kentucky pest news august 10, 2010
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8/9/2019 Kentucky Pest News August 10, 2010
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Online at:www.uky.edu/KPN
Number 1242 August 10, 2010
CORN
-Southern Rust Prognosis
-Producing Late-Season Sweet Corn
-Brown Spot of Corn
SOYBEAN
-Watch for THESE Stinkbugs in Your
Soybeans!
FIELD CROPS
-Late Summer Caterpillars in Field Crops
CORN
Southern Rust PrognosisBy Paul Vincelli
Last week I toured a number of corn fields in
Mclean County (and enjoyed excellent
interactions with a group of Extension agents
and fellow industry representative; thanksfolks!). Southern rust was found but only in
localized hotspots. In other areas of the state,
Extension agents continue to scout for the
disease and have not yet seen it (although it hasbeen found also in Caldwell Co. and Graves
Co). Thus, southern corn rust appears to still be
at a relatively low prevalence in Kentucky.
Many corn crops in Western Kentucky are wellinto the dent stage, because of the combination
of early to timely planting, rapid accumulation
of heat units), and very dry weather during grainfill. Between the low prevalence of southern
rust and the rapid maturation and drydown of the
crop, it appears that many crops have escaped
the threat of significant damage from southernrust.
SHADE TREES & ORNAMENTALS
-Fall Webworms
-Walnut Thousand Cankers Disease A
Potential Threat
-Spruce Fungi Causing Needle Loss
LAWN & TURF
-Summer Patch of Kentucky Bluegrass
DIAGNOSTIC LAB HIGHLIGHTS
INSECT TRAP COUNTS
Of course, late-planted fields should still be
scouted for the disease. And all fields should be
checked for stalk strength as they dry down.
Producing Late-Season Sweet CornBy Ric Bessin
Producing sweet corn late in the season can be
one of the more challenging crops to produce
without insect damage. Insect management
techniques used to produce sweet corn for sale
in July are often insufficient for crops maturingin mid August and later. The problem is corn
earworm. During this time period, it is not
unusual to find 80% of the ear tips damaged by
this insect even when the plants were regularly
sprayed.
Lexington, KY 40546
Figure 1. Corn earworm larva in tip of corn ear.
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There are a couple of reasons for this. First, by
midsummer, much larger populations of corn
earworm are present and egg laying increases
proportionally. There are several generationsper year so by midsummer populations have had
a chance to buildup. By midsummer migratingpopulations are also arriving from southern
states.
Heat is the other reason why corn earworm is
more difficult to manage in midsummer. Heat
makes the corn silks grow faster and the corn
earworm eggs develop quicker. As new silk
emerges from the ear more rapidly, insecticides
may need to be reapplied more often to protect
the ears. Higher temperatures may reduce spray
intervals from 5 to 3 days with some
insecticides. Heat also has a negative influenceon pyrethroid insecticides, the most common
insecticide class used on sweet corn. The higher
the temperature, the less effective they are.
When examining sweet corn ears, keep in mind
that there can be a few different kinds of insect
larvae that can be found. Corn borers, both
European and southwestern will attack the ears.
Unlike corn earworm that attacks only the tip,
corn borers can damage the base and side of the
ear as well as the tip. Both of these larvae are
smooth and without the microspines found onthe corn earworm. Corn borers also have very
dark head capsules rather than the lightercolored head capsule of the corn earworm. Fall
armyworm will also attack the ear. The brown
fall armyworm has a dark head capsule with a
light colored inverted Y on the front of the
head.
Management of corn earworm in the
midsummer is not easy, but it is possible. First,
producers should think about how they are
applying their sprays. The only part of the plantneeding protection is the ear. So sprays should
be directed to the middle third of the plant.
Drop nozzles on ground equipment should be
angled toward the ear. Leaves can interfere withpenetration to the ear, so a nozzle angled
downward above the ear and one angled upward
below the ear on each side of the row can
improve coverage. Spray volume needs to besufficient to allow for through coverage.
Corn earworm management is preventive. We
must prevent it from entering the ear as onceinside we cant do anything to kill it. Generally
the first insecticide spray is applied when 50 to
70% of the ears first silk. Sprays are reapplied
at two to six day intervals based on pheromone
trap captures and temperature. With higher the
temperature and moth populations, producers
should shorten the spray intervals. Once the
silks dry, they are no longer attractive for egg
laying and insecticide sprays can be
discontinued.
Insecticides for corn earworm control includeAsana XL, Baythroid XL, Belt, Brigade,
Lannate, Larvin, Mustang Max, Pounce,
Proaxis, Radiant, and Warrior. Most of these are
pyrethroid insecticides (IRAC Group 3) and
some corn earworms in the Midwest appear tobe less sensitive than in the past. Belt, Lannate,
Larvin, and Radiant are from other non-
pyrethroid insecticide classes.
It helps to select the proper variety. Ears withgood tip coverage, tight husks, and long silk
channels help to limit kernel damage. Anothertool available to growers is the use of Bt sweet
corn. These varieties produce a protein that killsthe larvae and can provide up to 90% control,
but 90% control may not be enough when each
ear has a dozen or more corn earworm eggs.
Early-planted sweet corn may not need any
supplemental corn earworm controls, but by midAugust supplemental sprays are recommended.
Figure 2. Insecticide sprays need to begin at early silking.
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Larvae that do develop on Bt sweet corn are
small and damage is often restricted to just a few
kernels.
Brown Spot of CornBy Paul Vincelli
Last week I visited a corn field with brown spotdisease, caused by the fungus Physoderma
maydis. This disease does not occur widely in
Kentucky, though it is not unusual to see it pop
up here and there.
Infection by this fungus produces chocolate-
brown spots on leaf midribs and leaf sheaths.
Infections of the leaf blade tend to be small and
yellowish to yellowish-brown in color (Figures3-4). Often, brown spot symptoms appear as
diffuse bands of disease. This is because
infections often occur in the whorl, where
moisture accumulates. Since environmental
conditions in the whorl fluctuate, so does the
occurrence of infections as the corn tissue grows
through the whorl.
Brown spot rarely causes yield loss. However,
the brown spots on the sheath can raise concern
about stalk heath. Keep in mind, however, that
these are infections of the leaf sheath, not thestalk. The underlying stalk is healthy. Prove
this to yourself by removing a brown-spotted
sheath, and youll see healthy stalk beneath.
SOYBEAN
Watch for THESE Stinkbugs in Your
Soybeans!By Doug Johnson
By now stinkbugs will have begun congregatingin soybeans. Generally attracted by blooms, they
actually do their damage by feeding on the pods.
In Kentucky, our beans will be infested by green
and brown stink bugs. Yes, those are the colorsbut also the common names, of two of the
species. We might occasionally see a southern
green stink bug but they are by far in the
minority. The green and southern green stink
bugs look very much alike and there is no easyway to tell them apart.
Figure 3. Symptoms of Physoderma brown spot of
corn on the leaf blade. Note band of diseased tissue,
indicative of an infection period when that leaf tissue
was in the whorl.
Figure 4. Symptoms of Physoderma brown spot of cornon the leaf sheath. Note diagonal "banding" pattern,
indicative of sequential flushes of infection.
Figure 5. Green stink bug (R. Ottens, Univ. of
Georgia, Bugwood.org photo).
Figure 6. Southern green stink bug
(M. Shepard, G.R. Carner, and P.A.C.
Ooi, Bugwood.org photo).
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The brown stink bug complex is also usually
made up of two species, the brown stink bug and
the one spotted stink bug. You can sometimes
tell them apart by looking for a dark brown/
black spot on the underside of the rear end of themale one spotted stinkbug.
There are of course other species that might also
appear in much fewer numbers. At present wecount all of these species of stink bugs the same
for purposes of making a control decision. That
may change with the introduction of newspecies.
In addition dont forget that there are predatory
bugs around that may look like the brown stinkbug. Common predatory bugs are the spined
soldier bug and the spined assassin bug. These
are a good guy working for you. Dont count
these bugs with the pest stink bugs when making
a treatment decision!
So much for what has been, now what will the
future bring? There are three stink bug species
that are quite literally on our borders and could
change how we handle this insect pest complex.At present we are unaware that any of these
species have been captured in Kentucky, but
they could be close by and we are on the lookoutfor them.
Perhaps the most important is the red banded
stink bug. This pest originally from South
America, has been making life difficult forsoybean producers in the deep south for several
years. It often requires multiple insecticide
applications to obtain control. They are known
to occur as far north as southeastern Missouriand west Tennessee. This stink bug is rather
distinctly different in coloration from the greens
and browns that we normally find. They have
red coloration across the upper back and
sometimes along the sides of the back.
Fortunately, just because you find a stink bug in
your beans with red coloration, does not mean
that it is the redbanded stink bug. We also have a
redshouldered stink bug that naturally occurs in
Kentucky, though it not known to be a pest of
soybeans. Nevertheless if you find such a stink
bug in your beans it would be a very good ideato send the specimen(s) in for identification.
Figure 7. Brown stink bug (R. Ottens, Univ. of Georgia,
Bugwood.org photo).
Figure 8. Spinded shoulder bug (Clemson Univ.-USDA
CES Slide Series, Bugwood.org photo).
Figure 9. Spined assassin bug (W. Cranshaw, Colorado
State Univ., Bugwood.org photo).
Figure 10. Redbanded stink bug (R. Ottens, Univ. of
Georgia, Bugwood.org photo).
Figure 11. Red shouldered stink bug (W. Cranshaw,
Colorado State Univ., Bugwood.org photo).
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States to our immediate north and Tennessee are
known to have the brown marmorated stink bug.
The adults might have entered the United States
as stowawaysin packing crates from Asia.This
insect is a know pest of many fruit and pod
producing crops, including soybeans; in its
native China, South Korea, Japan, and Taiwan.However, it is likely to be most problematic as
an invader of buildings. Once inside it is very
difficult to control, and produces an extremelyoffensive odor. This pest will be somewhat
difficult for the untrained eye to differentiate
from our normal complex of brown stinkbugs.
The last two antennal segments have alternating
light and dark bands.
A little bit farther afield we find the latest
invasive stink bug the bean plataspid. This pest
was discovered last fall (2009) in northeastGeorgia. In 2010 its range has expanded within
Georgia and into South Carolina. They have
been observed feeding on soybean, but like the
brown marmorated stink bug, the bean
plataspids major impact is likely to be the
invasion of structures. This is an odd lookingcritter, that is easily identified once seen. Unlike
our normal stinkbug complex, when in soybeans
this pest appears to prefer feeding on stems and
petioles as opposed to pods.
Because of their differential damage potential
and difference in ease of control, it is important
for us to know which of these stink bugs are in
our soybean fields. To that end entomologist at
the University of Kentucky and our county
extension agent colleagues are involved in amonitoring program for these and other invasive
species. We are interested in establishing two
items: 1.) What is the current make of thestinkbug complex in our soybeans. 2.) Are any
of these invasive stinkbug species already
present in Kentucky? The former provides an
important baseline with which we can compare
future populations, particularly when theinvasive species arrive. The latter will help us
understand when, where and how these invasive
stinkbugs may affect our crop production
systems. We are looking first at soybeansbecause it is a common host, but these stink
bugs are pests of many other crops.
When you are sampling soybeans you may wish
to send samples of stinkbugs to the University of
Kentucky for identification. If so, you may take
samples to your county extension office or send
the stink bugs directly to Dr. Doug Johnson,
UK-REC, 1205 Hopkinsville St. Princeton, KY
42445. These samples will help us establish our
base line of species and to detect them early
should one if the new stink bugs arrive!
FIELD CROPS
Late Summer Caterpillars in Field CropsBy Lee Townsend
Several species of caterpillars can be found now
on alfalfa, corn, soybean, and tobacco. Many are
distinctive and easy to recognize. Begin by
looking at the numbers of pairs of fleshy legs onthe underside of the abdomen. These can be seen
most easily if you look at the caterpillar from the
side. Most have 5 pairs with 4 on consecutive
segments and a 5th pair on the last segment.Other features such as head and body coloring,
hairs, and spines on the body also help with
identification.
_____
Figure 12. Brown marmorated stink bug (D.R. Lance,
USDA APHIS PPQ, Bugwood.org photo).
Figure 13. Bean Plataspid (D. Suiter, Univ.
Georgia photo).
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Loopers or inchworms have adistinct crawling motion
because of the reduced
numbers of prolegs (2 or 3
pairs) on the abdomen.1 2 3
A
common
looper inKentucky
soybean
has a
purple-
brown band along the center of the back. It is
about an inch long when full grown and may be
found on a variety of crops, plants, and trees
from June to October.
_____
1 2 3 4
The green
cloverworm
can be very
abundant in
alfalfa and
soybean.
There are 4
pairs of
fleshy abdominal legs, the last pair extends backfrom the end of the body. This lime green
caterpillar has thin white stripes running thelength of the body. It moves with a looping
motion and thrashes violently when disturbed.
_____
Most caterpillars have 5 pairs of flesh legs andmove more smoothly
than the looping crawl of
the previous types.
1 2 3 4 5
The alfalfa
caterpillar has a
velvety greenbody with a
narrow white
stripe along each side; there is a fine red line inthe white stripe. They are about 1.5 inches long
when full grown. It is found on legumes.
The silverspottedskipper is easily
recognized by thepair of orange
spots on its dark
brown head and anarrow black
neck behind the
head. The larvae
use silk to form
leaves into aretreat or protective shelter. It feeds on legumes.
The yellow bearcaterpillar is
very common in
crop fields.
These woolly
caterpillars are
covered with
soft fine hairs.
They vary from
almost white to
yellow to nearly black. Mature larvae are about
1.75 inches long.
The saltmarsh
caterpillar also
is a woolly
species but can
be recognized
by the distinctbumps or warts
on the body.
Coloring of this species can vary from blonde to
black. They will feed on many plants, crops, and
trees. Full grown larvae are about 2 inches long.
The thistle
caterpillaris a spiny
caterpillar
with
variable
Figure 14. Common looper.
Figure 15. Green cloverworm.
Figure 16. Alfalfa caterpillar.
Figure 17. Silverspotted
skipper.
Figure 18. Yellow bear caterpillar.
Figure 19. Saltmarsh caterpillar.
Figure 20. Thistle caterpillar.
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colors. They feed on many plants includingsoybeans and live in a loose nest of silken
webbing. Mature larvae are about 1.75 inches
long.
Three stripedcaterpillars can
be present in
crop fields inlate summer:
fall armyworm,
corn earworm
(soybean
podworm), and the
yellowstriped
armyworm. The
fall armyworm and
corn earworm aremost similar but
can be
distinguished by
looking at the head.
The head of the
corn earworm is yellow-brown with nomarkings. The head of the fall armyworm has
mottled or net-like markings and two distinct
light bars that converge in a V at the top of the
head. Fall armyworms feed on corn, grasses, and
legumes. They can destroy late summer seedings
of grasses and forages.
The
yellowstriped
armyworm has
the yellow-
brown head of
the corn
earworm but
can be
recognized by the yellow stripe running along
each side and a distinct black spot on each sidebehind the last pair of segmented thoracic legs.
These larvae are about 1.25 inches long when
feeding is complete.
SHADE TREES & ORNAMENTALS
Fall WebwormsBy Lee Townsend
The light
gray silktents of fall
webworm
caterpillarsare showing
up now at
the ends of
branches of
over 100species of forest and shade trees. The worms are
covered by pale green or yellow hairs and have
rows of black spots along their backs. Groups of
these caterpillars can be found in webbing at theend of branches on caterpillars feed on leaves
inside the webbing and expand the "tent" as they
require more food.
Usually, the infestation is limited to a branch or
two on a plant and the impact is aesthetic rather
than a plant health threat. Removal and
destruction of the web and caterpillars is an
effective control measure.
Walnut Thousand Cankers Disease A
Potential ThreatBy John Hartman and Lee Townsend
Thousand Cankers Disease (TCD) is a recently
recognized disease of walnuts (Juglans spp.).
The disease results from the combined activity
of the walnut twig beetle (Pityophthorus
juglandis) and a canker producing fungus called
Geosmithia. TCD has been active in the western
United States for a decade but the cause was
only recently described. TCD has been involvedin several large scale die-offs of walnut,
particularly black walnut (Juglans nigra),
growing in the west. In the past few weeks,
investigators in Tennessee may have found the
first case of TCD in an eastern state. If TCD is
present in Tennessee, it surely represents a threat
to black walnut plantings in Kentucky.
Figure 21. Three striped caterpillars.
Figure 22. Yellow striped
armyworm.
Figure 23. Yellow striped armyworm.
Figure 24. Gray silk tent.
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Symptoms. Trees infected with the causalfungus first develop yellow leaves and
eventually twig and branch decline and dieback
(Figure 25). The fungus causes a canker, visible
by peeling back the bark, corresponding to theactivity of the insect vector in the branch or limb
(Figure 26). When multiple cankers develop onthe limbs (Figure 27) the vascular system is so
disrupted that the limb dies. The combination of
disease-causing fungus and insect vector is alethal combination for walnuts.
Disease vector. The walnut twig beetle
(Pityophthorus juglandis), the vector of
Thousand Cankers Disease (TCD), is native toNew Mexico and Arizona where its distribution
follows that of Arizona walnut, the likely nativehost. This 1.5 to 1.9 mm long yellow brown bark
beetle aggressively attacks black walnut and
carries the pathogens associated with TCD.Contrary to its common name, beetle attacks are
not confined to twigs; tunneling is most
commonly seen in branches greater than 0.7
inches in diameter and sometimes in trunks.
The adult female begins to tunnel in walnut by
early May to form a nuptial chamber with 1 or
more radiating egg galleries. The small, white
legless larvae develop below bark. A generation
from egg to adult takes a little less than 2
months. However, adults can be present from
mid-April through early October.
Urban and parkland trees have been infected
with TCD. Kentucky arborists, homeowners,
and woodlot owners need to be alert to thepossibility of TCD and report suspicious cases
of walnut decline to local County Extension
Agents and foresters.
Figure 25. Walnut yellowing dieback caused
by thousand cankers disease (Photo by W.
Cranshaw, Colorado State University).
Figure 26. Canker on walnut limb caused by
the fungus Geosmithia (Photo by N. Tisserat,
Colorado State University).
Figure 27. Multiple coalescing cankers on walnut
limb illustrate destructive potential of thousand
cankers disease (Photo by N. Tisserat, Colorado
State University).
Figure 28 & 29. Dorsal and lateral views of the
walnut twig beetle, the head is completely
hidden from view, a characteristic of many bark
beetles (Photo by J. LaBonte, Oregon Dept of
Ag).
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Spruce Fungi Causing Needle LossBy John Hartman
During recent weeks, numerous samples of
spruce twigs and branches shedding yellow or
brown needles have been observed in the Plant
Disease Diagnostic Laboratory and in severallandscapes. Symptoms have included
yellowing, browning and shedding of current
and especially last years needles resulting intwig and branch dieback.
Normal needle drop. Spruce and fir trees
typically retain their needles for several years.
In most years, needle drop is hardly noticeable
without careful examination of the inner
branches where a few scattered needles may turn
yellow and drop in late spring or early summer
of their third year. Normal needle drop is aseasonal occurrence and can vary from tree totree and from year to year. Sometimes these old,
yellow needles can harbor saprophytic fungi, but
these fungi are unlike the parasitic fungi that
appear on younger needles.
Two needle cast diseases. The fungi
Rhizosphaera kalkhoffii and Stigmina lautti are
the causes of needle cast being seen now on
spruce trees in Kentucky.
Rhizosphaera needle cast symptomsconsist of yellowing first-year or olderneedles in summer which later turn
brown and drop (Figure 30), perhaps 15
months after initial infection. Thus,
needles dropping now could be the
result of infections that occurred last
summer, 2009 (a wet season here in
Kentucky). Diseased needles contain
fungal signs in the form of dark
spherical pycnidia which typically
emerge from the needle stomata and are
thus lined up in rows (Figure 31). These
rows of pycnidia protruding through thestomata can be seen with the aid of a
hand lens, and are pretty diagnostic for
this disease. Damage typically starts on
the lower branches and moves up the
tree. After 3 to 4 years of severe
infection the lowest branches may begin
to die. Colorado blue spruce, Picea
pungens, is highly susceptible to this
disease. White spruce, P. glauca, is
intermediate in susceptibility and
Norway spruce, P. abies, is relativelyresistant. Trees that are stressed from
drought, poor planting practices, or
other factors are more likely to suffer
from Rhizosphaera needle cast. Stigmina needle cast has also been
observed on shedding spruce needlesthis year (Figure 32). Stigmina is
associated with spruce needle symptoms
and signs almost identical to those of
Rhizosphaera. Stigmina produces dark
spore-bearing structures in the needle
stomata (Figure 33), but under a hand
lens or a dissecting microscope, they
appear bushy compared to the
compact pycnidia ofRhizosphaera.
Without some magnification, the twodiseases appear to be very similar.
Figure 30. Spurce needles; brown needles
have symptoms of Rhizosphaera needle cast
disease (P. Bachi photo).
Figure 31. Close-up ofRhizosphaera
pycnidia lined up in rows corresponding to
spruce needle stomata (P. Bachi photo).
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Other causes of needle cast. Another spruceneedle drop is caused by a newly identified
fungus, Setomelanomma holmii. This needledrop disease has not been found in Kentucky as
far as can be determined. Yellow, sickly needles
can also result from an infestation of spruce
spider mites. Although spider mites are found
on spruce in Kentucky, they have not beenobserved as frequently as the Stigmina and
Rhizosphaera needle casts this year.
Improving the health of landscape spruce trees.
Spruce health is enhanced by providing goodgrowing conditions.
Provide one inch of water per weekduring times of drought. Be sure the
water is applied over the root zone and
avoid getting the foliage wet.
Mulch underneath the trees to retainmoisture. Grass competes very well and
can actually contribute to water stress on
trees.
Prune out diseased and dying branches(only under dry conditions) and take
them away for burning or burial.
Pruning tools should be sterilized with
70% alcohol between cuts. If needle cast disease has been
diagnosed, a spring treatment with a
chlorothalonil-based fungicide may
provide protection. Timing of the
treatment should coincide with needleemergence and be repeated as necessary
until full needle emergence has
occurred.
Avoid unnecessary trunk or branchinjuries.
LAWN & TURF
Summer Patch of Kentucky BluegrassBy Paul Vincelli
Summer patch was diagnosed several weeks ago
on a Kentucky bluegrass athletic field in Central
Kentucky. This disease commonly appears as
circular or crescent-shaped dead patches
measuring a few inches to two to three feet(Figure 34). When the disease is most active,
the margins of affected patches can have a
slightly bronze color as the plants die. This
bronze color is evidence of active disease
progress. Tufts or patches of healthy turfgrass
tillers sometimes appear in the center of affected
patches.
Figure 32. Spruce needles fading and
turning brown due to Stigmina infection.
Note that the foliage appears to be thinned
out (P. Bachi photo).
Figure 33. Close-up ofStigmina emerging
from spruce needle stomata (P. Bachi
photo).
Figure 34. Summer patch of Kentucky bluegrass.
Note bronze margin indicating the zone of active
root infection.
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This is a root disease (Figure 35), caused by a
common fungus in our soils. The rather early
appearance of this late-summer disease is due to
the hot conditions the turf has experienced this
summer.
Management of the disease is difficult if the
variety is susceptible to summer patch. For
severely affected sites, renovation to tall fescue
or a resistant variety of Kentucky bluegrass isrecommended. Information on the best-
performing turfgrass varieties can be found at
http://www.uky.edu/Ag/ukturf/Top%20Turfgras
s%20Varieties.pdf.
Management on sites with low to moderate
levels of disease should include the following:1. Make sure the mowing height is 2.5-3.0
inches. Avoid scalping the turf.
2. If choosing to irrigate, irrigate deeplyand infrequently. Avoid irrigating
lightly and frequentlythat helps to
promote the fungal infections of the
roots.
3. Regular use of ammonium sulfate,ammonium chloride, or sulfur-coated
urea as a nitrogen source can reduce the
severity of summer patch. Avoid nitrate-
containing fertilizers for these sites.
More information on the biology and
management of summer patch can be found in
the UK Extension publication, Patch Diseases
in Kentucky Bluegrass Lawns, available at
http://www.ca.uky.edu/agc/pubs/id/id122/id122.
pdf.
DIAGNOSTIC LAB HIGHLIGHTSBy Julie Beale and Paul Bachi
Recent agronomic samples in the PDDL have
included crazy top and boron deficiency on corn;Rhizcotonia and Fusarium stem rots on soybean;
Pythium root rot on alfalfa; brown stripe onorchardgrass; black shank, blue mold, soreshin,
Pythium stem rot, frogeye leaf spot, bacterial
soft rot and frenching on tobacco.
On fruit and vegetable samples, we have
diagnosed Phytophthora root rot on raspberry;
black rot and flyspeck on apple; bacterial spot
on peach; Fusarium crown rot on asparagus;
southern rust on sweet corn; Microdochium
blight on pumpkin; anthracnose, early blight,
Septoria leaf spot, root knot nematode and
Fusarium wilt on tomato.
On ornamentals and turf, we have seen southern
blight on rudbeckia; black root rot on holly;
Phytophthora root rot on itea, rhododendron and
sassafrass; Botryosphaeria canker on blackgum
and lilac; bacterial leaf scorch, Actinopelte leaf
spot, powdery mildew, anthracnose and
Phytophthora root rot on oak; Pythium root rot,
brown patch and heat injury on bentgrass; spring
dead spot on bermudagrass; and brown patch on
fescue.
INSECT TRAP COUNTS
July 30-Aug 6
Graphs of insect trap counts for the 2010 season are
available on the IPM web site at -http://www.uky.edu/Ag/IPM/ipm.htm.View trap counts for Fulton County, Kentucky at -
http://ces.ca.uky.edu/fulton/InsectTraps
Location Princeton,
KY
Lexington,
KY
Black cutworm 9 64
Armyworm 21 3
Corn earworm 51 29
European corn
borer
3 4
Southwestern
corn borer
4 0
Fall armyworm 7 0
Figure 35. Microscopic view of the surface of a
Kentucky bluegrass root, showing the dark
filamentous growth of the summer patch fungus.
http://www.uky.edu/Ag/ukturf/Top%20Turfgrass%20Varieties.pdfhttp://www.uky.edu/Ag/ukturf/Top%20Turfgrass%20Varieties.pdfhttp://www.uky.edu/Ag/ukturf/Top%20Turfgrass%20Varieties.pdfhttp://www.ca.uky.edu/agc/pubs/id/id122/id122.pdfhttp://www.ca.uky.edu/agc/pubs/id/id122/id122.pdfhttp://www.ca.uky.edu/agc/pubs/id/id122/id122.pdfhttp://www.ca.uky.edu/agc/pubs/id/id122/id122.pdfhttp://www.ca.uky.edu/agc/pubs/id/id122/id122.pdfhttp://www.uky.edu/Ag/ukturf/Top%20Turfgrass%20Varieties.pdfhttp://www.uky.edu/Ag/ukturf/Top%20Turfgrass%20Varieties.pdf
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