Forest & Shade Tree – Insect & Disease Conditions for Maine October 9, 2024

Forest & Shade Tree – Insect & Disease Conditions for Maine October 9, 2024

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Maine Forest Service

Forest & Shade Tree – Insect & Disease Conditions for Maine

October 9, 2024


In this Edition:


Insects

American Dagger Moth (Acronicta americana)

This caterpillar is a common sight in late summer in Eastern North America. Resembling tussock moth caterpillars but part of a different family (Noctuidae), these caterpillars can be found in a variety of different habitats, most commonly around wooded areas where their preferred host trees grow as well as lower lying swampy areas. Caterpillars of this species can be found July through September. The host range is broad and includes alder, ash, birch, elm, hickory, maple, oak, poplar, walnut, and willow as well as other hardwood trees. These caterpillars have a shiny black head and are covered in white or yellowish hairs. Four separate bundles of long black hairs are towards their head (anterior), and a single bundle of similar hairs is at the rear (posterior). This species overwinters as a pupa inside a silken cocoon in a sheltered place, with the adults emerging in May and being active until August in Maine. Although not closely related to tussock moths, the caterpillar’s hairs can cause irritation in some people.

A fuzzy yellow caterpillar with black spikes

Image: American Dagger moth caterpillar on a driveway.

Browntail moth (Euproctis chrysorrhoea)

As noted in the August conditions report, the distribution of the browntail caterpillar population in Maine appears to be more sporadic compared to previous years. This was likely due to the pathogens that attack browntail caterpillars, which were helped by the wet spring and summer last year and a more “normal” precipitation regime this spring and early summer.

Early leaf senescence due to the dry conditions has hampered the ability to see some of the skeletonization damage from the young caterpillars during our aerial surveys. Our early summer aerial surveys this past year only turned up around 2,000 acres of defoliation, which is down quite a bit from previous years. We recommend being vigilant and doing your own dooryard survey on a sunny day during the winter once the leaves are off the trees. This will help prevent unwelcome surprises in the spring, guide management decisions and let you know where to focus treatment if browntail is still present in your area.

Learn more about the risks of exposure to browntail caterpillar hairs and management this time of year in our browntail moth bulletin from August.

Emerald Ash Borer (Agrilus planipennis)

Insects stuck to a purple background

Image: Two adult EAB beetles (circled in yellow) recovered from a purple prism trap in the Waterville area in late September 2024.

As we near the end of our purple prism trap monitoring program for 2024 and traps have been checked for the final time, five of the traps in our statewide network have proven positive for adult EAB beetles. This marks the first time in several seasons since any PPT has captured an actual beetle. Along the western border of Maine, this includes two traps near the Andover infestation first reported in March 2023. In central Maine, this includes a trap near the Waterville infestation area, first reported in May 2023. Both finds are in areas already regulated for EAB.

In northern Maine, two positive traps have been identified outside of regulated areas in Westmanland and Caribou. These new infested areas prompt the addition of approximately a two-town buffer around the predicted expansion area surrounding these detections (see map). If you have feedback on this change, please feel free to reach out to foresthealth@maine.gov or horticulture@maine.gov. Please note that our other survey efforts for emerald ash borer are continuous, and additional changes may result from those activities.

Map of Maine showing areas with emerald ash borer

Image: Updated EAB regulatory map with new additions (purple) in northern Maine resulting from positive PPTs found outside the extents of the previous regulated area during the 2024 season.

Also in southern Maine, EAB has been reported for the first time in Sagadahoc County by the Bath City Arborist and confirmed by MFS staff. Although this is a first county record, it is only a short distance of about four miles away from a previously known infested area in neighboring Brunswick in Cumberland County. In anticipation of this arrival, all of Sagadahoc County was already located within Maine’s EAB regulated areas prior to the detection. The Lincoln County line is also just a short distance up Route 1, so residents in the Wiscasset area are encouraged to report any ash trees they suspect may have EAB in that area to MFS.

Many are aware of the extensive efforts by MFS staff to establish biological control agents for EAB here in Maine. Although these parasitoids come from the native range of EAB in Asia, it’s important to note that there are some parasitoid species native to North America that will also attack and kill EAB larvae. This was a welcomed sight when inspecting the infested tree removed in Bath, as well as working on another project recently in the Waterville area. Even though only a small amount of bark was removed from these trees to look for EAB larvae, ample evidence of parasitoids presumed to be in the genus Atanycolus was readily observed in both locations. MFS staff plans to collect some of these parasitoid pupae for genetic identification and attempt to rear some to adulthood for morphological identification in 2025.

Two photos of larvae in wood

Images: (left) Three solitary parasitoid pupae found in emerald ash borer larval galleries within an infested ash tree removed in Bath in September 2024; (right) A solitary parasitoid larva actively feeding on an emerald ash borer larva within an infested tree in Waterville in September 2024.

Ash Preservation Project – Year One Update

The first year of the ash preservation project is now completed, with insecticide treatments successfully administered at three different sites in southern Maine. This project, launched to safeguard ash trees from the invasive emerald ash borer (EAB), focuses on the long-term conservation of healthy trees across the state. This approach aims to not only protect individual trees, but also preserve the genetic diversity and cultural significance of Maine’s ash population.

Twelve ash trees were injected with a systemic insecticide to protect them from EAB for up to three years at each of this year’s selected sites in Scarborough, Falmouth, and Georgetown. The work doesn’t end here; MFS plans to revisit these trees to monitor their health and reapply treatments over the coming years. These trees represent the first step in an intended network of protected ash trees across the state. This network will act as a refugium, ensuring that even as EAB continues to spread, certain pockets of Maine’s ash population will remain on the landscape, from which valuable seeds can be collected.

Collaboration has been key to the project’s success. We greatly appreciate the cooperation of our partners in finding suitable locations to establish these important preservation sites. Stay tuned for more updates as we continue to expand the network with the help of local landowners, land trusts, and other land managers.

A person and a tree trunk

Images: (left) A mature ash tree is injected with an insecticide containing the active ingredient emamectin benzoate; (right) a tag indicating the tree has been treated for emerald ash borer.

Hemlock Woolly Adelgid (Adelges tsugae)

As I write this, hemlock woolly adelgid (HWA) nymphs are about to emerge from their period of aestivation (summer dormancy) and will soon start to feed, grow, and produce their typical white woolly waxy covering. Because eggs or crawlers are not present, and the new wool is fresh and obvious, late fall or early winter is an excellent time to monitor for HWA presence.

Where and how should you monitor for HWA? The simplest answer is to flip over recent-growth twigs and look at the undersides for the white fuzzy ovisacs (the ‘wool’) any time you walk through hemlocks. Crawlers are often transported to hemlocks by birds, animals, humans, vehicles or wind. Therefore, you may be more likely to find HWA on the edges of the forest, such as along rivers, roads, trails, and edges of fields. In addition, hemlocks on edges often have fuller crowns and branches lower to the ground which are easier to examine.

One location we are very rarely able to examine is the upper branches of trees. There have been multiple occasions where we have surveyed for HWA in the understory and found nothing, but then found a small infestation in the crown of a fallen tree. If you are a forester, landowner, or land manager with a hemlock stand in the green stippled area of the map below, and you plan on cutting, please consider letting us know. We would be interested in coming out after harvest and surveying the slash for HWA. You can email Colleen.Teerling@maine.gov or call 287-2431 or 287-3096 if you are interested in this.

Map of Maine showing areas with hemlock woolly adelgid

A person next to a fallen tree in the woods

Image: Hemlock woolly adelgid was found on this downed hemlock even though none had been seen in a thorough survey of the understory.

Orange-humped mapleworm (Symmerista leucitys)

A black and orange striped larva on a twig

Image: An orange-humped mapleworm explores a sugar maple tree in northern Maine (Somerset county). Caterpillars in the late season can be identified by looking for an orange head, an orange hump near their rear, and three black lines that run down their bodies with white-gray separating the lines.

Despite the name, the orange-humped mapleworm is not actually a worm – instead, it is a native caterpillar species that can be found chewing on a variety of deciduous hosts in the late summer. These caterpillars prefer to feed on maple and beech trees, but they are not considered a forest health concern. Since these caterpillars are late season defoliators, the leaves they are eating are at the final stage of their development and will not cause serious injury to the trees. Caterpillars will continue defoliating through September and overwinter as pupae in the leaf litter layer until they emerge in the spring.

Defoliation from this species is cyclical, where a couple years will have localized outbreaks of high populations and heavy defoliation, followed by years with little to no caterpillar populations. In 1956, orange-humped mapleworm was the cause of roughly 23,500 acres of defoliation in northern and central Maine. The state did not have another outbreak until 1986 through 1990 when the caterpillar defoliated sugar maples and beeches in central and eastern Maine alongside the variable oakleaf caterpillar (Lochmaeus manteo). Since then, there have not been any similar defoliation events from orange-humped mapleworm caterpillars. Management for orange-humped mapleworm is typically not necessary as this native species is often kept in check by our native predators and their feeding occurs at the end of the growing season.

Tussock Moths

The following three species are not technically “Tussock moths” as their common names suggest. That title is reserved for members of a subfamily within Erebidae called Lymantriinae. This subfamily includes spongy moth, browntail moth and white marked tussock moth mentioned in this conditions report. These three species are native and belong to different subfamily called Arctiinae.

Banded/Pale Tussock Moth (Halysidota tessellaris)

This is a relatively common species found east of the Rocky Mountains with the caterpillars being found July to October. They are variable and can be whitish tan to yellowish green to almost brown (see photo above). The caterpillars have long paired white and black bundles of hairs on the second and third body segments with the bundles on the third segment pointed towards the head. There is a third set of long hairs towards the posterior end (rear). Recorded host plants include alder, ash, birches, elm, hazel, hickory, oaks, poplar, tulip tree, walnut and willows. Adults fly from May to August and have one generation per year in the north.

Two fuzzy yellow caterpillars on a leaf

Image: Two pale tussock moth caterpillars found in situ showing the color variation of this species.

Spotted Tussock Moth (Lophocampa maculata)

Less commonly encountered than some of the other species mentioned in this conditions report, these attractive caterpillars are black at both ends, yellow or orange in the middle with numerous long, thin white hairs protruding from the black segments at the ends. The yellow-colored segments in the middle have black markings in the center of each segment. The range of this species covers southern Canada the northern U.S., west of the Rocky Mountains, and in the east, south to North Carolina. Caterpillars can be found from July through September on poplar and willow trees however other recorded hosts include alder, basswood, birch, maples and oaks. This species overwinters in a hairy cocoon as a pupa with adult moths appearing in May-July.

A fuzzy yellow caterpillar with black spots on a leaf

Image: A spotted tussock moth caterpillar resting on a leaf.

Hickory Tussock Moth (Lophocampa caryae)

During the past month, we have had several calls reporting hickory tussock moth caterpillars. Like many of our hairy caterpillars, this species can cause rashes in people and generally gets the most publicity. Although they can be locally abundant in certain years, management is generally not necessary as they are native, have their own population controls, and generally don’t cause large amounts of defoliation. The caterpillars are hairy and mostly white with black markings and have bundles of long black hairs on the first and seventh body segments.This species is most common in the eastern U.S. and eastern Canada; however, it can also be found in the southwestern U.S. Caterpillars can be found July through September and, contrary to their common name, have a wide host range which includes ash, oak, hickory, maple and elm; also vines and bushes such as hops, Virginia creeper, raspberry, rose, sumac, and blueberry. Caterpillars feed gregariously until they are nearly full grown, after which they begin wandering. This is when most people encounter them. After overwintering in a hairy cocoon in a sheltered place, adults emerge in May and can also be encountered in June at lights.

A fuzzy white caterpillar with black dots and spikes on a leaf

Image: Hickory tussock moth caterpillar resting on a leaf.

White-marked tussock moth (A true tussock moth) (Orgyia leucostigma)

The native, white-marked true tussock moth caterpillar is fairly common at the end of summer and can be seen on a number of both deciduous and coniferous hosts. White-marked tussocks are classified in the genus “orgyia”, which is a Greek word meaning “outstretched arms” due to the distinctive black hairs that extend past their bodies from both ends. This species shares the same subfamily with browntail moth (Euproctis chrysorrhoea), Lymantriinae, which consists of caterpillars with tufts of hairs (tussocks) on their back that can be irritating to humans. Although white-marked tussock moth caterpillars also have red-orange glands on their backs like browntail moth caterpillars, their hairs do not have a chemical toxin that browntail moth caterpillars have.

Caterpillars pupate into sexually dimorphic adult moths, where adult female moths are wingless and attract males solely using chemicals known as pheromones to communicate. After mating, eggs are often laid on the host trees in late September, where they will remain until they hatch as caterpillars next spring. Since these caterpillars are a native species, we have native diseases and predators that can usually keep their populations from becoming a forest health concern. On occasion, heavy infestations of this species can fully defoliate host trees with local outbreaks on maple, oak, elm, spruce, and a variety of fruit trees but management is typically not necessary.

A black caterpillar with yellow stripes and white tufts on a leaf

Image: White-marked tussock moth caterpillars are hairy and distinctive with a red head, four vertical tufts of white hair, two red-orange glands, and black tufts of hair in the front and back of their bodies. This caterpillar enjoys a maple leaf in Alton (Penobscot county).


Diseases and Environmental Issues

Beech leaf disease

Continued reports of beech leaf disease (BLD) through late summer and into early fall have revealed more towns where the disease is present. As can be seen in the BLD Dashboard figure below, BLD has been found in a total of 176 Maine towns, with 79 of those new towns reported this year. The only remaining county where BLD has not been found is Franklin County.

Screenshot of the beech leaf disease dashboard website

Image: The MFS BLD Dashboard as of 9/25/2024. This is a tool developed by MFS to track BLD presence/absence data in Maine.

In cooperation with Maine’s Inland Fisheries and Wildlife (IFW), the Greater Augusta Utility District (GAUD), and the public, MFS was able to macroinject Arbotect 20-S into 9 beech trees at 6 sites. IFW offered two sites with clean beech (beech with demonstrated resistance to beech bark disease), GAUD offered one site with clean beech and the public offered sites with clean beech and beech with symptoms, which will offer comparison of the effectiveness of the application. We are eager to see the results of the treatments after leaf-out in spring/early summer. In recent communication with Bartlett Tree Expert’s Laboratories, who have trialed this treatment in past years, the treatment should yield excellent symptom reduction that should last for two years. While Arbotect 20-S injection is not practical for addressing BLD on a landscape scale, it does represent a management tool for high-value landscape trees.

A bucket next to a tree

Image: Macroinjection of Arbotect 20-S into a clean beech on Greater Augusta Utility District land, Augusta, ME.

Dutch elm disease (Ophiostoma ulmi, O. novo-ulmi)

Effects of Dutch elm disease on elms across Maine continued to be reported into September. This seems to be unusually late compared to other years and may indicate that the life cycle (pathosystem) of this disease is changing – the reasons for this are unclear. A recent request for assistance with failing elm plantings was addressed in Skowhegan. Two Ulmus americana ‘Princeton’ elm trees were planted in two locations about 150 yards away from each other. The trees were showing severe symptoms of crown dieback, but had otherwise been growing vigorously in the four years since planting. The Princeton elm cultivar is a pure American elm with a good level of resistance – many of the DED-resistant elm cultivars are cross-bred with Asian or Siberian elms, which have greater genetic resistance to infection by the fungus that causes DED.

It is not clear why these two elm trees became infected. The trees seemed well established, well cared for, and were growing well. However, there was clear evidence of other native elm trees in the surrounding landscape that were currently infected or had died from DED in previous years. Thus, the disease pressure in the area was high. This is a good example highlighting the meaning of ‘resistance’ in the context of tree health. Resistance does not equate to immunity. Although not apparent in this case with the infected Princeton elms, sometimes resistance is closely related to tree vigor, which is, in turn, reliant on resources tied to site factors and tree care.

Two photos of elm trees that have lost leaves

Images: Two different Princeton elms infected with Dutch elm disease in early September, Kennebec County.

Early senescence and fall coloration

In many parts of Maine, autumn coloration seems to have developed a bit ahead of schedule. It is not unusual to see the early fall colors, even in the first half of September in areas where trees experience stress, like wetter areas where eastern larch and red maple often grow. Already in mid-September, and as far south as York County, early coloration was apparent, primarily in red maples and some oaks. This is a deviation from the typical north-to-south pattern of fall foliage color. The reason for this is not clear and does not seem to be attributable to a stressful growing season, as in some recent past years. Despite the dry moths of August and September, the overall 2024 growing season has been mostly positive for tree health and has led to the development of vibrant fall foliage.

Fall Conifers Shedding Older Leaves and Needles

Unlike broad-leafed trees (deciduous trees), most conifers do not completely re-foliate each year (exceptions being native and exotic larches and the less commonly planted dawn redwoods, baldcypress and Pseudolarix spp.). Seasonal needle drop in coniferous trees is a way for trees to increase their efficiency. The oldest needles, those found on twigs and branches closest to the interior of the tree, are shed because they represent a greater energy cost in terms of maintenance and defense than they generate through photosynthesis compared to newer foliage. The energy that the tree saves by shedding inefficient needles is invested in growth, maintenance and defense of more valuable tissues.

People are often alarmed this time of year when they notice coniferous tree species shedding pale-yellow to bright-orange needles that drop onto the ground, lawns, cars and driveways. However, unless there are clear signs of injury, fungal cankers, branch swelling, wilting, signs of insect feeding or signs of fungal infection (e.g., black spots or banding on needles/leaves), there is no cause for alarm. This is very likely simply due to the natural phenomenon of seasonal needle drop and not an insect or disease problem. On the other hand, when conifer needles drop earlier in the season, there is greater cause for concern. This could indicate acute stress or high disease incidence caused by conifer needle diseases that have been commonly seen in past years like white pine needle damage and spruce needle casts.

Three photos of pine trees with yellowing needles

Images: (left) White cedar with naturally senescing leaves; (middle); White pine with naturally senescing third- and fourth-year needles; (right) Red pine with naturally senescing third- and fourth-year needles.

Is my apple tree dying!?

This is a question that has been asked of the MFS forest pathologist several times in the past month. During recent travels, all-but-leafless apple and crabapple trees have indeed been noticeable. If your trees are showing this symptom, don’t lose hope and reach for a saw. First, it’s important to take a closer look to determine the reason for the symptom and assess the overall severity of the situation.

Premature leaf drop can happen for a variety (and combination) of reasons. Defoliation could simply be due to the dry weather over the past several weeks triggering early tree senescence. Alternatively, the leaves could have been heavily impacted by fungal leaf diseases – the most common ones in Maine being apple scab and cedar-apple rust, although occasionally frogeye leaf spot and powdery mildew are responsible for foliar damage. Maybe the combination of a fungal leaf disease, coupled with environmental stress is the reason why your apple or crabapple tree looks as it does this year.

If concerned that something more serious is occurring, search for fully formed buds to ensure the tree’s positive health status – you may have to look a little higher up on the tree if buds have been heavily browsed by deer (also a common problem for apple trees in Maine). Scratch the thin bark of a twig with your thumbnail, and if you see green tissue, that area is fine – if the twig is brittle, try another one. In some more severe cases of leaf disease, trees only hold a few leaves at the top of their crowns. This is likely because the top of the crown gets more light and dries out faster, conditions which do not favor fungi. To reduce the chances and severity of early defoliation next year, clean up the fallen leaves as best you can and compost, burn or landfill them. This will reduce the amount of overwintering disease (inoculum) near the tree. Fungicides can also be used to protect apple and crabapple trees before spores are released in spring.

An apple tree in a field

Image: Apple trees that have lost most of their leaves due to a heavy apple scab infection.

Midcoast Highland Drought

In late September we received a couple of reports of tree mortality on the hills in the Midcoast, mostly around the town of Camden. One such area was ground-truthed on October 1 by the staff pathologist and a staff entomologist. Upon arrival to one of the affected areas after a steep climb, several species of trees and shrubs were showing the same desiccated symptoms. Inspecting the plants, no signs of insect or disease agents were seen; however, dried green leaves were observed on some of the trees hinting at a possible cause. Knowing that the area has not received substantial rain for several weeks and observing that the affected areas were mostly on south-facing slopes with thin soils overlying rock, drought was determined as the cause for the symptoms. Some of the trees had pre-formed buds for next year and the twigs were still pliable, indicating that they will likely leaf out next spring. However, some trees and shrubs were brittle and have likely died. An aerial survey of the area will be performed later this month to document the scale of this drought-related mortality.


Invasive Plant Spotlight

Mile-A-Minute Weed (Persicaria perfoliate)

The Maine Natural Areas Program (MNAP) of the Maine Department of Agriculture, Conservation, and Forestry (DACF) encourages the public to report any sightings of the invasive mile-a-minute vine (Persicaria perfoliate), also known as devil’s tearthumb. Mostly seen in gardens due to hitchhiking in nursery pots or greenhouse soil, this vine has the potential to take over several important Maine habitats if not detected and eradicated.

Two pictures of triangle-shaped leaves

Images: (left) Mile-a-minute’s pea-sized fruits that ripen blue and are cradled by the circular stem leaf; (right) The leaf shape of mile-a-minute vine is extremely triangular.

Mile-a-minute is an herbaceous annual vine that is native to Eastern Asia and can grow up to six inches per day. This plant has alternate light-green leaves that are triangular. The vines and underside of the leaves have curved barbs that allow them to climb over trees and other plants for better access to the sun. Another identifying feature is the circular leaves that wrap around stem nodes, called ocrea, where small flowers and pea-sized fruits develop. Fruits ripen to blue and contain a black seed, which can be easily spread to new locations by deer, small mammals, and especially birds. The fruits and seeds can float in water for approximately one week, being spread by streams and rainfall. This invasive plant has a significant potential to invade most of Maine, as it requires an eight-week cold period to flower, and the plant has been spotted and pulled from a few locations already. Mile-a-minute forms dense mats that weaken other plants and cause poor growth due to blocking sunlight, ultimately decreasing native vegetation. The plants can degrade reforestation efforts, forest stands, and invade most disturbed areas. Mile-a-minute can be found growing in wet or dry soils, allowing it to invade many habitats in Maine.

Other vines in Maine may look similar to mile-a-minute, so be sure to identify the ocrea (the curved barbs along the stems) and the very triangular leaves. Some look-alikes include commonly found native and non-native bindweeds, and native tearthumbs such as arrow-leaved tearthumb (P. sagittate) and halberd-leaved tearthumb (P. arifolia).

If you believe you have found mile-a-minute vine or would like to learn more, please contact invasives.mnap@maine.gov with the location and photos of your sighting. It’s encouraged to submit your sightings to iMapinvasives to further our understanding of where it is present. Please visit the Maine Natural Areas Program’s website under the Invasive Species tab to learn more about other invasive species in Maine, or read our mile-a-minute fact sheet.

The side of a hill which has been overgrown with mile-a-minute weed

Image: Mile-a-minute infestation forming dense mats, taking over trees and shrubs to compete for sunlight.


Climate Summary- August and September

Two graphs showing number of days' daily temperatures as compared to average.

Image: During the summer season (June-August), the number of days with daily temperatures 80°F or above were recorded in Caribou (left) and Portland (right). For both cities, days with temperatures 80°F and higher were above the average for the summer season with 39 days and 44 days above 80°F in Caribou and Portland respectively. Source: Northeast Regional Climate Center.

During this summer season (June, July, and August), weather stations in Caribou and Portland recorded higher than average days above 80°F, with 39 and 44 days respectively. Although June and July had warmer than average temperatures, the average temperature in August was closer to normal, with an average temperature around 65.5°F statewide. Southern and coastal areas experienced close to normal average temperatures for August, whereas some areas in northern Maine saw average monthly temperatures of 1–3°F warmer than historical normal temperatures. Temperatures in cities across the state are expected to have a warmer than normal start to the fall season with 2–3 weeks of above average temperatures compared to historical averages.

Two maps of Maine showing precipitation for August and September

Image: (left) Much of the state had normal or above normal precipitation totals for the month of August; (right) However, rainfall in September was sparce, with most of the state only experiencing 25–35% of normal rainfall). Source: Northeast Regional Climate Center.

Precipitation in August averaged 4.3 inches of rainfall statewide, which is slightly above average rainfall. Despite the increased precipitation we received from Hurricane Debby earlier in the month, soil moisture levels and stream flows in Washington, Lincoln, and northern Penobscot counties were low during August. Nonetheless, at the end of the month, 99.79% of the state was listed as having no drought conditions by the U.S Drought Monitor. This changed drastically in September, when precipitation levels fell to only 25–35% of normal rainfall, leading September to be one of the driest months on record. At the end of the month, only 42.7% of the state was listed as having no drought; 57.3% had abnormally dry conditions, and 8.8% of regions near the coast had moderate drought conditions going into October. Statewide averages of rainfall were estimated at 1.1 inches in September, which likely contributed to widespread drought conditions.

Two maps of Maine showing drought status

Image: (left) At the end of August, the majority of Maine had no drought conditions, except for a small region in the southernmost point classified as abnormally dry; (right) In September, most of the state was classified with abnormally dry conditions with 8.8% of the coastal regions experiencing moderate drought intensity.


This Month in Conditions Report History: October 16, 1996

“Septoria Leaf Spot of Poplar (caused by Mycosphaerella populorum syn. Septoria mussiva) – Poplar leaves statewide became spotted in July as the result of infection by the Septoria leaf spot fungus. Leaves then turned progressively brown when viewed from a distance as the season progressed, generating many calls of concern from residents and interested observers. Heavily infected leaves dropped from trees prematurely.

Septoria leaf spot was more severe than usual this year due to an unusually wet spring which provided ample infection periods. Those same weather conditions promoted heavy infection of leaves of other hardwood tree species by various other fungi, promoting a rash of calls this season regarding anthracnoses of maple, birch and ash.”


Call for Nominees to IPM Council

The Maine Integrated Pest Management Council seeks to fill a vacant seat with a qualified member of the Maine non-profit environmental organization community. Responsibilities include participating in two meetings per year (currently via video conference) and infrequent additional tasks such as reviewing, editing or distributing educational materials, policy statements, or other IPM-related outreach or education activities. Term of service is three years.

Qualifications: anyone based in Maine, actively engaged in any aspect related to being a part of a non-profit environmental organization, knowledgeable about IPM-related issues in the field, and able to represent non-profit environmental organization IPM issues and concerns across Maine is encouraged to seek appointment.

To apply: please submit a short letter of interest and a brief resume to hillary.peterson@maine.gov by November 4, 2024.

Questions? Contact Hillary Peterson (hillary.peterson@maine.gov, or 207-215-4793).


Calendar

October 15, 2024, Virtually: Forest Pest & Vegetation Management

Speakers Allison Kanoti, Gary Fish and Ronald Lemin will present information on forest insects and diseases, invasive plants and their management in Maine. Registration is required. Approved for 3 pesticide credits.

October 28, 2024, 87 Airport Rd, Old Town, ME and Virtually: Forest Tent Caterpillar in Sugarbush 

Join Maine Forest Service entomologists Brittany Schappach and Gabe LeMay, and forest health experts from other states for a forest tent caterpillar (FTC) educational session on October 28th. This free training is intended for landowners, forest managers, sugary lease holders, and educators to provide knowledge and tools for folks to make their own informed management decisions as a response to heavy defoliation damage in sugar maples from FTCs. Topics will include FTC life cycle, history in Maine, aerial survey data, impacts from defoliation on sugar maple trees, and experiences with FTC in Vermont and New Hampshire. No registration is required to attend. Watch online


Conditions Report No. 5, 2024

On-line

Department of Agriculture Conservation & Forestry, Maine Forest Service – Forest Health and Monitoring

Contributors: Aaron Bergdahl, Amy Emery, Chad Hammer (with intern Karen Karter) Gabe LeMay, Mike Parisio, Brittany Schappach, Thomas Schmeelk, Colleen Teerling, and Andy Whitman

DACF Calendar