutes or hours
(usually within 24 hours, to a single exposure or dose of the chemical. Usually a person experiences nausea,
vomiting, headache, blurred vision etc. Symptoms similar to the flu.
Chronic toxicity results from repeated exposures over a
long time to doses of chemicals, resulting with body damage. A few examples of chronic toxicity are:
•
Liver or
kidney damage
•
Nervous
system damage
•
Respiratory
damage
•
Reproductive
problems
Some pesticides are slightly toxic. Others are moderately and highly toxic. But, no matter how toxic the chemical you are
using, always protect yourself with at least the personal protective equipment,
PPE, listed on the label. If you get any
on your skin, wash it off immediately.
If you are inhaling it, get to fresh air. And, avoid any type of ingestion of
pesticides. Wash your hands before
eating, drinking, smoking or going to the bathroom after using pesticides.
EDEN PLANT BIOSECURITY COURSE, 2006
EDITION
by Darrell Hensley
EDEN has a new edition of a biosecurity
course which provides updated and timely resources preventative activities and current response
efforts for Soybean Rust. Extension professionals play a vital role in
plant and crop biosecurity education. An EDEN survey showed that 80 percent of
agricultural and horticultural producers would first turn to
Extension if they suspected something
abnormal in their crops. This course was designed for Extension professionals
who understand the urgency of plant protection and will have the opportunity to teach plant biosecurity management to those involved in the U.S. agricultural sector. By taking this
course, Extension professionals in your
state will be equipped to teach others at the
community level how to prepare for, respond to, and recover from a
plant biosecurity
event, as well as how to reduce the effects of future plant biosecurity events.
As it is an interactive, online course, it provides a user with ready-to-use presentations,
applied activities, and handouts for
producer workshops and/or community awareness presentations. The course is available on the EDEN Web site
at
http://www.eden.lsu.edu/LearningOps/PlantBio/.
ASSAIL 70WP & ASSAIL 30 SG
INSECTICIDES
by Gene Burgess
Cerexagri has received labels for Assial
70 WP and Assail 70 WP for aphid control on tobacco. They also have ovicidal
activity on budworms.
They are nicotinoids and slightly toxic with
the signal word CAUTION. They are
generally non-toxic to aquatic organisms, but, toxic to bees.
Aphids
Assail
70WP 0.6-1.7 oz. / A
Assail
30SG 1.5-4.0 oz. / A
Ovicide – Budworm
Assail
70WP 1.1 oz. / A
Assail
30SG 1.5-2.5 oz. / A
Darkling Beetles
by Gene Burgess
The Plant Pest Diagnostic lab has been receiving
samples of darkling beetles in feed. The
question has been asked: Are they harmful to horses or cattle if they are accidently eaten?
The answer is no. Some people are
wandering if these are blister beetles, which cause a problem in cattle and
horses.
Some of the darkling beetles feed on grain products
in both larval and adult stages. These
adult darkling beetles are shiny dark brown to black and the head is narrower
than the segment immediately behind it.
The fore-wings are hard.
Blister beetles are narrow and elongate, the
fore-wings are soft and flexible and the head is larger than the segment
immediately behind it (thorax). These
beetles have forewings that are ash-gray, black, striped and margined. They produce a toxic substance called cantharidin at levels capable of poisoning livestock,
especially horses. They usually occur in
late summer.
SOY OIL SPRAYS INTRODUCED
by Darrell Hensley
A Canadian firm has begun marketing a range of
soybean oil-based products said to be biodegradable. Bionatrol-M
is formulated to control powdery mildew, grey mold, and other fungus-related
conditions in fruits, vegetables, and trees. Bionatrol-I
is said to control aphids, mites, and whiteflies without harming parasitoid
species. The manufacturer points out that both products, and a viruscide still in the testing phase, are residue
free. NTS Research
& Inc., Unit 108, 1680 Broadway St., Port Coquitlam,
BC, V3C 2M8, CANADA. Mailto:info@ntsresearch.com. Fax: 1-604-552-1265.
TOBACCO BLUE MOLD
by Darrell Hensley
Tobacco blue mold has been reported in five counties
of Kentucky. All infected plants have
originated from "mini" plugs which were shipped from Florida to
Kentucky and distributed to these counties.
Positive infections were reported in Montgomery, Adair, Magofinn, Morgan, and Boyle counties of Kentucky. More information concerning the status of
tobacco blue mold may be found at http://web.utk.edu/~extepp/bluesit.htm.
OTHER UT NEWSLETTERS WITH PEST
MANAGEMENT INFORMATION
http://web.utk.edu/~extepp/fpn/fpn.htm
Tennessee
Crop and Pest Management Newsletter
http://www.utextension.utk.edu/fieldCrops/cotton/cotton_insects/ipmnewsletters.htm
This and other "What's Happening"
issues can be found at http://web.utk.edu/~extepp/whatshap.htm
Disclaimer
This publication contains pesticide
recommendations that are subject to change at any time. The recommendations in
this publication are provided only as a guide. It is always the pesticide
applicator's responsibility, by law, to read and follow all current label
directions for the specific pesticide being used. The label always takes
precedence over the recommendations found in this publication.
Use of trade or brand names in this
publication is for clarity and information; it does not imply approval of the
product to the exclusion of others that may be of similar, suitable
composition, nor does it guarantee or warrant the standard of the product. The
author(s), the University of Tennessee Institute of Agriculture and University
of Tennessee Extension assume no liability resulting from the use of these
recommendations.
Precautionary Statement
To protect people and the environment, pesticides
should be used safely. This is everyone’s responsibility,
especially the user. Read and follow label directions carefully
before you mix, apply store or dispose of a pesticide. According to laws
regulating pesticides, they must be used only as directed by the label.
Persons who do not obey the law will be subject to
penalties.
Visit the UT Extension Web site at
http://www.utextension.utk.edu
Programs in agriculture and natural resources, 4-H
youth development, family and consumer sciences,
and resource development. University of Tennessee
Institute of Agriculture,
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county governments cooperating.
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