UMass
Extension Landscape Message #13
May 26, 2006
The
LANDSCAPE MESSAGE is an educational newsletter intended
to guide landscape, nursery and urban forestry professionals
in identifying pests in the landscape, monitoring their
development, planning management strategies and creating
site-specific records for future management reference.
UMass
Extension has updated this issue to provide timely
pest management information and the latest regional news
and environmental data throughout Massachusetts. The
next update will be available on Friday,
June 2, 2006.
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Message Archive.
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ENVIRONMENTAL
DATA
The following growing-degree-day (GDD) and precipitation
data was collected for a one-week period, May 18, 2006 through
May 24, 2006. Soil temperature and phenological indicators were
observed on May 24, 2006. Accumulated GDDs represent the heating
units above a 50° F
baseline temperature collected via our instruments since
the beginning of the current growing season. This information
is intended for use as a guide for monitoring the developmental
stages of pests in your location and planning management
strategies accordingly.
| Region/Location |
2006 GROWING DEGREE DAYS
|
Soil
Temp
(°F
at 4" depth) |
Precipitation
(1-Week
Gain) |
1-Week
Gain |
Total
accumulation for 2006 |
| Cape Cod |
60 |
194 |
58° |
0.50" |
| Southeast |
52 |
217 |
58° |
0.49" |
| East |
51 |
243 |
60° |
~0.50" |
| Central |
40 |
171 |
45° |
1.59" |
| Pioneer Valley |
33 |
249 |
60° |
0.91" |
| Berkshires |
20 |
177 |
63° |
1.39" |
AVERAGE |
46 |
208.5 |
57.3° |
0.90" |
n/a = information
not available |
REGIONAL
NOTES
Cape
Cod Region (Barnstable) - General
Conditions: The cape has been cool and partly sunny for
the past week, with widely scattered showers occurring. We missed
the deluge of Sunday, May 21. Landscape plants are in good condition,
with many spring flowering shrubs giving color to the landscape. Pests/Problems: Many
trees are beginning to show signs of defoliation along the Rt.
6A corridor. Tent caterpillar webs are large and wide-spread. Nantucket
pine tip moths are flying. Oak, maple and sycamore are showing
signs of anthracnose. Native flowering dogwood is exhibiting spotted
and distorted bracts, while Kousa dogwood has some leaf spot. Cedar-apple
rust is showing on the foliage of susceptible crab-apples. Peony
blight is beginning to show up.
Southeast
Region (Hanson) - General Conditions: Cool, sunny weather
has been the norm this past week. Soils are moist. Hanson received
0.49 inches of rain. Wisteria, Fothergilla, flowering dogwood,
Helleborus foetidus, Vinca, Pulmonaria, Trillium, Corydalis
lutea, anemones, royal azalea, bleeding heart, Euphorbia polychroma,
Brunnera macrophylla, Epimedium, Phlox subulata,
Phlox divaricata, Phlox stolonifera, sweet woodruff, columbine,
barberry, viburnums, Rutgers hybid dogwoods, Daphne x burkwoodii 'Carol
Mackie', Euonymous alatus, tree peonies, Dicentra
eximia , lily of the valley, and Soloman's seal are in full
bloom. Goldenchaintree is beginning to bloom. Halesia and eastern
redbud are past bloom. Pests/Problems: Oak and
ash are producing foliage slowly, and the oaks sampled had mixed
populations of gypsy moth, forest tent and winter moth caterpillars.
Some ash trees look nearly bare, like it is winter instead of May.
The Plymouth County Extension office continues to receive reports
of small gypsy moth caterpillars causing skin irritation after
being found on the arms, legs, and necks of people outside in the
landscape. Gypsy moths are about 3rd instar and have settled to
feed. Gypsy moth, eastern tent, forest tent and winter moth caterpillars,
hemlock woolly adelgid, lily leaf beetles, wasps and hornets, carpenter
bees, mosquitoes, mayflies, and ticks are all active. With all
the wet weather, leaf spots are starting to show up on a wide range
of woody and herbaceous material. Buttercups, ground ivy, chickweed,
veronica, violets and dandelions are in full bloom. Beneficial
insects are active. Barberry and burning bush, two Massachusetts
invasive plants, are in bloom. If future potential seed dispersal
is of concern to clients who may not wish to remove and destroy
the plants, an alternative may be to or prune or shear plants
now to remove flowers. Seed production will be interrupted, and
plants will grow and fill in nicely while producing fewer seeds.
East
Region (Boston) - General Conditions: No report
Central
Region (Boylston) - General Conditions: No report.
Pioneer
Valley Region (Amherst) - General Conditions: A
lush green and flowered spring continues in the Pioneer Valley. Pests/Problems: In
addition, the prolonged periods of wet weather provides excellent
opportunities for leaf and shoot diseases.
Berkshire
Region (Great Barrington) - General Conditions: With
soil temperatures warming and soil moisture levels being very good,
conditions are ideal for planting and for plant growth. Pests/Problems: Forest
tent caterpillars have appeared in very high numbers in certain regions of Berkshire
County. Population levels for eastern tent caterpillars have also been quite
high. Moist conditions and warming temperatures are expected to bring about high
mosquito populations.
PHENOLOGY
The phenological indicators are a visual tool for
correlating plant development with pest development. The following
are the indicator plants and the stages of bloom observed
for this period:
Indicator Plants - Stages
of Flowering (begin, full, end) |
PLANT NAME (Botanic/Common) |
C.C. |
S.E. |
EAST |
CENT. |
P.V. |
BERK. |
|
|
| Cotoneaster horizontalis (Rock
Cotoneaster) |
* |
begin |
* |
* |
full |
* |
| Syringa Meyeri (Meyer
Lilac) |
begin |
begin |
* |
begin |
full |
* |
| Enkianthus campanulatus (Redvein
Enkianthus) |
begin |
begin |
* |
full |
full |
b/full |
| Rhododendron 'Exbury' (Exbury
Azalea) |
* |
begin |
* |
full |
full |
full |
| Aesculus hippocastanum & rel.
sp. (Horsechestnut) |
begin |
b/full |
* |
full |
full |
full |
| Lonicera tatarica (Tatarian
Honeysuckle) |
begin |
full |
* |
* |
full |
full |
| Viburnum plicatum (Japanese
Snowball) |
begin |
full |
* |
* |
* |
* |
| V. plicatum var. tomentosum (Doublefile) |
begin |
full |
* |
full |
full |
* |
| Sorbus spp. (Mountainash
species) |
begin |
full |
* |
full |
* |
* |
| Deutzia gracilis (Slender
Deutzia) |
* |
full |
* |
full |
* |
begin |
| R. catawbiense (Catawba
Rododendron) |
full |
full |
* |
begin |
full |
b/full |
| Spirea vanhouttei (Vanhoutte
Spirea) |
* |
full |
* |
begin |
* |
* |
| Cytissus scoparium (Scotch
Broom) |
full |
full |
* |
* |
* |
* |
| Elaeagnus umbellata (Autumn
Olive) |
full |
full |
* |
full |
* |
* |
| Rhododendron spp. (early
Azaleas) |
full |
full |
* |
full |
f/end |
full |
| Cornus florida (Flowering
Dogwood) - bracts |
end |
full |
* |
full |
f/end |
full |
| R. carolinianum (Carolina
Rhododendron) |
f/end |
f/end |
* |
* |
end |
* |
| Kerria japonica (Japanese
Kerria) |
full |
end |
* |
full |
full |
* |
| Syringa vulgaris (Common
Lilac) |
f/end |
end |
* |
full |
f/end |
full |
| Halesia spp. (Silverbell) |
* |
end |
* |
* |
end |
full |
| Malus spp. (Crabapple) |
f/end |
end |
* |
end |
end |
f/end |
| Cercis canadensis (Redbud) |
f/end |
end |
* |
end |
end |
f/end |
* = no activity
to report/information not available |
CAPE
COD REGION - Roberta Clark, Horticulturist for Barnstable County,
Barnstable.
SOUTHEAST REGION - Deborah Swanson, Horticulturist for UMass Extension
in Plymouth County, Hanson.
EAST REGION - James R. Allen, Horticulturist and Greenhouse Manager
for UMass Biology Department, Boston.
CENTRAL REGION - Joann Vieira, Superintendent of Horticulture, Tower
Hill Botanic Garden, Boylston.
PIONEER VALLEY - Dan Gillman, Plant Pathologist, UMass Extension
Plant Diagnostic Lab, UMass, Amherst.
BERKSHIRES - Ron Kujawski, Specialist, UMass Extension Landscape,
Nursery & Urban Forestry Program, Amherst.
WOODY
ORNAMENTALS
INSECTS
The warmer and sunnier weather is now strongly driving the development and activity
of many caterpillar species that have been somewhat delayed by the mostly cool
wet weather of the past two weeks. A number of the species, such as winter moth,
forest tent caterpillar, gypsy moth and fall cankerworm experienced staggered
egg-hatching, and in some areas there is a sharp difference in the sizes of caterpillars
within a species. However, they are all now feeding voraciously, and defoliation
should appear rapidly.
Lepidopteran Caterpillars:
-
Winter
moth -
caterpillar is now large enough to be seen with the naked eye, and it is feeding
on expanding (and fully expanded) foliage. However, there is a range in sizes
due to the 10-day staggered hatch period. Damage is now becoming apparent and
will increase exponentially over the next two weeks. Monitor for holes in the
foliage and the green inchworms. This pest is once again in large numbers in
much of eastern MA and most of RI. Common hosts are maples, crabapple, apple,
birch, oaks, and many other deciduous hosts. Feeding will continue until approximately
the end of May, depending on the weather. During the spring of 2004, winter moth
began pupation around May 22. Last year, which experienced cooler temperatures,
winter moth was actively feeding into the first week in June. So far this year,
we are expecting that winter moth will pupate around the end of May or during
the first week in June. Choices for management now are a spinosad product orone of the registered and labeled chemical insecticides. It is now too late for
B.t.K. to be effective given the age of the caterpillars.
-
Fall
cankerworm has begun its activity
but remains rather small. It really won't become a noticeable
threat until winter moth caterpillars are fairly mature.
This pest will continue to feed into June. Fall cankerworm
is usually green but does become very dark when in large
population numbers. Where winter moth has only two pairs
of prolegs, fall cankerworm has a partial third pair (most
anterior pair), which distinguishes it from winter moth.
It is said that fall cankerworm has two and a half pairs
of prolegs. Oaks are the preferred host, but it does have
a rather wide host plant range. Controls are the same for
this pest as they are for winter moth. See the following
web page to see photographs that compare winter moth caterpillars
to that of fall cankerworm: http://www.umassgreeninfo.org/fact_sheets/defoliators/wm_id_man.html.
-
Eastern
tent caterpillar (ETC) remains very active
now, and their silken webs in the crotches of branches
are very noticeable; in most cases there are multiple
webs per tree. Defoliation is already apparent in many
places. This will be one more outbreak year for ETC in
MA and many surrounding states. Feeding will continue
on Malus and Prunus until
late May or early June. Once the larvae mature, they can
be seen crawling across the ground, roads, etc. in search
of a sheltered pupation site. It is too late for B.t.K.
to be effective, but the other registered controls that
are labeled for lepidopteran caterpillars should all work
well at this time. Right now in the Amherst area, eastern
tent caterpillars have become quite large and is quickly
nearing the end of its feeding cycle. In many cases, host
trees are now completely defoliated.
-
Forest
tent caterpillar (FTC) is very active statewide
and is feeding on foliage. This pest also has a wide
host range, but in western MA they are mostly on sugar
maple and some oaks. In eastern MA this pest is primarily
found on oaks. Much defoliation is expected once again
from this pest. Control measures are the same as listed
above. This species does not make a noticeable silken
web, but they are often seen during the day huddling
together in very large clusters along the trunks and
branches of the host plant. In western MA this caterpillar
is already an inch long, and defoliation is becoming
apparent. Some trees are draped with silk along the trunks
and branches. Feeding will continue into June. This pest will achieve a final
caterpillar size of almost three inches. At that point, they are voracious feeders.
In eastern MA where it has been cooler, these caterpillars are currently much
smaller than those in the western parts of the state. It is now too late for
B.t.K. for FTC.
-
Gypsy
moth caterpillars have been blowing around
on silk in search of an acceptable tree to feed on. Deborah
Swanson in Plymouth County has received numerous calls
from nursery workers and landscapers that have experienced
these tiny caterpillars landing on their neck and other
areas of exposed skin. In most cases, very itchy and
annoying rashes result from the urticating (irritating)
hairs of these caterpillars. Some people are so sensitive
that they develop 'hay fever-like' reactions from exposure
to this caterpillar with symptoms such as itchy and watery
eyes to sneezing and runny noses. Those with severe reactions
may need to consult a physician. Treat this pest with
a spinosad product or one of the registered and labeled
pyrethroid insecticides. In many places it may be too late for B.t.
-
Larch
casebearer resumed activity as soon as the
buds started to open on their host plants (larch). These
tiny caterpillars overwintered within needle tips (their
case) on the trunks and branches. They have now moved out
onto the foliage and are actively feeding at the needle tips.
A spinosad product or one of the registered chemical insecticides
will work well now if deemed necessary. Parasites usually keep this pest in low
numbers; therefore, it is best to use a product that has the least effect on
these beneficial organisms.
Hymenopteran Caterpillars (Sawflies):
- European pine sawfly remains active.
Eggs, in the form of blocky yellow patches, started to
appear within the last two weeks. Caterpillars began
to hatch in the warmer regions more than a week ago.
Feeding injury is beginning to appear. These caterpillars
become voracious feeders as they grow and are capable of consuming large amounts
of foliage daily. Monitor for their presence now, and treat the very young caterpillars
with an insecticidal soap or a product that contains spinosad or use one of the
registered chemical insecticides. Mugo pine is one of the more common hosts for
this pest.
- Azalea sawfly
is now active in the warmer regions of the Amherst area, which currently
has accumulated more GDD's than other parts of the state. The coloration and
posture of this caterpillar on the plant (usually Exbury and Mollis azaleas =
deciduous) are so cryptic that much damage can be created before it is noticed.
Monitor for the appearance of feeding damage that leaves nothing but the main
veins. Then inspect much more closely for the green caterpillars that hug the
margins of the foliage and that are almost the same color as the foliage. Treat
with a product that contains spinosad.
Beetles:
- Lily
leaf beetle
is
active. Inspect for the bright red adult beetles,
which are foraging and beginning to feed. Within
a few weeks, start to inspect the undersides of
foliage for short (about one inch long) irregular
shaped, tan-colored lines that are actually a row
of eggs. Once found, they can be removed and destroyed.
Just before these eggs hatch, they will turn orange
and then a deep red color. Nymphs, which won't
appear for several more weeks, can be treated with
a product that contains spinosad.
- Viburnum leaf beetle has not yet
been reported in MA. To date, it has only been found
once in the state, and that was in extreme western
MA two years ago. However, it does exist in sufficient
numbers in surrounding states and is expected to invade
again. Be aware of this pest and its signs. Viburnum
leaf beetle can be easily moved on plants, so inspect
plants carefully before moving them into MA. Visit
the following web site from Cornell for outstanding
information about this pest: http://www.hort.cornell.edu/vlb

Piercing-Sucking Insects and Mites:
- Spruce spider mite
is active. Damage in the form of fine yellow stippling that contributes
to an overall appearance of chlorosis has now become obvious from last fall's
feeding. Monitor for these two-toned (tan color) mites with a hand lens, and
treat if numbers appear to be high. Oil sprays (at the summer rate) work well
on all life stages, but take caution with tender new foliage that is now emerging
from the buds. In such cases, it may be prudent to wait until it has fully expanded
to apply oil. Some of the newer mite growth regulator products can be quite effective
on the egg stage (ovicidal) and immatures of many spider mite species (Tetranychidae)
while not being harmful to predatory mite species. Adult spider mites are often
not killed by exposure to these products, but exposed female mites may produce
inviable eggs.
- Hemlock eriophyid mite
is active. These tiny, peg-shaped and pale yellow mites are just visible
to the naked eye and can be seen feeding actively on the needle surface. Large
populations will lead to much chlorosis and plant stress. Manage when found in
large numbers.
- Balsam twig aphid is active. The
'stem mothers' have been feeding and have now produced
many offspring that are capable of creating much feeding
injury in the form of needle distortion and much sticky
honeydew. True firs, such as Balsam and Frasier, are
most susceptible. High numbers of this pest can render
Christmas trees unfit for sale.
- Snowball aphid is nearing the end of its feeding cycle for the year. Its preferred hosts are
certain viburnum species, such as Korean spicebush, cranberry viburnum, mapleleaf
viburnum as well as others. When the aphids hatch they begin to feed with their
piercing-sucking mouths on newly expanding foliage, which causes severe leaf
curling and distortion. The aphids continue to feed through the rest of April
until about the end of May within the confines of the curled leaves. Their feeding
does not kill the foliage nor does it create yellow-stippling injury that is
so typical to other piercing-sucking insects. However, it can create so much
leaf distortion that it de-values the aesthetics of affected plant material.
Imidacloprid that is already systemic within the plant from last summer works
very well. Treating with a contact insecticide offers little management given
that these aphids are so well hidden within the curled foliage. In the Amherst
area, new leaves have already been affected, and in most cases it is too late
for treatments.
- Larch adelgid is
active and can be seen as white cottony masses scattered
throughout the needles of its host. When in large and
very noticeable numbers, it should probably be managed.
- Pine bark adelgid is active again, and large populations can appear like wind-driven snow on trunks
and the undersides of scaffold branches of white pine. Although very showy, it
rarely requires treatment.
- Hemlock
woolly adelgid (HWA)
has
been producing crawlers for the past two to three
weeks, and they are now settled and feeding. The
crawler stage is a very dangerous time for this pest
to be moved from plant to plant or to different locations (by wind, birds, humans
or wildlife). Once settled, they begin to feed and are not mobile again until
the next generation of crawlers in June. Oil sprays (summer rate) work very well,
but care should be taken to avoid applying oils when tender new foliage is appearing.
Systemically applied imidacloprid is also effective, but translocation can take
anywhere from weeks to months to get to where this pest is feeding.
- Honeylocust
plantbug is active. The overwintering
eggs have been imbedded in the tender shoots, and
they hatched at bud break. The tiny, pale green nymphs
are now feeding with their piercing-sucking mouths
on expanding foliage. When this pest occurs in large
numbers and the weather becomes cool for an extended
period of time (many days to more than a week), the
injury can become great to tiny foliage to the point
where it never fully expands. During certain years,
honeylocust can be defoliated by this piercing-sucking
pest. Monitor by shaking branches over a sheet of paper
and inspecting for the nymphs. When numbers are high,
it may be prudent to treat.
Leaf Miners:
- Inkberry leafminer
mines are obvious. Despite the larvae being in the mines since early last summer,
the browning of these mines has only just occurred within the past month or two.
Make note of plants with noticeable infestations, and prepare to place yellow
sticky cards out around early to mid May to monitor for the emergence of the
adult flies, which will indicate the time to apply controls to break the cycle
of reinfestation.
- Native holly leafminer mines are very obvious right now on American Holly, but there is nothing to be
done for management. Wait until June to place out yellow sticky cards to monitor
for the next generation of adult flies, and treat at that time with a knockdown
type spray, such as a pyrethroid.
- Birch leafminer -
Yellow sticky cards should now be placed out in susceptible birches where leaf
expansion has begun. Adult sawflies should appear around the time that the leaves
are half-emerged from the buds. Treat when the adults appear.
Gall Formers:
- Eastern
spruce gall adelgid is actively feeding
and about to stimulate new gall formation. In cooler
areas where bud break has not yet begun, oil sprays
at the summer rate can be very effective. Once galls
are formed, managing this pest is extremely difficult.
Norway and white spruce are two common hosts for this pest in MA.
- Cooley
spruce gall adelgid is also active on
blue spruce. Its biology, damage, and management
are very similar to that of eastern spruce gall adelgid.
However, bear in mind that oil sprays do remove the
blue color from blue spruce needles for at least
a few months.
Reported
by Robert Childs, Entomologist, UMass Extension Landscape,
Nursery and Urban Forestry Program, Amherst.
The
rainfall has given plants a good watering, but with leaves
developing, they are vulnerable to leaf spot
and shoot blight infections, especially when accompanied
by temperatures of 50-70 degrees F. This is the time to
apply protective fungicides to nursery and specimen woody
landscape plants.
Rhabdocline needle cast fruiting
structures are visible on infected Douglasfir needles. Symptoms
of Rhabdocline infection appear as elongated red-brown spots
and bands on infected needles. Spots often coalesce, and most
of the needle turns color except for the base, which remains
green. Infection tends to occur on the bottom of the tree first.
Infected needles drop prematurely from now into the summer.
Spores released from these fruiting bodies during cool, wet
weather infect new needles that will soon start developing.
Avoid overhead watering of Douglasfir at this time of the year.
Provide adequate spacing, and limit weed growth around young
trees. Consider fungicide applications to susceptible, high-value
trees if this spring is wet. Maintain protection during the
vulnerable period when the needles are first emerging from
buds until they expand to full size.
Sphaeropsis
(Diplodia) shoot blight on
pine can cause significant damage to stressed red,
pitch, Japanese black and, especially, Austrian pine
in our area. If wet weather continues, new shoots
developing on these trees are vulnerable to infection.
Consider applying fungicides to protect susceptible
trees as soon as buds swell significantly. Reapply
sprays at labeled intervals until the new growth
fully expands, if wet conditions persist. The Sphaeropsis
fungus produces significant amount of inoculum on
the outer scales of second-year cones, as well as
infected shoots and needles. Prune affected shoots
when plants are dry to improve appearance, but this
will make little difference in reducing inoculum
for new infections without cone removal, too. If
replacement of severely affected pines is an option,
plant trees resistant to Sphaeropsis shoot blight
as well as better adapted to grow on the site.
Gymnosporangium rust fruiting
structures are visible on eastern red cedar (really a juniper)
and Rocky mountain juniper, as well as the occasional Chinese,
common, creeping and savin juniper hosts. Specifically, cedar-apple
rust galls
are visible on eastern red cedar (really a juniper) as eruptions
of orange, gelatinous masses protruding from pea- to golf
ball-sized galls. These fruiting structures release spores
that infect apple and crab apple leaves at this time of the
year during cool, rainy periods. Likewise, fruiting structures
of hawthorn rust and quince rust are on many of these junipers,
but the fruiting structures are less conspicuous. Hawthorn
rust develops pea-size or smaller galls while the quince
rust fruiting structures emerge as red-orange 'cracks'
in the bark of infected branches. Leaves, green shoots, and
fruit of serviceberry, hawthorn, mountain ash, quince, flowering
quince, and pear, as well as apple and crabapple are susceptible
broadleaf alternate hosts.
Sycamore, maple, oak, and ash anthracnose are
evident now as dark-green to dark-brown curling leaves and
shootssycamore,
maple, and oak, while ash anthracnose appears as young green leaves with very
tiny brown spots falling from the trees. Anthracnose is widespread on early leaves
and shoots this year due to the abundance of inoculum on overwintering twigs
and fallen leaves, as well as the consistently wet weather. These diseases cause
some premature leaf loss, but that is not going to seriously injure an otherwise
healthy tree. In the fall fine prune infected twigs if practical, as well as
collect and dispose of fallen leaves. Promote drying of foliage by pruning and
spacing plants to increase the penetration of sunlight and air circulation in
and around plants.
Phomopsis
tip blight -
The current wet conditions, along with the development of immature scale-leaves/needles
are favorable for infection of juniper by Phomopsis tip blight. Juniper shoots
that are tan-gray with pinhead sized, black fruiting bodies are producing spores
at this time. New growth that becomes infected this spring with Phomopsis tip
blight will turn green-yellow, then brown and die within a few weeks of infection.
Management begins with the removal and disposal of infected shoot tips when they
are dry to reduce inoculum. Cut an inch or so below the boundary between dead
and healthy tissue. Now is the time to initiate fungicide control of juniper
tip blight to improve plant appearance. Grow junipers in an open, sunny location
to promote drying of foliage, that are adapted to the site and that have resistance
to tip blight.
Dogwood
anthracnose fruiting
structures are apparent on trees where there are buds that
did not open as well as twigs and branches that died back.
Water shortage, heat stress, compacted soil, and winter
damage weakens trees and increases the severity of the
disease. Dogwoods receiving good cultural care are better
able to limit the extent of dogwood anthracnose damage.
Water during dry periods, and maintain two to four inches
of composted bark mulch over as much of the root area as
possible. Prune off and dispose of diseased twigs and branches
to reduce anthracnose inoculum in the tree. High value
trees benefit from four fungicide applications to control
dogwood anthracnose during wet seasons. Begin, as buds break open; reapply when
bracts have fallen, and again four weeks later. A fourth application in late
summer protects flower buds if there is wet weather after they form. If this
is a persistent problem, consider planting one of the many resistant cultivars
of C. florida and C. kousa now commercially available.
Ramorum Blight, also known as Sudden
Oak Death (SOD) -
Since the early 1990's, oaks and tanoaks were dying in the coastal counties
of California. Since then, other types of plants have been found to be infected
or associated with this disease, referred to as Sudden Oak Death, ramorum leaf
blight or ramorum dieback, or by regulation as Phytophthora ramorum.
The first positive identification of the disease was in 1995 on tanoak in Mill
Valley (Marin County), California. Since that time, surveys confirmed Phytophthora
ramorum on various native hosts and nursery plants in several locations
in California, Oregon, Washington, and British Columbia. When nursery surveys
find infected plants, prompt quarantine and/or eradication activities ensue.
Research conducted by the Agriculture Research Service, US Forest Service, universities,
and others is under way to better identify hosts, improve methods of detection,
and develop effective treatments. USDA APHIS currently regulates 84 plants, two
of which are at the genus level (Camellia and Rhododendron).
There are no chemical treatments currently available to eliminate Phytophthora
ramorum from infected plants.
Dan
Gillman, Plant Pathologist, based in the UMass Extension Plant
Diagnostic Lab at UMass, Amherst.
WEEDS
Inspect areas of landscape where new trees or shrubs, especially
those that were field grown, have been planted in the last year.
Look for perennial weeds that may be growing from
the root ball. Canada thistle, mugwort, quackgrass, bindweed. and
horsenettle are some of the possible culprits. Treat will a non-selective
systemic herbicide (ex. glyphosate). Contact herbicides (Sycthe™,
Reward™) will not provide adequate control.
Garlic mustard is flowering and
should be controlled now before seed is produced. Garlic mustard
is a biennial; therefore, control now will also control first-year
seedlings and second-year plants before they go to seed. A non-selective
translocation or contract herbicide can be used.
A large number
of winter annuals are being observed
in ornamental beds this spring. At this point the goal should
be removal before seeds are dispersed. If you expect that a large
number of seeds have been set, wait until late summer to mulch
and/or apply a preemergence herbicide.
Randall
Prostak, Weed Specialist, UMass Extension Landscape, Nursery,
and Urban Forestry Program, Amherst.
TURFGRASS
Insects: No
report: Visit the Landscape Message
Archive for previous messages.
Weeds
Germinating crabgrass has been observed in
areas of thin turf and non-turf areas.
Dandelion, violets and ground ivy are
done flowering, and postemergence herbicide applications can
begin now.
Postemergence herbicide combinations that contain
triclopyr should be use for wild violets. Spring
treatment will usually not provided complete control with one
application. Retreat at first sign of regrowth, or accept partial
control for the time being and retreat in September.
Randall
Prostak, Weed Specialist, UMass Extension Landscape, Nursery,
and Urban Forestry Program, Amherst.
2006 UMass Green School to Start October 31 in Milford,
MA
Green School is a comprehensive certificate training program
for Green Industry professionals taught by UMass Extension Educators
and Faculty. This course is designed for landscape, turf, and
other horticultural practitioners wishing to gain an understanding
of horticulture fundamentals and strategies and their relation
to environmental quality. Green School attendees learn about
sustainable approaches to turf and landscape management in managed
environments. Green School's curriculum is based on research
and information emphasizing environmental stewardship and integrated
pest management (IPM). Participants develop an understanding
of how proper management practices impact natural resources such
as soil and water. Participants learn to make environmentally
appropriate decisions related to turf and plant selection, plant
maintenance, pest and nutrient management.
The 2006 schedule and
application form will be posted on www.umassgreenfino.org in
June.
Scouting for Pests and Problems of Turf and Woody Ornamentals,
5:00-7:00 p.m.
May 30, 2006 - Springfield, MA
June 1, 2006 - Wellesley, MA
June 15, 2006 - Bridgewater, MA
Learn how to put IPM practices to work efficiently. Join
us in a walk through the landscape for demonstrations of IPM tools
and techniques, as well as a close look at some of the most common
cultural problems and troublesome insect, mite, and disease problems.
Workshop held rain or shine. Two Pesticide contact hours for
categories 29, 36, 37, and Applicators License available.ISA,
MCA, MCH, and MCLP credit requested. See our Conferences & Workshops
page for registration information.
July 19, 2006 - Nursey
& Landscape Summer Meeting & Trade Show - The
day will offer horticulture education workshops presented by
well known researchers and educators, a trade show and hands-on
insect, disease, and weed laboratory. At press time, plans were
underway to feature an actual outdoor set-up of garden center
displays showing examples of today’s most successful marketing and
plant branding strategies. Plans to organize class reunions for
Stockbridge School of Agriculture and UMass alumni the day before
and have University Admission officials on hand to answer questions
about student applications are also in discussion.
This special
event will also showcase
Dr. Michael A Dirr, respected author, lecturer and retired Professor of Ornamental
Horticulture from the University of Georgia, Athens as keynote speaker. Dr. Dirr
will give a presentation on Breeding, Evaluating, Introducing
and Marketing New Woody Plants. Professor Dirr has had a long
and varied career since he received his Ph.D. in Plant Physiology
from the University of Massachusetts, Amherst, in 1972. Before
moving to Georgia he held appointments at the University of Massachusetts,
the University of Illinois, Urbana, and the Arnold Arboretum
of Harvard University.
You
will want to mark your calendars now. For more information, go
to http://www.mnla.com
, http://www.umassgreeninfo.org,
or contact UMass Extension’s Landscape, Nursery and Urban
Forestry Program at (413) 545-0895, eweeks@umext.umass.edu. Time: 9
AM to 3:00 p.m. Location: UMass Amherst Student Union and Metawampe
Park.
IMPORTANT
INFORMATIONAL RESOURCES
2006 UMass Extension Green Directory: Now Available!
The 2006 UMass Extension Green Directory is a comprehensive guide
to educational resources for Massachusetts Agriculture industry
professionals. This 25 page guide is used as a reference document
all year long! To receive a copy, send mailing address: email
greeninfo@umext.umass.edu;
fax requests to 413-577-1620. The complete directory is also available
online in PDF format. Visit http://www.umass.edu/agland
and click 'The Green Directory' link in the right hand menu.
Two UMass Extension Web Sites are specially
designed to provide Green Industry professionals with resources,
upcoming educational programs and events, and other relevant information.
The Internet address for the Landscape, Nursery, and Urban Forestry
Program is http://www.umassgreeninfo.org.
The Turf Program address is http://www.umassturf.org
.
Don't forget to visit the UMass
Extension Online Weed Herbarium!
The freshly revised 2006-2007 Professional
Guide for IPM in Turf for Massachusetts features
the latest techniques critical to environmentally sensitive,
integrated management of lawns, athletic fields, and golf courses.
The guide, intended for use by professionals, presents research-based
material regarding turfgrass selection and water conservation,
as well as current approaches for managing disease, insect,
weed, and nematode problems. Municipal and school officials
charged with establishing IPM programs in their communities
and gardeners and homeowners serious about sensibly caring
for their properties will find unique and critical information
in the guide as well.
The 2006-2007 Professional
Guide can be used effectively in a wide range of management schemes:
from organic, to low-maintenance, to high-intensity care of high-use
turf. Alternative and cultural pest control options are highlighted,
and pesticide selection advice is based on least environmental
impact. While certain portions of the guide are specific to Massachusetts,
much of the information is applicable throughout New England.
Initially developed in 1991, this revision for 2006-2007 marks
the 8th edition of this popular publication.
To obtain a copy,
order online from the Outreach Bookstore (http://umassoutreachbookstore.com );
or call the UMass Outreach Bookstore. The phone number is (413)
545-2717. In either case, payment may be made by credit card.
Alternatively, you may visit the UMass Outreach Bookstore during
normal business hours; Monday through Thursday from 9AM-3PM,
closed Friday. The bookstore is located in Draper Hall on the UMass
campus.
UMass Extension’s Turf Management Guide
and IPM Facts: For more information about the turf pests
mentioned in this message, you will need to refer to the following
publications: the freshly revised Professional
Guide for IPM in Turf for Massachusetts, 2006-2007
edition and Turf
IPM Facts .
Call (413) 545-2717 to order these publications from the UMASS
Outreach Bookstore 
DIAGNOSTIC
SERVICES
UMass Laboratory Diagnoses for Turf and
Landscape Problems - Accurate
diagnosis for a turf or landscape problem can often eliminate or
reduce the need for pesticide use. The UMass Extension Plant Diagnostic
Lab is available to serve commercial landscape contractors, turf
managers, arborists, nurseries and other green industry professionals.
It provides woody plant and turf disease analysis, woody plant
and turf insect identification, turfgrass identification, weed
identification, and offers a report of pest management strategies
that are research based, economically sound and environmentally
appropriate for the situation. Send specimens and payment (payable
to the University of Massachusetts) to UMass Extension Plant Diagnostic
Lab, Holdsworth Natural Resources Center, 160 Holdsworth Way, UMass,
Amherst, MA 01003. The fee for a woody plant disease analysis is
$50; the fee for turf disease analysis or nematode assay is $75.
All insect, weed and turfgrass identification samples are $25 each.
For more detailed submission instructions see http://www.umass.edu/agland/diagnostics 
NEXT UPDATE: The next issue will be available
on Friday, June 2, 2006.
This
message is produced by the UMASS Extension, Landscape, Nursery
and Urban Forestry Program. The copy is prepared by Anna Greene
from data and reports provided by the staff and faculty of the
UMass Landscape, Nursery and Urban Forestry Program and the UMASS
Extension Turf Program as well as cooperating horticulturists
and Green Industry professionals. The text is adapted for access
via the internet by Jason Lanier and made available to subscribers
via electronic transmittal by Ellen Weeks.
DISCLAIMER.
This message is intended for commercial use. UMass Extension assumes no liability
for recommendations. It is the responsibility of the applicator to verify the
registration status of any pesticide BEFORE applying it. Different states have
different regulations as well. The use of trade names (*) does not imply endorsement.
Similarly, there may be other products you prefer to use.
Comments
or suggestions in regard to the Landscape Message? Please e-mail
the webmaster.
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