A Northwoods Almanac for 7/31/26 - John Bates
Spruce Budworm Killing Balsam Trees Now for Well Over a Decade
A reader in Eagle River sent me an email inquiring about balsam trees on her property that are showing signs of stress on the tips of their branches. She also noted she had seen many other balsams throughout the area that appeared to be affected.
I thought it very likely that this was due to spruce budworm, but to be sure about forest pests or tree diseases, I always email Linda Williams at the Woodruff DNR (Linda.Williams@wisconsin.gov). Linda is the “forest health specialist” there.I’ll simply quote from the information she sent me:
“Spruce budworm (Choristoneura fumiferana) is a native insect that has periodic outbreaks in the Midwest. Outbreaks occur every 30-50 years, and each outbreak lasts for an average of 10 years. Our previous outbreak ran from 1970-1980, and our current outbreak began approximately in 2012. Unfortunately, it appears populations are still going strong, and we are unsure when the population will collapse again.
“Spruce budworm preferentially feeds on current-year needles of balsam fir and spruce, [though] balsam fir is most heavily impacted . . . Tiny caterpillars overwinter on the tree and feed on expanding buds and new needles in May. The caterpillars spin silk webbing and clip needles, turning damaged foliage rusty reddish-brown, giving forests a scorched look.
“After three years of significant defoliation, or additional years of lighter defoliation, you may see dieback in the tops of trees. Repeated defoliation causes top mortality and eventually whole-tree mortality.”
Tens of thousands of balsams, as well as spruces, have been killed by spruce budworms across the Upper Midwest and in Canada, amply demonstrating that just because an insect species is native doesn’t mean it isn’t destructive.
Crucially, after the balsams and spruces have died, they become perfect torches for spreading a lightning-strike fire, which leads us to the next concern.
Fires in Canada, Smoke in the U.S.
Canada's boreal forest is one of the largest intact forests on Earth, covering about 1.3 billion acres - an area roughly the size of the entire United States. Most of this forest has no roads, no towns, and virtually no permanent human presence, meaning most of it is inaccessible - just check a map.
In July, wildfires, mostly sparked by lightning deep in these remote wilderness areas, arose and were eventually detected by satellite, often days after they began and without effective means to fight them.
The smoke billowed down into the U.S., and suddenly numerous politicians, national and local, became expert foresters, castigating Canada for poor forest management. They revived the long-standing notion that such fires were due to fuel build-up that occurred because Canadian foresters weren’t thinning enough forests and or weren’t cutting enough timber.
The facts are, of course, different. Industrial logging in Canada clear-cuts more than one million acres every year from the boreal forest. Government reports from Natural Resources Canada note that the annual industrial harvest remains relatively steady year-over-year.
To be fair regarding the mismanagement debate, in some forest systems, the suppression in particular of natural cyclical fire has indeed contributed to fuel build-ups and more catastrophic fires. But that’s specific to some dry conifer/pine systems in the western U.S.
This is Canada we’re talking about, and more importantly, this is a boreal forest where balsam fir and spruce are the dominant species.
And here’s perhaps the key point. This forest type is a fire-based ecosystem - it’s always burned and is meant to burn. The boreal burns in high-intensity crown fires on a natural cycle measured usually in a century or more, across enormous remote areas that have never been logged or thinned, or effectively suppressed. As one ecologist recently wrote, “Only about a fifth of Canada’s burned area over the past four decades was even inside forest regions that have ever been actively managed. You cannot have a fuel-buildup from forest mismanagement in a forest you were never managing.”
The mismanagement argument also leaves out the extraordinary number of standing and fallen dead trees that have been left in the wake of the spruce budworm outbreak - those trees are a crown fire in waiting. Crown fires create hurricane-like wind updrafts that carry burning bark and branches way beyond the main fire lines, thus starting spot fires across huge expanses that are often beyond the reach of limited firefighting crews. You can’t thin or prescribe-burn your way to prevent it - crown fires don’t stop at a fuel break.
Another major issue has been the weather. Record hot temperatures have been recorded in the boreal forest region along with near non-existent humidity. Fire managers are referring to the conditions in some areas as “flash droughts,” because the droughts are occurring so rapidly.
Along with all that heat have come multiple violent thunderstorms. A single lightning event on July 7–8 in northern Minnesota’s Boundary Waters Canoe Area, an area that was also sending smoke our way, sparked an estimated nineteen to twenty-one fires simultaneously across the forest. That's not the slow accumulation of small human-caused fires over a season, it's one storm system seeding dozens of fires at once, across a huge and remote area.
Now add in the fact that hot and dry weather is occurring more regularly, and lasting longer, due to climate change. Regional fire experts say this is a pattern, not an anomaly. Summer wildfires were once rare in Minnesota, but they have increased roughly tenfold since the 1990s, representing a documented shift, not a one-summer fluke.
Canadian fire seasons (May through September) have warmed about 4°F on average
since 1959 (Canada has been warming at roughly twice the global rate). That warming matters because warmer air is exponentially “thirstier”, meaning it more rapidly pulls moisture out of live vegetation and dead fuels alike, priming the landscape to burn. Fire seasons now start earlier and end later, with many more days with conditions suitable for fire spread.
Smoke doesn't carry a passport and doesn't stop at customs. No country on Earth can prevent every wildfire across a wilderness of this scale under these conditions.
Bottom line? The fires have nothing to do with mismanagement by Canadian foresters. “What is unfolding is what climate and forest scientists have been predicting for 30 years,” says Werner Kurz, a retired senior research scientist at Natural Resources Canada. “That as the world gets hotter and drier, we are exposing forests to more and more risk, and the old strategies of fire suppression are simply being overwhelmed.”
Purples and Burgundies
Late-summer wildflowers seem to specialize in shades of purple and burgundy. In bloom now are colonies of exuberant purple flowers like wild bergamot, joe-pye weed, marsh milkweed, pickerelweed, fireweed, blue vervain, steeplebush, purple asters and three invasives - spotted knapweed, purple loosestrife, and cow-vetch.
joe-pye weed, photo by John Bates
Some Good News!
Brazil’s humpback whale population has made a remarkable recovery since commercial whaling ended, rising from about 2,000 whales in 1986 to roughly 35,000 today.
Between June and November, the whales migrate from their Antarctic feeding grounds to Brazil’s warmer waters to breed. Their growing numbers have made whale-watching excursions increasingly popular and created new opportunities for responsible tourism.
National Moth Week
I suspect you didn’t know that the last full week in July is designated as National Moth Week - I didn’t! We’ll have missed it by the time this column comes out, but the moths will still be out there after the final day has passed.
Moths get short shrift next to the more popular viewing of butterflies, but many moths can mesmerize us with their coloration. Three come to mind: The brilliant lime green luna moth (Actias luna), the polyphemus moth (Antheraea polyphemus), and the daytime flying sphinx moths, which are also known as hummingbird moths because they are at first glance often mistaken for hummers (check out the white-lined sphinx moth (Hyles lineata).
Keep an eye out in the week for hummingbird moths - this is their peak time of year.
white-lined sphinx moth, photo by Bev Engstrom
Celestial Events
For planet-watching in August, look after dusk very low in the west-southwest for brilliant Venus. Saturn rises in the east after 10 p.m and then transits to the high in the southwest by dawn.
Before dawn, look in the east for Mars and Jupiter rising in the east-northeast.
August 7th marks the midway between summer solstice and autumn equinox.
Look for the Perseid meteor shower from 8/10 to 8/13 with the peak occurring on the evening of 8/12 and the predawn of 8/13. The Perseids average 60 meteors per hour, so this can be the best meteor shower of the year. Face the northeast sky, looking toward the constellation Perseus, where the meteors appear to originate. And bring a reclining chair and blanket, and allow about 20 to 30 minutes for your eyes to fully adjust to the dark. The new moon occurs this night, so if it’s a clear night, conditions will be perfect.
A partial solar eclipse will occur during the day on 8/12. In our area, the eclipse will begin at 11:45 a.m., peak at 12:18, and end at 12:51. Only a sliver of the sun will be covered.
Thought for the Week
The object of a full life “is to dig for the submerged sunrise of wonder.” - G.K. Chesterton
