by Roland D. Hallee

Spring has arrived in Maine, and with it, the Maine Forest Service and others have been fielding caterpillar questions. Caterpillars are essential food for many other animals, including insects, birds, mammals, and even fish! However, sometimes caterpillars from our trees and shrubs become nuisances around our homes and workplaces, and outbreak populations can threaten tree health. The caterpillars of forest tent, eastern tent and browntail moths are beginning to make their presence known.

The Maine Department of Agriculture, Conservation and Forestry urges you to take a responsible approach to living with the caterpillars in your developed landscape and avoid causing unnecessary harm to the environment and human health.

Remember that caterpillars play an important role in the environment; what you consider a pest may be someone else’s meal.
Consider no-action as a valid strategy. Sometimes, it is the most reasonable approach, but often, there are small steps you can take to reduce impacts.
If populations are unbearable or threaten a high-value ornamental tree’s health, correctly identify the caterpillar and begin with the least-toxic approach.

It is against the law to apply pesticides in ways that do not comply with label directions. Improper pesticide use can threaten human and environmental health.

The Maine Board of Pesticide Control does not recommend home-remedy pesticides. In some cases, they are illegal.

What follows are some less toxic approaches to managing tent caterpillars.

Eastern Tent Caterpillar

Tent caterpillar

This is a native caterpillar that feeds on fruit trees and shrubs (Rose family species such as cherries, apples, serviceberries, and hawthorns). It can strip ornamental and fruit trees but it is not a significant forest or human health threat in Maine. If you see them in a tree that you don’t want them to remain in throughout their caterpillar season you can:

Remove unhatched egg masses. This only will apply in cooler spots in the coldest areas of the state. We have already seen the start of eastern tent caterpillar hatch all the way to northern Aroostook County this year. Next winter, consider scouting these trees for egg masses so you can remove those prior to hatch.

Strip young colonies of caterpillars from branches within reach using gloved fingers.
Relocate developing nests to a woodland fruit tree like a black cherry or serviceberry. If you remove the twig it is on, sanitize pruning tools before use and between cuts. These caterpillars host some generalist predators and parasitoids that can help reduce other caterpillar populations.

Remove and destroy the nest. You can strip them off using your hands, or, with larger nests, put a forked twig or pole with a nail into the web, twist it, then pull the nest off. Done in the early morning or on a rainy day, you will remove most of the caterpillars that use the nest.

Forest Tent Caterpillar

Forest tent caterpillar

This is a native caterpillar that has boom and bust population cycles. Parts of Aroostook County have had several years of high populations of this insect, with caterpillars especially abundant on aspen species and also feeding on other hardwood trees and shrubs.

It is important to know that hardwood trees can tolerate a couple of years of severe defoliation before showing long-term health impacts, assuming other stresses, like drought, are not present. As a native species, this caterpillar provides important food for other species, including enemies of other insect pests.

On small, ornamental trees and shrubs, the egg masses can be removed by hand and destroyed. Note that hatch has started in northern Aroostook County and will take place over several days.

Young colonies of caterpillars can be removed from branch tips or squashed while they rest on the main stem, especially in the evening or on cool days.

In larger established landscapes experiencing their first year of defoliation, healthy trees will pull through. If this will be beyond the second year, you expect more than a third of the leaves to be consumed, you may want to consider insecticide treatment. We recommend working with a licensed pesticide applicator to treat established ornamental trees. They may use a foliar application of insecticide or a systemic treatment. If applied early enough in the life cycle, BtK, an active ingredient that has action specifically against caterpillars, can be used. It must be applied to the leaves of trees that young caterpillars are actively feeding on to be effective.

Be aware that the period of wandering caterpillars is short. Sometimes, just waiting them out is the most practical solution. If caterpillars are a nuisance around the home, they can be washed from hard surfaces like decks and siding with a strong stream of water or brushed off with a stiff-bristled broom. Where possible, follow that by removing them using a wet canister shop vac. A shop vac with a couple of inches of water in the canister can also be used to remove caterpillars from hard surfaces within reach. A couple of drops of soap added to the water will break surface tension and allow the water to suffocate the caterpillars. Be aware if you don’t clean them up, they may just climb right back where they were.

Cocoons on siding and other surfaces may be removed by a stiff-bristled broom. Test this approach in a small area first to see if the surface can withstand the treatment.

Browntail Moth

browntail moth caterpillar

This non-native species is also in an epidemic population stage in parts of Maine. Because the hairs on the caterpillar have human health impacts, if you choose to remove caterpillars, be sure to do so only after taking precautions to prevent exposure. Our website has detailed management tips for browntail moth. You can also subscribe to our browntail moth updates for more details on this insect.

Snowy tree cricket

by Roland D. Hallee

Over the last 50 years or so of my adult life, I have been involved in many activities, including coaching sports at the youth and high school levels, and have done my share of local political participation. So, in exposing myself to critics, I have been called some unflattering names. Some more colorful than others. But, one thing of which I have never been accused is being a nerd.

So, with that, I must make a confession. Although skeptical at first, I have become a follower of the now defunct TV sitcom, The Big Bang Theory. That group of nerds deals solely in science, and very rarely on practicality. My original evaluation of the show was that no one could be that nerdy. So, in one recent rerun episode, Sheldon, the “top” nerd of the group, talked about the Snowy Tree Cricket.

That was a good one. Who made up that name? It sounds contrary to anything about crickets I know. Well, I looked it up, and sure enough, it actually exists.

This is what I found. The snowy tree cricket, Oecanthus fultoni, also known as the thermometer cricket, is a species of tree cricket from North America. It feeds on leaves but also damages fruit. The chirp of this species is often dubbed onto sound tracks of films and television shows to depict a quiet summer’s night, or ridicule from an audience attending a comic’s show when they don’t think the joke was funny. The rate of chirp varies depending on the heat of the environment, allowing a listener to estimate the temperature.

The cricket’s common name of the thermometer cricket is derived from a relationship between the rate of its chirps and the temperature. An estimate of the temperature in Fahrenheit can be made by adding 40 to the number of chirps made in 15 seconds. Before 1960, the name Oecanthus niveus was wrongly applied to this species. Oecanthus fultoni was named in honor of Bentley Ball Fulton (1880 – 1960), an American entomologist who laid the principal groundwork on North American cricket classification.

Of course, if you are really interested in using the snowy tree cricket as a thermometer, you should calibrate your local crickets against a thermometer placed near where they sing. Count their chirps per minute at a variety of temperatures, graph the results, draw a line that fits the points, and use a little algebra to arrive at a handy formula.

The species is about a half inch long and is light green with translucent light green wings. It has black marks on the first and second antennal segments, that are either round or oval shaped, and is about half the length of a segment. The antennae are longer than its body and it has a small head. The eggs are pale yellow and shaped like a kidney. Its nymphs are pale and slender with wings that are not completely developed. The nymphs develop wings slowly. It has one generation per year.

American novelist Nathaniel Hawthorne said of the species’ chirps, “If moonlight could be heard, it would sound just like that.”

The species can be found throughout the United States except the southeastern part of the country. In Maine, they are predominantly in York and Cumberland counties. It is located in shrubs, vines, fruit trees, broad-leaved trees, and oaks. The cricket can rarely be found in grass. Adults of the species can be found from mid-July to mid-November. The cricket can sometimes be so high in oak trees that its chirp is the only way to identify it.

Both nymphs and adults feed on leaves and their feeding causes barely any damage. The cricket is known to destroy apples, plums, peaches, and cherries. The female drills a hole into a twig’s cambium in which to lay its egg. It then makes a row of punctures on one side of the hole and seals it with either excrement or chewed plant tissue once the egg is placed. Adults of the species eat holes in ripe fruits which results in the fruit rotting. It normally does not cause any damage in orchards that are consistently sprayed.

There is yet more to know about the song of the snowy tree cricket. Although Sheldon talked about it, the cricket never did make an appearance.

Not quite the whole show

Well, I caved in. At first showing no interest in the solar eclipse that occurred on April 8, a colleague came into the office with some extra pairs of viewing glasses. My curiosity took over.

I sat outside for approximately 25 minutes, and from my vantage point in China, I witnessed what I would classify as a 98.5 percent eclipse. In that 25 minutes, it never came to totality.

Oh well, there’s always 2044.

Roland’s trivia question of the week:

In how many Stanley Cup finals did Boston Bruins’ defenseman Bobby Orr play?

An iceberg floats past a village in Newfoundland. (photo by Terrance Klassen)

by Roland D. Hallee

A strange phenomenon occurs every spring in the north Atlantic. Large icebergs come floating down the south shore near Ferryland, Newfoundland, Canada. People journey to the site – some traveling thousands of miles – to see this spectacle.

For the locals, it’s no big deal. But for others, seeing them for the first time, it’s a breath taking sight.

Slowly, an entire flotilla of massive chunks of ice several stories high gradually make their way south from Greenland.

Most years, hundreds of icebergs break off from glaciers and their one- to three-year nomadic journey begins. If the winds are favorable enough, they reach “iceberg alley,” an area of the Atlantic that roughly stretches from the coastal waters off Labrador, in Canada, south along Newfoundland.

In 2019, 1,500 icebergs were sighted.

Meteorological and oceanographic conditions – wind direction, ocean currents and air and sea temperatures – play a role and impact the flow of the icebergs, determining how big a show Mother Nature will put on each year, according to the U.S. Coast Guard International Ice Patrol, which monitors the area off Labrador and Newfoundland for icebergs.

The icebergs have become a major attraction, giving rise to some iceberg tourism and delivering lucky spectators with a front-row seat to an unusual parade.

Tour boats actually venture out for a closer look at any number of the many icebergs. However, they never get too close in case the icebergs continue to break up.

Speaking of boats, could it be possible that one of these giant icebergs was responsible for the sinking of the RMS Titanic? The sea disaster happened on April 14, 1912, in the north Atlantic when the British luxury passenger cruise liner collided with an iceberg off the coast of Newfoundland. The timing would be right.

These gigantic icebergs in Greenland can reach up to 300-feet above sea level. That, plus most of the icebergs are not visible, with 90 percent of an iceberg’s size beneath the surface. Some take on odd shapes as they melt, even looking like ice castles by the time they pass along the Canadian shore.

As many enjoy the icebergs and all of what they have to offer, some are concerned, hoping that future generations will be able to marvel at these giants of nature as many do today.

They should be enjoyed while they last, with the current climate changes, there’s no guarantee we’ll see this spectacle in years go come.

Where to Watch

Iceberg Alley stretches from the coast of Labrador to the southeast coast of the island of Newfoundland. Some of the more popular places from shore, or from tour boats, are (from north to south): St. Lewis, Battle Harbour, Red Bay, Point Amour, St. Anthony, La Scie, Twillingate, Fogo Island, Change Islands, Bonavista, St. John’s / Cape Spear, and Bay Bulls / Witless Bay. All of these locations are accessible by road. The first four, which are on the coast of southern Labrador, can be accessed by car ferry from the island of Newfoundland year round. The further north, the longer the iceberg season.

Time of Year

The icebergs come through Iceberg Alley from spring to early summer. As you move north, the season stretches a bit longer. April and May are the months when bergs are most plentiful, but they may be locked up in sea ice, so it is suggested late May and early June for best viewing.

Are you planning a vacation to Newfoundland, yet?

So, you thought he was wrong

I’ve heard it, and even half expected it. Back on February 2, my weather prognosticating groundhog, Woodrow Charles, predicted six more weeks of winter. Everyone snickered when March came in like a lamb, and the weather just continued to improve as the month went on, to the point that by the first day of spring, there was not a snowflake to be found anywhere. My crocuses and tulips are up, my rhubarb had broken ground, even my lilac tree showed some buds. My friend the groundhog had been wrong. And then came March 23. Six weeks following February 2, a major snow occurrence, and March is going out like a lion.

Roland’s trivia question of the week:

This New England Patriots QB holds the team record for most passing yards in a season. Who is he?

Left, the spotted lanternfly. Right, tree of heaven.

by Roland D. Hallee

Just the other day, my wife showed me a Facebook post warning us about the Spotted Lanternfly, and a clear message to kill it upon sight. So, my curiousity being what it is, I had to find out, first, what it is, and second, how to eliminate it if that is what we’re supposed to do.

The Spotted Lanternfly is an invasive species native to Asia. In 2014 it was found in Pennsylvania, and has since spread to multiple counties and states which are now quarantined.

Kill it! Squash it, smash it…just get rid of it. In the fall, these bugs will lay egg masses with 30-50 eggs each. These are called bad bugs for a reason, don’t let them take over your county next.

The spotted lanternfly causes serious damage including oozing sap, wilting, leaf curling and dieback in trees, vines, crops and many other types of plants. In addition to plant damage, when spotted lanternflies feed, they excrete a sugary substance, called honeydew, that encourages the growth of black sooty mold. This mold is harmless to people however it causes damage to plants. In counties infested and quarantined for spotted lanternfly, residents report hundreds of these bad bugs that affect their quality of life and ability to enjoy the outdoors during the spring and summer months. Spotted lanternflies will cover trees, swarm in the air, and their honeydew can coat decks and play equipment.

In addition to damaging trees and affecting quality of life, the spotted lanternfly is a huge threat to agriculture industry. The economic impact could total in the hundreds of millions of dollars and hundreds of thousands of jobs for those in the grapes, apple, hops, and hardwood industries.

The spotted lanternfly adult is approximately 1 inch long and 1/2 inch wide at rest. The forewing is grey with black spots and the wings tips are reticulated black blocks outlined in grey. The hind wings have contrasting patches of red and black with a white band. The legs and head are black; the abdomen is yellow with broad black bands. Immature stages are black with white spots, and develop red patches as they grow.

While there is no active infestation of the spotted lanternfly in Maine, spotted lanternfly eggs were discovered in the Pine Tree State in 2020. Spotted lanternfly has also been seen in neighboring New Hampshire.

If you think you see any of the life stages of the spotted lanternfly, please report it to Bugwatch@maine.gov. Photos and/or specimens are required for identification and confirmation.

The Spotted Lanternfly, Lycorma delicatula, is a large planthopper native to China. It was first discovered in the United States in 2014 in southeastern Pennsylvania. SLF feeds on a wide range of host plants, including apple, grape, hops and many ornamental trees. Efforts to eradicate and quarantine spotted lanternfly have slowed its spread, but it has succesfully been able to establish in many additional states.

The Spotted Lanternfly prefers to feed on the invasive tree, Ailanthus altissima or tree-of-heaven. The geographical distribution of this tree in Maine is not fully known. Because of the strong association between spotted lanternfly and tree-of-heaven, the state is asking people to report sightings of tree-of-heaven also. Tree-of-heaven looks much like sumac.

Roland’s trivia question of the week:

Have any Boston Red Sox pitchers’ numbers been retired?

The different coats of the winter and summer ermine.

by Roland D. Hallee

Last week, I received a phone call from a reader in Palermo who told me that for only the third time in the last 17 years, he spotted an American ermine crossing his back yard.

The American ermine or American stoat, Mustela richardsonii, is a species of mustelid native to most of North America.

It was long considered conspecific with the stoat, but a 2021 study found it to be a distinct species. The finding has been accepted by the American Society of Mammalogists.

Both ermines and mink belong to the same subfamily, which contains weasels, badgers, ferrets, polecats and wolverines. These two creatures share many features, but differ in several ways.

Ermines resemble the long-tailed weasel in general both appearance and coloration, but is smaller, has a shorter tail, and has white fur on the inner side of the hind legs.

The species is found throughout most of North America aside from most of Alaska (although it is found on some islands in southeastern Alaska), eastern Yukon, most of Arctic Canada, and Greenland. It reaches the northern extent of its range in Baffin Island and a portion of eastern mainland Nunavut and ranges from here to cover almost all of western North America south to northern New Mexico, and eastern North America south to northern Virginia. It is absent from most of the Southeastern United States and the Great Plains.

The International Union for Conservation of Nature lists the ermine population as stable and of least concern.

In North America, where the ecological niche for rat- and rabbit-sized prey is taken by the larger long-tailed weasel, the American ermine preys on mice, voles, shrews, young cottontails, chipmunks, deer mice, jumping mice, and house mice. Usually the ermine kills by biting at the base of the skull. Small birds, frogs, small fish, and earthworms are other types of prey for ermines.

Ermines live and find cover from predators in hollow spaces from logs, burrows and man made structures. Ermines sometimes den within their prey’s nest and use their skin and fur as a lining for their den.

Ermines are mostly nocturnal, but may forage by day.

The ermine is listed as one of the top 100 most invasive species in the world. It was introduced to several areas to reduce rabbit populations and rapidly became a threat to ecosystems because of its vicious nature and ability to sustain itself on a variety of prey.

At one time, the ermine was sought for its attractive fur. During the winter months, the ermine’s fur turns white, making it a valuable and prized material for fur clothing. In medieval Europe, ermine fur was highly sought after for its rarity and beauty, and it was often reserved for use by royalty and other members of the nobility.

They breed in dense parts of the forest. The season for breeding is late springtime to the summer from July to August. The males mature in a year while the females only take three to four weeks to mature. The females carry a litter of four to seven babies for 255 days then gives birth.

Some of the larger wild predators of ermines are minks, martens, fishers, bobcats, coyotes, and large owls and hawks. Occasionally, a domesticated cat or dog may kill an ermine. Their small agile bodies help them evade these predators, while also allow them to compete with their predators for food in more barren months.

In spite of its bad smell and small size, however, the ermine is very self-confident, even rude – it often sits up and stares directly into the eyes of humans. Ermines do not dig its own den when they give birth, instead, they will take over old lemming burrows, food caches or graves.

According to my research, it appears that it is legal to have an ermine as a pet in Maine. However, I would advise to check with the state before owning one.

Roland’s trivia question of the week:

Which NFL team allegedly changed its geographical name in an attempt to attract a larger fan base?