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Garland, Dill Talk about Pest Management on WVII

University of Maine Cooperative Extension’s pest management specialist James Dill and horticulturist Kate Garland spoke with WVII (Channel 7) for the latest installment of its “Backyard Gardener” series. Garland and Dill gave tips on management of beetles.

Press Herald Interviews Handley, Kirby on Garden Insects

The Portland Press Herald spoke with David Handley, a vegetable and small-fruit specialist with the University of Maine Cooperative Extension in Monmouth, and Clay Kirby, an insect diagnostician with the UMaine Cooperative Extension in Orono, about bugs in the garden. The pair spoke about this season’s likely pests.

Brown Marmorated Stink Bug Alert

a Brown Marmorated Stink Bug (BMSB) adult, with labels pointing out the rounded shoulders it has, as well as the white bands that it has on the antennae -- the white bands stretch across the gap between the two outermost segments of the antennae A live specimen of Brown Marmorated Stink Bug (often abbreviated as BMSB) was captured in Old Town on Wednesday, February 27th, 2013 (specimen is pictured here at right). Its scientific name is: Halyomorpha halys (Stal).

Detailed Fact Sheet: Brown Marmorated Stink Bug (Northeastern IPM Center) (includes a page that will assist you with correct identification:

BMSB — same photo as above, but without any labeling

Late Blight News

Late Blight Photos / Symptoms

Late blight has very recently been reported in potato plantings in coastal Maine (Woolwich, in Sagadahoc County) and an additional outbreak was reported in Penobscot County. Late blight has also been reported in the St. Andre area of New Brunswick, Canada. Conditions for the development of late blight have been very good in Maine and growers should be on the alert to catch any early symptoms on their plants and be ready to apply appropriate control measures. Typical symptoms will be water-soaked lesions on the leaves with fine, white cottony mycelium on the undersides. Infections on the stems appear as dark, almost black lesions.

Late blight spores can travel over 40 miles under the right conditions (wet and warm) and the spread can be very fast. We are encouraging all growers to carefully and regularly inspect their plants for this disease. Please report any suspicious symptoms to us at our UMaine Extension Pest Management Office at 207-581-3883 or 1-800-287-0279 (in Maine). Samples should be sent in a sealed plastic bag with a dry paper towel to keep them fresh. Visit for more detailed shipping and sample preparation directions, as well as a submission form for any samples you send to us.

More information about Late Blight:


European Chafers

European Chafer beetles are now active in the Bangor region of the state (and have likely been out for a little while already in areas south of Bangor).  The adult is a 1/2 inch long, golden tan to light brown, oval-shaped June beetle [photo courtesy of USDA ARS].  These beetles emerge from the ground annually at this time of year (June & July), just as it is getting dark, and take off in search of eligible mates.  Females begin laying eggs (in the soil) just a day after mating, and the eggs hatch in 2 to 3 weeks into tiny white grubs–the destructive stage of this pest–which begin feeding right away on grass roots.  The grubs continue to feed on the roots of grasses throughout the summer and again the following spring, chewing them off and killing the grass in the process.  So if you are seeing these beetles swarming in your area, and/or you have areas of turf that have been victimized in the past by this pest, now is the time to be preparing to take control measures, if that is on your agenda!

Detailed Fact Sheets: European Chafer (Purdue) – see also pdf (Cornell), and for more about the grub stage of this and other similar lawn and turf pest beetles, visit: White Grubs in Lawns (University of Illinois) and White Grubs in Home Lawns / pdf (Penn State)

Rose Chafers are also active now.

Eastern Tent Caterpillars

The silken/webbed nests spun by Eastern Tent Caterpillars are starting to be seen in trees now (early May).  These caterpillars feed on apple, peach, plum, crabapple and cherry trees and build distinctive nests in the forks of the branches. Feel free to review our fact sheet on these caterpillars for more information, including some things you can do to combat them (and how they differ from Forest Tent Caterpillars).

Additional Photos:

an EasternTentCaterpillar and an example of the communal nests they make in trees Eastern Tent Caterpillar - egg masses

Beetles and Grubs and Ticks, Oh My!

Spring is well underway, and here are some of the things getting some attention as of late:

  • Predaceous Diving Beetles: These beetles, in a family of water beetles called Dytiscidae–based on the Greek dytikos, meaning “able to dive” [in water]–are out and about now, and being noticed by some homeowners. They are nothing to be concerned about, however, and you can find them in the ‘Curiosities’ group of our Fact Sheets section, as they are indeed a source of curiosity for many people.  They show up sometimes in swimming pools, or in driveways or parking lots where it is suspected that they mistake the shiny surface of many automobiles for bodies of water, as is their natural habitat (i.e. they are aquatic, and have structural modifications ideal for swimming). When in water, they move their hind legs together like oars. Backswimmers also swim this way, but other aquatic beetles move their two back legs one at a time when swimming.  As their name implies, these beetles prey on other insects and critters–such as tadpoles–small enough for them to overpower with their short, but sharp, mandibles. The larvae (which stay in the water) are also predaceous, and are commonly known as water tigers (photo of larval stage).

a Predaceous Diving Beetle a Predaceous Diving Beetle a Predaceous Diving Beetle

Above: Some Predaceous Diving Beetles found in Maine.  Most Predaceous Diving Beetles are dark brown, blackish or dark olive in color. Some have golden highlights such as the one shown above (far-right).

  • White Grubs: We are getting a lot of white grubs brought in to our office for identification, the vast majority of which thus far this season are the European Chafer [MSU provides an excellent fact sheet on this critter and we are linking to theirs until we can add the finishing touches to one of our own].  Our insect diagnostician says he is seeing evidence of their feeding damage to grass in peoples’ lawns, cemeteries, etc. in the Orono & Old Town, and Bangor & Brewer areas now.  It seems that the European Chafer has had several profitable seasons in a row, and it may take an especially harsh (i.e. COLD) winter before we begin to see their numbers decline.  As it stands now, this pest seems to be on the rise, unfortunately.

May is Lyme Disease Awareness Month in Maine!! Know Ticks, No Lyme

[Text courtesy of the Maine CDC]: Lyme disease is the most common vector-borne disease in Maine.  May is Lyme Disease Awareness Month in Maine, so remember to do your tick checks!  With the mild winter, it is never too early to start thinking about tick prevention.

a deer tick (non-engorged) next to a US penny for scale purposes

Unengorged Deer Tick (also called Black-legged Tick) (UMaine Extension photo)

Lyme disease is a bacterial infection that is carried by Ixodes scapularis (the deer tick).  Maine had a record high number of cases in 2011, with positives occurring in all 16 counties.  Lyme disease is most common among school-aged children and middle-aged adults.  As the weather begins to get warmer, more ticks will be out in the open.  Most Lyme disease infections in Maine occur during the summer months.

Note from UMaine Extension: Visit the Ticks page of our Home & Garden IPM website for more tick photos (including pictures of other kinds of ticks):

The most common early symptom of Lyme disease is an expanding red rash that occurs 3 – 30 days after being bitten.  Fever, joint, and muscle pains may also occur.  Lyme disease is treatable, and the majority of patients recover after receiving appropriate therapy.

Lyme disease is a preventable illness.  Maine CDC recommends following the “No Ticks 4 ME” approach which includes:

1.    Wear protective clothing
2.    Use an EPA registered repellent:
3.    Perform daily tick checks
4.    Use caution in tick habitats

Ticks must be attached for at least 24 hours for the bacteria that causes Lyme disease to be transmitted, so prompt removal of ticks is extremely important.  Anyone with a known tick bite, or who spends time in a tick habitat, should watch for symptoms for at least 30 days after exposure.  If symptoms develop, call your healthcare provider.

Additional information:
Maine CDC has numerous educational materials available online at


Tar Spot Fungus

Tar Spot fungus on a maple leaf (click for a magnified view) (additional images below)

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As you may have noticed, many of the maple trees in the area developed unsightly black leaf spots over the course of the 2011 summer and foliage was turning brown and dropping rapidly.  The combination of the fungal pathogens ‘tar spot’ and ‘anthracnose’ caused this aesthetic damage to maples throughout Maine.

Tar spots, as the name suggests, are raised, black spots that form on the upper surfaces of maple leaves, not as the result of contact with actual tar, but due to a fungal infection.  Fungi from the genus Rhytisma, most commonly Rhytisma Acerinum, typically shows up on maples in late spring or early summer as light green or pale yellow spots.  As the season progresses, the yellow color intensifies and raised, black tar-like spots are formed within the yellow spots.

Tar spot alone is rarely serious enough to be detrimental to the overall health of infected trees.  However, as the infection progresses trees become unsightly and can experience premature defoliation.  If infected maple leaves begin to crinkle and turn brown, anthracnose, another common disease of maple, may also be present.

The fungi that cause tar spots and anthracnose overwinter on infected leaves that fall to the ground.  The following spring, the fungi produce spores which are carried by the wind and can re-infect susceptible foliage at bud break, if weather conditions are right.  The most effective management strategy is to rake and destroy infected leaves in the fall, thus reducing the amount of overwintering fungi.  The application of fungicides to control tar spot is typically not recommended because complete coverage of all infected leaf surfaces is necessary and can be extremely difficult as well as costly.

James F. Dill & Griffin M. Dill

early stage of Tar Spot fungus infection on a maple leaf Tar Spot fungal infection - pustules starting on a maple leaf Tar Spot fungus - coalescing stage on a maple leaf Tar Spot - coalescing advanced Tar Spot fungus - advanced stage Tar Spot (outdoors - showing leaves that have dropped, which is a side effect or result of the infection)

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Late Blight News and Confirmations

Late Blight Photos / Symptoms

August 17th, 2011: The Maine Public Broadcasting Network Monday interviewed UMaine Cooperative Extension pest management specialist Jim Dill about new reports of late blight affecting potato plants in Aroostook, Kennebec and Androscoggin counties and tomatoes in Maine’s Mid-Coast areas. Damp, overcast weather helps spread spores from the fungus, which can devastate certain crops in a matter of days.

July 22nd, 2011 [Potato Update]: Potato late blight was found in one location in Central Aroostook County.  The infection was in the upper portion of the plants, indicating that the infection was the result of wind-blown spores.  Late blight has also been reported in Denmark, New Brunswick.

July 5th, 2011: The following states confirmed late blight (so be on the lookout): Maine, Michigan, Connecticut, Florida, New York, Delaware and Virginia. Conditions for the development of late blight have been very good in Maine and gardeners and farmers alike should be on the alert to catch any early symptoms on their tomato and/or potato plants.   Typical symptoms will be water-soaked lesions on the leaves with fine, white cottony mycelium on the undersides.  Infections on the stems appear as dark, almost black lesions.

More information about late blight:

Spring 2011

Late May Observation: Eastern Tent caterpillars have begun appearing in trees, along with their familiar communal tents. The young caterpillars feed on the buds, and the nests become apparent this time of year. As the larvae grow they begin to feed on leaves. When the population increases, it is not uncommon for trees and forests to be defoliated. The caterpillars mature in the first part of June, with adult moths appearing during the last part of the month, when egg-laying takes place. There is one generation per year.

The beginning of the spring brought large numbers of low-flying, solitary ground-nesting bees over many Maine lawns and flower beds.  These beneficial insects are good pollinators that are helping to fill the honey bee gap.  They are not particularly aggressive and their numbers will lessen as spring turns into summer.

Most of the white grubs that have been coming into our lab this spring from the Brewer, Old Town, Orono, and the Bangor area are European chafer grubs.  This species of white grub starts feeding earlier in the spring, feeds more aggressively, and feeds later into the fall, than the other species in the area.  The European chafer grubs have been quite plentiful in this area for the last three years.  Those desiring an organic approach for the management of the next generation of white grubs, may consider using beneficial nematodes, best applied during the last three weeks of August.  Preventive measures targeting the next generation of grubs, using conventional materials, would generally work best when applied in June and July.  Before using pesticides on your lawn, one should be knowledgeable about soil type and ground water protection and surface runoff patterns which may affect lakes, ponds, rivers and streams.

Once the weather warms and dries up we should have good numbers of black flies, especially near streams and rivers.  It should be noted that black fly populations are not always evenly distributed, but can be in localized dense swarms.   Personal protective tactics, such as limiting exposed skin and the use of repellents, are suggested for those involved in outdoor activities in high black fly areas.

We have had a number of deer ticks brought into the tick lab starting in April.  Please be sure to do tick checks after hiking, gardening, walking the dog, and other outdoor activities that may take you into the forest or brushy areas.

a deer tick (non-engorged) next to a US penny for scale purposes photo of a deer tick next to a dog tick (both are unfed or non-engorged, and both are beside a US penny for relative size comparisons)

Clay Kirby
Insect Diagnostician

cartoon bug reporter