Treecologic

10/30/2026

Friday Fact Corner: Right in time for Halloween, here's something scary - a leaf ID test! Leaf morphology is one of the base skills new arborists and urban foresters practice in school, but even for old pros it doesn't hurt to brush up on your less-familiar species. While the native trees of New Brunswick are estimated at 30-40 species, in the urban forest we deal with a lot of exotic species. If you count shrubs the native species list is higher, but the exotic species outstrips it greatly. For us we can't be satisfied that "a tree is a tree" since each species has unique growth characteristics that inform how we go about our jobs safely and efficiently. The way we deal with an ash (especially one killed by emerald ash borer) is different than how we deal with a black walnut, so if we can't tell them apart, we could end up putting ourselves and others in danger.

Of course most of the leaves are gone at this time of year - you might find a few on the ground but they could have blown in from further away than the base of the tree - so what can you use instead? The answer is: the rest of the tree! ID rarely comes down to one defining feature, but instead is a process of matching all the clues together to make an appearance profile. For example, a single feature is white bark: White birch has white bark, but so does European silver birch, grey birch, trembling aspen, and London planetree. So you examine other features of your white-barked tree and see that it has dark twigs thinner than a pencil (unlike trembling aspen, ruling it out), that the bark is smooth with no darker plates (unlike London planetree), and that it doesn't peel or curl at the ends (ruling out white birch - your first guess - and European silver birch). No one feature told you it was grey birch, you systematically eliminated all other possibilities to arrive at the conclusion.

Test your powers of ID on the "Trick Or Tree" specimens on the right: 2 - 5 are across the bottom, 6 - 8 are across the top (1 - Manitoba maple was damaged) and there are no repeats in the set. With 1 exception the samples are all compound leaves (1 of them is a twig with leaves attached.)

Possible ID's: Amur corktree, black locust, black walnut, Japanese pagoda tree, staghorn sumac, Tatarian honeysuckle, tree of heaven

10/23/2026

Friday Fact Corner: This surprise houseguest is a furrow spider (Larinioides cornutus), an orb-weaver spider native to North America, Europe, and eastern Asia. Their bites are about as bad as a bee sting, which is to say painful but generally not cause for undue concern unless you're allergic, and they are shy, timid spiders that don't bite unless mishandled. Furrow spiders tend to live in moist areas so you often find them on stream banks and in wetlands, but they also love gardens with sprinkler systems - this one probably wandered inside when the door to the patio was left open. Furrow spiders don't hibernate over winter, but instead allow themselves to freeze, as sugars in their body fluids stop it from crystalizing up to -20C. This means that when the temperature warms in spring, they get a head start on the season while hibernating spiders are generally still asleep for weeks yet.

Another cold-weather specialist familiar to the province is the Isabella tiger moth, or as you're more likely to know it, the woolly bear. These orange and black caterpillars outdo the furrow spider in terms of cold tolerance - they can survive winter temperatures as low as -67C! This allows them and their relatives to live in places no other caterpillar ever could, like the Arctic Circle. The arctic woolly bear has the longest lifespan of any moth, living up to 14 years, though in its defense it spends 90% of its lifespan frozen in the soil, only emerging with the summer thaw to feed for a few weeks in June and July before bedding down in the soil again. When it finally metamorphoses into a moth, it lives for only a few days in that stage, just long enough to mate and if it's a female, lay her eggs.

Overwintering as a caterpillar is one thing, but what about as a butterfly? That's what the mourning cloak does, which is why you see these large black and white butterflies fluttering around so early in the spring. In fact their colouration of dark wings bordered by white or cream helps them warm up on sunny days, concentrating the solar radiation hitting them right to their flight muscles. The undersides of their wings are greyer and resemble old fallen leaves or tree bark, which helps them blend in when they need to avoid their predators. Winter doesn't get fooled by camouflage though, so to avoid the worst of it they hide themselves in tree cavities, hollow logs, or under loose bits of bark, and live in a supercooled state until the temperature warms and they can get back on the wing.

(Apologies for the lack of post last week, I was under the weather)

10/09/2026

Friday Fact Corner: While still very small, this red velvet mite (Trombidiidae ssp.) measures a whopping 4 mm head to rear - enormous if you consider that a typical clover mite is 0.7 mm long, and a spider mite is 0.2 mm long or smaller. Unlike clover and spider mites, red velvet mites are predators and pose no danger to your grass or gardens. There are over 300 species of red velvet mites native to North America but their exact taxonomy and distribution aren't well understood at present. These critters spend most of their early life as parasites of other insects and spiders, and later become predators in the soil and leaf litter, hunting down tiny prey like other mites, springtails, and beetle larvae. In the fall the adults emerge on cool, rainy days to search out mates and lay eggs - they are sometimes called "rain bugs" for this reason.

Another red bug you might see at this time of year in numbers are lady beetles. Unlike many native terrestrial arthropods, lady beetles live as adults for several years, looking for warm, sheltered places to spend the winter. These hibernacula can be abandoned rodent burrows, hollow logs or tree cavities, or man-made structures like sheds, attics, and parked vehicles. The issues is lady beetles don't like to overwinter alone, so they send out aggregation pheromones to invite 100-200 of their closest friends to have an all-winter slumber party. This isn't an issue if they find a nice natural cave to bunk down in, but when they decide to occupy an otherwise occupied house it can be hard to remember that they're beneficial insects, not pests.

Another native insect that likes to invite itself indoors for the winter is the boxelder bug. These red and black insects feed on Manitoba maples are aren't much of a plant health issue in the summer, in spite of their large numbers. They become a nuisance when they seek out hibernacula for overwintering and decide that your siding, windowsills, or house interior is the place for them. To keep them from coming in, check the seals around windows and doors and repair them if necessary - the same goes for window and door screens. Bathroom and kitchen vent screens should also be checked for the same reason. For large gaps, especially in attics and crawlspaces, make a temporary patch with spray foam until you can reinforce the area properly. And if any do get in, sweep them up and toss them outside - they aren't dangerous to humans, just annoying!

10/02/2026

Friday Fact Corner: On September 15, 2026, the Canadian Food Inspection Agency (CFIA) confirmed the first detection of invasive Spotted Lanternfly (SLF) in Canada in Windsor, Ontario. Since this official announcement a number of new sightings and interceptions of SLF have been reported, mostly along the Windsor/Detroit border. Movement restrictions have been put in place at the CFIA detection site to prevent the movement of regulated materials, including potentially infested plant materials and firewood. Surveillance in the surrounding area is on-going to determine the extent of the infestation and next steps.

Currently, Ontario horticulture and grape growers face the highest risk, but green professionals across Canada need to be vigilant, as SLF spreads on conveyances too. SLF originally came to North America on a shipment of landscaping stones, and has spread throughout the eastern United States through both movement of nursery stock and by hitchhiking on vehicles. The few interceptions in the Maritimes have been on ferries, where the insect likely hopped onto a car and rode long-distance before being found and squashed. While their favoured host Tree-of-Heaven is unlikely to establish itself widely in New Brunswick, SLF is known to feed on over 100 species of broadleaved tree and shrub.

Once CFIA completes their surveillance of the detection area, they will set up regulated areas for SLF. If you are travelling through a regulated area in Canada or the US, take extra care inspecting your vehicles before you leave and after you stop at any point in your trip. Going through a carwash is a good idea to make sure any adults looking to mooch a ride meet a soapy end instead, and if you're picking up a vehicle or equipment that was sitting in the open for a while, check it carefully for the grey putty-like egg masses before loading it. If you're climbing in or near an outbreak location, carefully check all of your gear for stowaways and give everything a thorough cleaning before you put it away. Below are some resources to familiarize yourself with SLF. Put the "spot" in "spotted lanternfly", and report any findings to CFIA!

https://buff.ly/b8MTDgt CFIA reporting page
https://buff.ly/RY3qs6R USDA SLF information page
https://buff.ly/w4CraXd Invasive Species Center SLF information hub

In an effort to prevent its introduction and spread into Canada, spotted lanternfly (Lycorma delicatula, Hemiptera: Fulgoridae) has been regulated by the CFIA since 2018. It can feed on more than 100 species of trees and plants. It is not known to be present in Canada, but poses a significant threat...

09/25/2026

Friday Fact Corner: Fall is here and while some of us aren't ready to see summer go, the blow is softened by getting to see the red maples (Acer rubrum) decked out in their seasonal finery. Red maples are native to much of eastern North America and make up a large portion of the maple trees in New Brunswick. Red maples are hardy and adaptable trees, growing at the edges of swamps, along rivers, in mixed forest stands, at roadsides, and in towns and cities. Their smaller stature at maturity (for a tree, mind you, so it can still be in excess of 60 ft), beautiful fall colours, and rapid establishment on site make them very popular urban trees. Pick any neighbourhood in Fredericton and you're all but guaranteed to find at least one in a front or back yard.

Red maples aren't just red for fall though, they also show their colours in spring. Red maples are among the earliest trees to bloom, plumping up their clustered round buds at the ends of twigs around mid-March and coming into bloom in April. The flowers have red pistils and petals, the bud scales are red, and the new twigs also flush red as they warm up for the year. Some tree guides also point to the red petiole (leaf stem) as a source of the name, but this isn't a guaranteed species characteristic, and is also shared by other maples occasionally. Many of these features are shared by Freeman maples, which is a natural hybrid of red and silver maples, though in general it can be told apart from red maple by its larger leaves with deeper sinuses between the lobes, and greater number of lobes (Freeman typically has 5 while red usually has 3).

Red maples are sometimes called "soft maples" along with silver and Freeman maples, in comparison to "hard maples" like sugar and black maples, and that's down to their wood characteristics. Unlike a true hardwood like sugar maple, red maple wood is light and soft, not unlike pine or poplar, though it is quite strong. Red maple wood is rarely sawn for lumber even where it grows abundantly, and is mainly used to make specialty products, musical instruments, kitchenware, pallets, crates, and boxes. It is sometimes used for pulp, and if it has a curly or quilted grain it may be processed for veneer. Though it offers less BTU output than red oak or sugar maple, it is desirable as firewood because it seasons quickly and burns readily, not needing much coaxing to ignite, and it splits fairly easily.

09/18/2026

Friday Fact Corner: This ginkgo (Ginkgo biloba) hasn't been caged in for your safety (probably), but is inside of the tree protection zone. A tree protection zone (TPZ) is a clearly-marked and fenced-off area around a tree or group of trees in or adjacent to a construction site or other area where long-term hazards to tree health, like heavy equipment and site alteration, are taking place for a prolonged period. These are environments where a site plan and some flagging tape aren't enough, and where the trees are highly valued. Municipalities with single-tree protection bylaws often have clauses about establishment of TPZ's to protect trees when construction needs to happen, as a way of protecting the town's green assets.

While they don't have an internal anatomy like humans, if a tree can be said to have a "heart" or a "brain" it would probably be its roots. Tree roots do a lot more than just drink water: they take in nutrients, help regulate its respiration, store starch to survive the winter, make connections with mycorrhizal fungi, engage in allelopathic warfare with competing plants, and form networks with their offspring. A tree with compromised roots can quickly succumb from water and nutrient deficiency, or more slowly from soil pathogens. Tree roots are also highly structural and help anchor them in place - a tree can't duck down out of the wind when it starts blowing. A tree that loses a large volume of roots is susceptible with windthrow, and with shallow-rooted species like poplars and willows, the risk that much greater.

You may notice that the TPZ around this tree is wider than the canopy, and that's by design. Ideally a TPZ should protect as much of the tree's critical root zone as possible. The structure of a tree below ground may look like a lollipop in its simplest expression, but when you include the roots, a better visual analogy is more like a w**e glass on a dinnerplate. The root network of most trees is at least half again as wide as the canopy. The greater proportion of the root zone that can be remain unharmed during site alteration, the better -off this tree will be and the greater the likelihood that it can recover from the damage. For smaller and newly-planted trees on the other hand, the TPZ may not extend much beyond the drip line since the root volume is much smaller.

09/11/2026

A large piece of artist conk (Ganoderma applanatum) makes a handy canvas if you have an artistic flair. This wood-decay fungus attacks mature hardwoods and causes heartrot, often in beeches and poplars. While their presence means that the tree in question is rotten and should be removed if it poses a hazard, the bracket fungus itself can be harvested and given new life as a decorative object. The pale spores sitting above the brown cortex of the fungus are very sensitive to disturbance and brush off with the slightest touch - take care when harvesting it to only touch the top and the sides. Artist conk is best worked straight away before it dries out, though with harder tools like a stylus or the end of a knitting needle, you can draw on it up to a week later. Once fully dried the marks are set and aren't easily scuffed or smudged.

Another great find on a tree being pruned or removed is chaga fungus. This charcoal-like growth is the sterile portion of the fungus which colonizes birches, especially old-growth white and grey birch. When dried and prepared properly it can be used to make a tea that reportedly improves immune function and lowers blood pressure. When harvesting from a live tree it's important only to take a small portion of the growths to avoid damaging the tree and allowing the fungus to proliferate naturally in the stand. For trees being removed and especially for trees being chipped, you may as well take the lot. Bear in mind its amorphous, charcoal-like shape though so you don't confuse it with another black fungus growing on decaying birch: tinder polypore. This is a more classic shelf fungus in shape and while you can't make tea from it, it is useful for tending fires in the wilderness since it lights easily and burns slowly.

Perhaps the most exciting find from a felled tree is a burl. Caused by insects, fungi, bacterial and viral diseases, or abiotic growth irregularities, a burl is basically a benign growth in the wood, often on the trunk or a large branch. The grain of the wood in a burl is much tighter and more complex than the normal woodgrain, and may feature unusual structures like bird's-eye dots, whorls and loops, spalting (especially if the burl was caused by fungi), and chatoyancy (a rare shimmering effect from translucence along one aspect of the grain.) Burls are interesting as-is, especially when the bark is removed to show the highly-textured wood beneath, but due to the density and their tendency to be round, many burls are turned into bowls. While wood-turning is a time-honed skill, it's also a great way to pass the time over winter. Collecting and drying burls now means you'll have a ready supply to practice with later - or a quick infusion of cash if you'd prefer to find an interested burl buyer instead!

09/04/2026

Friday Fact Corner: This hungry milkweed tussock moth (Euchaetes egle) doesn't want to be bothered while it's eating, and it lets predators know that with its dramatic colouration of orange, white, and black. High-contrast colour combinations like these are common in the animal world and are called aposematic warning colours. They're used by venomous (wasps and bees), poisonous (juvenile eastern newts), bad-tasting (lady beetles), or bad-smelling (skunks) animals, helping them avoid trouble if trouble comes looking for them. In the case of milkweed tussock moths, they have two warnings going for them: they are brightly coloured (indicating they taste bad) and they're covered in dense prickly hairs (makes them look bigger and less appetizing). Unlike many tussock moths the hairs are not dangerous, but you can still experience a mild rash if you handle them - better to do what their warning colours suggest and leave them alone to eat their milkweed in peace.

Some caterpillars in the province are actually dangerous to humans though, and should be given a wide berth if encountered. A cousin of the milkweed tussock moth is hickory tussock moth, and these black and white caterpillars are best avoided. These caterpillars are furry and white with a black line down their back and 4 long "spikes" of venomous hairs, and are often found feeding in walnuts, oaks, and hickories. Touching their hairs can cause a serious allergic reaction on par with poison ivy, and they often feed in numbers - if you find 1 in a tree there's likely 20 or 30 more somewhere nearby. A smiliar-looking caterpillar that is yellow instead of white and lacks the black stripe is the American dagger moth, and it also has 4 long venomous guard hairs that can give you a nasty rash. Fortunately these caterpillars are solitary, and thus easier to avoid accidentally encountering.

Probably the most common "Warning colours"-wearing insect we encounter are yellowjackets. At this time of year they are done rearing larvae and the queens have abandoned their nests, looking for places to overwinter. Once the boss leaves the building, the worker wasps are free to make nuisances of themselves looking for sugar - normally they get this from the larvae, that secrete a sweet substance to feed their sisters after getting a protein meal. Since they can't get that home-cooked meal anymore, they cruise the neighbourhood looking for unattended drinks, fallen fruit, and anything that smells vaguely sweet or flowery. Keep a can or two of wasp-killer on vehicles, check your climbing route thoroughly before ascending, and make sure to keep drink and food containers sealed when not in use - the last thing you want to do is accidentally have a wasp in your mouth!

08/28/2026

Friday Fact Corner: This little-leaf linden (Tilia cordata) is called such because its leaves are quite small compared to other lindens, especially American basswood (which itself is known for its extremely large leaves). You could be forgiven for thinking the name is in reference to how little leaves this tree has left at the end of summer, and it isn't the only one. Bare Norway maples and sun-scorched horse-chestnuts bear testament to how hot a summer we had, especially those in really adverse planting sites like this boulevard. A combination of drought, restricted root zone, the urban heat island, and radiant heat from hard surfaces means this tree never gets a break, so it can be forgiven for seeming to be packing it in early - it's just doing what it needs to in order to survive.

Early fall colour and leaf drop is directly a stress response to extreme heat and drought, and is the plant’s way of protecting itself from additional water loss. Diseases like tar spot, anthracnose, and vascular diseases like dutch elm disease make the stress worse and leaf drop more pronounced. When broadleaf plants are under severe stress they prioritize their long-term health over their seasonal gains and enter dormancy early. Leaves turn colours in a patchy/spotty way, often on the sunward side of the plant first, and gradually fall off, as opposed to cleanly transitioning to fall colours and then shedding rapidly like they normally do. Sudden leaf drop with mostly green leaves and crispy edges is a more serious sign of stress yet - the plant can’t afford to wait to shut down its leaves properly and jettisons them to avoid critical moisture loss. A plant under stress from damaged or waterlogged roots can’t take the added stress of high soil temperature and hot, dry days, and puts itself dormant in order to wait out the poor conditions.

After three seasons of stress, leaf spots are also showing up on many species of broadleaf trees and shrubs. Whether maple tar spot on your Crimson King, septoria on your bigleaf hydrangea, spot anthracnose on your dogwood, or black spot on roses, there’s a spot for every occasion. The good news is these are mostly aesthetic diseases that don’t threaten the health of the affected plants overly, the bad news is there isn’t much to be done about them once they appear. Prevention is key to leaf spot diseases, and no amount of prevention goes further than lowering the plant’s stress. Make sure new plants are fertilized on time, that they receive adequate water especially in hot and dry weather, and that their soil drainage is correct for their species. The right plant on the right site stands a much higher chance against adverse conditions than one that struggles right out of the gate.

08/21/2026

Friday Fact Corner: This jaunty male American goldfinch (Spinus tristis) is a familiar sight in the urban forest and rural landscapes across New Brunswick. Goldfinches can be found right across the continent, from Nova Scotia to coastal British Columbia, though their range northward is more limited. The northern population migrates to Florida and Mexico, while those in southerly locations are residential, though they may move through the landscape in modest flocks to chase emerging food sources. They are some of the last birds to migrate south though, and some urban birds are year-round residents, eating winter berries and wildflowers seeds, as well as taking advantage of backyard birdfeeders.

In their breeding plumage, male goldfinches are very distinct with their black cap and wings, and highlighter-yellow body. The females are more of an olive-green with yellow highlights, and these are brighter in the breeding season as well. Non-breeding males still retain some yellow but resemble females with black caps. Their song gives them away at any time of year, sounding like a high-pitched voice asking "Hey-huy?" and then chuckling at the reply. In flight they have a characteristic "rolling" wingbeat, where they flap quickly, coast, and flap quickly again, like a sine wave in the air. They tend to stick to their own in the breeding season but will join mixed-species flocks in fall alongside house finches, juncos, and chickadees.

Unlike many native birds, goldfinches have largely benefitted from human alteration to their environment. They prefer edge habitats with a mix of forest and field, especially if it contains low to medium-height shrubs where they can nest. Cutovers left to naturally regenerate are often utilized by goldfinches, especially if they contain tall grass and wildflowers. A yard with shrubs and perennials is also perfect for them, as they forage for insects in spring and feed on seeds and berries over summer and into fall. Goldfinches especially love thistle and coneflower seeds, and many specialty finch feeders suggest filling them with niger seeds, which are of a similar size. Watching a goldfinch adroitly flit in place while harvesting seeds gives you a real appreciation for these charming little birds we share the urban forest with!