Detective Dendro®: Recent Episodes
International Society of Arboriculture
Since its conception in 2004, Detective Dendro, the Diagnostic Sleuth, has been a highly popular print series with a regular feature in Arborist News magazine. In 2010, this educational and entertaining series became available as one of our ArborPod™ series.
Join Detective Dendro as he uses his professional knowledge of tree science, expert diagnostic skills, and gut instincts of a “hard-boiled detective” to investigate and identify his clients’ biotic and abiotic tree disorders. Assisted by his young apprentice, Codit, they inspect a wide range of mysterious tree afflictions, dispel the “red herrings,” and uncover the signs and symptoms that lead them to accurately diagnose trees in a variety of exotic places.
If you have comments or a favorite topic in arboriculture that you would like to learn more about, please contact us at isa@isa-arbor.com.
An assertive homeowner hopes his avocados will be the talk of the town, but the trees refuse to bear fruit. Detective Dendro is summoned to fix the problem. Will the solution be easy? (Original story by James Komen) (A,Bs)
Dendro and Codit are called to West Los Angeles by a building manager charged with tending to eight declining olive trees that are the key feature of a 41st floor outdoor restaurant. Is it Xylella fastidiosa or something else? Will Dendro and Codit have a solution in The Case of the Rooftop Restaurant? (Original story by James Komen) (A,M,Bp)
Dendro and Codit get a late Friday afternoon request. A new homeowner wants to know why his beautiful oak tree that was in pristine condition 6 months ago is now nearly dead. Dendro and Codit are on the case to figure out what caused the decline! (Original story by James Komen) (A,M,Bm)
Dendro has been busy since the storm season started. For this case, Dendro and Codit investigate why a large oak tree failed and fell across a house. It’s the Case of the Quercus Calamity! (Original story by James Komen)(A,M,Bs)
Dendro finds himself once again on the hunt. In beautiful Oceanside, California, an allée of date palms are yellowing. It’s the Case of the Deficient Palms. (Original story by James Komen and Don Hodel)(A,T,M,L,Bs)
Dendro and Codit are fresh off a week in D.C. at the annual ISA Conference and Trade Show when presented with a unique challenge; a pest targeting native as well as non-native trees, and even inanimate objects in the vicinity! It’s the Case of the Mysterious Sugar Maple. (Original story by Cláudia Coleoni)(A,M,Bs)
Dendro and Codit are called out to assess a stand of trees once featured on the silver screen and now suffering from bad pruning. Will it be an Oscar moment for the two arborists, or just rotten tomatoes in the Case of the Movie Star Trees. (Original story by James Komen)(A,M,Bm)
Dendro and Codit trade the end of winter in North America for a trip south of the equator to help diagnose a blight spreading through the region’s favored ficus’. Can they spot the cause before fica ficus becomes a Brazilian memory? It’s the Case of the Defiant Ficus (Original story by Cláudia Coleoni)(A,M,Bp)
Dendro and Codit take on a case that sounds like something from the “X-Files”; a bright orange blob of tentacles suddenly appearing on healthy trees in The Case of Justine’s Junipers (Original story by Sharon Lilly)(A,M,Bm)
Dendro and Codit respond to distressed client blaming a destroyed concrete patio on a nearby redwood. Will the tree have to come out? Is a past drainage problem really to blame, will Codit ever finish washing Dendro’s car? These answers and more in The Case of the Redwood Roots. (Original story by James Komen) (A,M,Bp)
Dendro and Codit travel across Europe and end up helping diagnose an aging giant in Sweden in the case of the Eloquent Elephant (A,M,Bm)
Dendro and Codit are across the pond at the UK’s Arboricultural Association’s annual conference when duty calls; a fungi is attacking London Plane trees, and local folks are up in arms. Can Dendro’s UK cohorts calm the masses and save the trees? It’s the case of the Plane Plan!(Original story by Sharon Lilly)(A,M,Bm)
Codit is left minding the phone on a trip to California, when a call puts him between a palm tree in a compromised planting box and an asphalt target zone. Will the intrepid side-kick figure it out? Will Dendro show up to save the day? Find out in the case of the palm’s perilous predicament.(Original story by Ellyn Shea)(A,M,Bm)
Dendro receives a letter from a veteran French arborist shedding light on a problem that has plagued his country for the better part of the last half century, and had interrupted a previous vacation for the deciduous duo. It’s the case of the Ailing Avenues, Redux. (Original story by Francis Maire)(A, M, Bm)
Our intrepid interrogator of all things trees saddles up his bike to help a damsel in distress. A recent southern Belle transplant is mourning the sudden loss of a beloved pine tree. What could have caused the sudden decline? Join Detective Dendro in the Case of the Perishing Pine. (A,M,T,L,Bs)
Dendro and Codit head to the continent for some French onion soup and bird watching, but find themselves examining sycamore trees along a French canal. The beautifully pollarded specimens are showing signs of stress far beyond the dry conditions of the past summer. It’s a historical brain teaser in the case of the ailing avenues. (A,M,Bm)
The forest Codit grew up with is under attack! Is it the neighbor’s relentlessly tapping the maples for syrup? A nearby highway poisoning the trees? Can Detective Dendro solve the mystery in The Case of the Lamentable Maples?( (A, M, Bs)
Detective Dendro steps into a home owners association dispute in an attempt to identify the source of a rouge root pushing up patios. Is the street tree destined for the mulch pile? Find out in the Case of the Plane Truth. (A,M,Bp)
Detective Dendro takes a break from watching the best tree climbers at the ITCC competition, to find himself and Codit running in circles, trying to figure out what’s causing random die-back in an otherwise healthy live oak. Will the lab have the answer? Or will this mystery remain unsolved, stumping the great Dendro himself!
On the way to the annual ISA conference and Trade Show Detective Dendro and Codit take a side trip to investigate an unknown culprit selectively targeting individual trees in a stand of pines. Will the intrepid investigators figure it out before more trees succumb? It’s the case of the peculiar pines! (A,U,T,M,L,Bs)
Dendro, Codit, and a team of international experts give an old red oak a thorough inspection with hopes of preserving the aging giant for the U.S. National Register of Big Trees. Will their findings save the historic tree a shot at immortality, or will the concerns of community neighbors mean the end for the acorn producer? Find out in The Case of the Lonely, Lashing Leader. (A,U,T,M,L,Bs)
Detective Dendro and Codit head back to the lone star state to follow up on an Elm tree slipping away while the trees around it thrive during a drought. Can the deciduous duo solve the puzzle and save the tree? Or are their efforts too little, too late?
Codit gets his big chance when Detective Dendro lets him take the lead investigating palms with withered fronds standing alongside other healthy palms of the same species. Can Codit make his mentor proud? Find out in the Case of the Frizzled Fronds.(A,U,T,M,L,Bs)
Dendro and Codit head to the east coast to help a Sugar Maple that was once saved from girdling roots but has suddenly gone into decline. What’s stressing the tree this time? Will the deciduous duo discover the cause before the local arborist pulls the plug? Can you unravel the mystery in the Case of the Confounding Clues? (A,U,T,M,L,Bs)
What’s causing established Alders to suddenly drop their leaves? Could it be somehow tied to new plantings of Maple trees? Detective Dendro and Codit tackle a baffling case north of the border in the Case of the Alder Alternative. (A,U,T,M,L,Bs)
Join Dectective Dendro and Codit as they interrupt their vacation to help a Pacific coast city arborist with a palm problem. What’s causing city palms to wilt, while private plantings thrive? Can you find the clues to solve the case of the perplexing palms?( (A,U,T,M,L,Bs)
Detective Dendro and Codit find themselves in far flung Hong Kong helping a local arborist with restoration pruning following a storm. What they discover in the trees leaves them wondering about the balance of nature, and a tree’s ability to thrive.
Detective Dendro and Codit race to save a neighborhood redwood apparently stressed by a hot summer and slated for removal. Will he solve the Case of the Curious Conifer before the chain saws start?
Detective Dendro and Codit are at it again, trying to solve the confusing case of the chlorotic Quercuses. But what about that robust redcedar? Find out on this episode of Detective Dendro©.
Detective Dendro and Codit are called in for another mystery of the decidedly salt-damaged and declining maples, but the evidence seems to indicate otherwise. Listen as the two use their canine senses to sniff out the culprit on this episode of Detective Dendro©.
Dendro and Codit are on the case again, trying to determine the feasibility of protecting a Quercus robur during construction. It doesn’t take long for Codit to need protection himself from whatever is causing the raging red rash on his festering face. Find out what Codit had a severe reaction to on this episode of Detective Dendro©.
Detective Dendro and Codit are at it again! Follow them on this adventure to British Columbia to determine why some London plane trees are afflicted with witch’s broom. Find out why on this episode of Detective Dendro®.
Detective Dendro and Codit discover three different species of oak from two different locations with one similar spiraling symptom. Can they determine what is causing the spiral bumps forming on these oak twigs? Find out on this episode of Detective Dendro®.
Detective Dendro visits a heavily manicured yard with a weeping willow (Salix babylonica), exhibiting early leaf drop and minimal new twig growth. Can he figure out what’s causing the problem before the tree wilts away? Find out on this episode of Detective Dendro®.
While hiking around Switzerland, Detective Dendro and Codit come across some Picea with broken branches and bewildering blue bark. Can Dendro and Codit determine why this forest of Picea abies is starting to deteriorate? Find out on this episode of Detective Dendro®. (Original story by Kate Leifheit and Guy Meilleur)
Can suspicious black and brown streaks on the trunk of a Quercus falcate stump the savvy crew? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Dendro takes a fall while cleaning his gutters. Can Codit fill Dendro’s shoes by completing a basic tree risk assessment on a mutilated Muehlenbergii? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Melissa marvels at the malicious masses that appear on her shagbark hickory (Carya ovata) and water oak (Quercus nigra). What is happening to her trees near the water? Find out on this episode of Detective Dendro®.
The fallacious accusations for the faulty fans of Miss Fanny LaBranche’s lilac (Syringa) bush form some indignation. Can Codit and Detective Dendro figure out the real reason for the flippant growth. Find out on this episode of Detective Dendro®. (Original story by Nora Bryan)
In the lingering last minutes before the 2013 Olympic openings, Ru Trundiep receives a shady shipment of laurels that will be used to make wreaths for the winners. Will the Olympics be placed on a hiatus? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
An old oak (Quercus) shows dieback in the upper crown and excessive pollen and acorn production. Is this mangy meek appearance calling for the tree’s end? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Is this a classic case of construction damage or is this crown dieback deceiving? Find out what is causing the city arborist, Ashley Green, to be up in arms for her ash trees (Fraxinus), on this episode of Detective Dendro®. (Original story by Wes Kocher)
A cargo mishap leads to an even more destructive dilemma: dozens of dead trees. Can Dendro relieve the distress on this dreary day? Find out on this episode of Detective Dendro®. (Original story by Don Spence)
Miss Abelha babbles about killer bees building a nest in her water oak tree (Quercus nigra). Can Detective Dendro courageously care for the Quercus without creating a crisis? (Original story by Agatha Gondim)
A tree from the 1840s with 83% hollowness still stands. Hasn’t this potentially hazardous haggard tree reached its lifespan limit? Why not remove the remains? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Can Dendro master the mystery of a multi-colored maple? Will Sal celebrate in saucy stardom for spotting a superior tree? Find out on this episode of Detective Dendro®. (Original story by Andrew Koeser)
It’s smelly, leaning, and drops fruit all over the ground. What niceties can a neighborhood find in a female Ginkgo (Ginkgo biloba)? Find out if Detective Dendro can sooth the sorrows and grievances of the town and convince them to keep this mature tree around. (Original story by Guy Meilleur)
Mrs. Fields appeals to Detective Dendro to save her Norway maple (Acer platanoides) that was attacked by a brutal bug. Can Dendro catch the crooked culprit? Find out on this episode of Detective Dendro®. (Original story by John Lloyd)
Join Detective Dendro as he puts on a different kind of detective hat to solve the disappearance of an arboreal artifact. What clues can history leave behind and what could it tell us about trees? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Dendro dives into assessing and documenting a lightning-damage claim. Did this natural force completely devastate these trees? Will a removal be needed? Will the insurance company pay the costs associated? Find out on this episode of Detective Dendro®! (Original story by Guy Meilleur)
Dendro and Codit are experiencing a row of quirks with Quercus. Oak wilt (Ceratocystis fagacearum) seems to be raiding the town, but something seems a little quaky about this particular red oak (Quercus rubra). (Original story by Justin Meier)
Even with fervent fertilization, declining honeylocusts (Gleditsia triacanthos) may put a damper on the aesthetics of a daughter’s wedding. Will Dendro be able to sooth a frightened mother’s plea? (Original story by Gavin Paul Giovagnoli)
Can a simple meat skewer help in the diagnosis of this afflicted hickory tree (Carya spp.)? Or will this tree succumb to a spurious villain? Find out what this insidious incident could indicate on this episode of Detective Dendro®. (Original story by Guy Meilleur)
A dogwood (Cornus sp.) loses over half the circumference of its bark when a truck crashes into its base. A year later, Cornelia Cornice needs an appraisal for her insurance. Does the tree need to be replaced? What are those black spots? Find out what happens on this episode of Detective Dendro. (Original story by Guy Meilleur)
A local councilman’s cherry tree (Prunus serotina) produces a heavy amount of fruit, but also shows signs of top dieback. What catastrophe caused this muddled mess? Find out on this episode of Detective Dendro®. (Original story by Alan Siewert)
Codit accepts a case with a dearth of details. Can a dog sniff out the solution of this mystery? Find out on this episode of Detective Dendro®. (Original story by Torrey Young)
Boggled by the decline of her bonsai, Lily Thordarson panics as the needles of her father’s favorite tree start to brown. Will Dendro be able to remove the dreariness of this day by treating this bleak bonsai? (Original story by Stephanie Davy)
Ruby Rubrum’s garden smells as vile as vomit. She suspects that people have been leaving the park, trespassing into her yard, and trashing her garden. Can Detective Dendro find the source of this sickening stench? Find out on this episode of Detective Dendro. (Original story by Guy Meilleur)
Could falling fronds be endangering tourists? Find out on this episode as Detective Dendro® solves a mystery about queen palms (Syagrus romanzoffiana) at a tropical resort. (Original story by Emily Parrino)
When Codit is enticed by the appeal of washboard abs, Detective Dendro gets a call to explore the mystery of a beech tree (Fagus grandifolia) with stacked-up lines of horizontal bumps on its bark. Is this a wishy-washy situation or are washboard characteristics wonderful all around? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
Jellylike horns grow on Bill Glaggett’s Juniperus. The next thing he knows his nearby crabapple (Malus sp.) have sickly yellow spots with red rings around them! How will Dendro stop this fervent fungus from fastening to something else? Find out on this episode of Detective Dendro. (Original story by Jackie Stempien)
Detective Dendro and Codit take a trip to Czech Republic enjoying fresh kolaches and steaming mugs of coffee. Amidst their exploration they find orange streaks on a group of the nation’s national tree. What caused this tremendous tearing Tilia dilemma? Can Dendro restore the trees to their rightful reputation and national claim? Find out on this episode of Detective Dendro. (Original story by Guy Meilleur and Jaroslav Kolařík)
During recess, six-year-old Woody finds a tree fungus and tries to bring it with him inside his elementary school. How will Detective Dendro get him to forgo this freaky fungus? And what does this fungus mean for the populated school’s playground? Find out on this episode of Detective Dendro. (Original story by Janet Huber)
Detective Dendro and Codit dive into the dazzling depths of the Great Barrier Reef only to spot a group of trees at a nearby site that may be in deep with pathogens. Will they be able to solve this uncharted mystery? Find out on this episode of Detective Dendro®. (Original story by Sean Freeman and Guy Meilleur)
Betty Black’s beautiful river birch (Betula nigra) is in decline. Yellowing leaves and a thinner crown has this damsel in serious distress. Betty Black calls Detective Dendro, confident he has the diagnostic skills to solve this case. But can Dendro find the causal agent of this decline? Will the birch restore its beauty once more? Find out on this episode of Detective Dendro. (Original story by Andrew Koeser)
The blue spruces (Picea pungens) and Scots pines (Pinus sylvestris) of Maple Park are showing signs of stress, so city arborist Ashley Green calls the Dendro diagnostic team in hopes of finding the root of this trouble. Could compaction be the culprit? Or does the soil tell another story? Find out in this episode of Detective Dendro®. (Original story by Janet Huber)
Black blotches on a multi-stemmed maple (Acer sp.) have Dendro’s diagnostic team bewildered. Could these black splotches be the mark of a terrible tar, or does Codit need to take a closer look under his magnifying glass? Join us to find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
On this episode of Detective Dendro, a few new helpers join the Dendro diagnosis crew. When inspecting the Carrie Ackurnel’s Carya , Dendro is assisted by her children, a group of budding detectives. Will this extra help aid Dendro in solving the case? What can they do to help keep the Ackurnels’ tree healthy? Find out on this episode of Detective Dendro®. (Original story by Guy Meilleur)
A concerned tree manager calls Dendro about his declining green ash ( Fraxinus pennsylvanica ). Upon inspection, Dendro finds a biotic agent is the culprit. Could it be the dreaded emerald ash borer? Learn about this timely issue with Detective Dendro on this week’s episode. (Original story by Michael Raupp)
In this episode of Detective Dendro, Dendro and his team must tackle The Case of the Ill Illinoinensis. Carrie Ackurnel is concerned about her precious pecan tree (Carya illinoinensis), and only Dendro can restore the hope for future tree health, and future pecan pies. In this episode Dendro will teach us about the role of pruning in tree health, and the dangerous effects of topping. (Original story by Guy Meilleur)
Join us for a new episode of Detective Dendro. When Lena Oleson’s two red oak trees (Quercus rubra) begin to display signs of wilting, Detective Dendro and Codit come to the rescue with magnifying glasses at hand. Can they crack this case, and will they discover the cause of the mysterious smell of Juicy Fruit®? Find out by listening to this episode of Detective Dendro. (Original story by Jim Zwack)
Aloha! On this episode of Detective Dendro, the whole gang will head to Hawaii to check out some tropical trees and vivacious vines. On their trip, Detective Dendro will meet a groovy island man with some challenging questions. Can this new friend stump Dendro? Find out in the Case of the Lascivious Lianas. (Original story by Guy Meilleur)
Join us for a buzz-worthy episode of Detective Dendro. Miss Suzana Abelha believes her trees may have a "killer" Africanized honey bee infestation, and only Codit and Dendro can crack the case. Will Miss Abelha avoid the sting of killer bees? Do killer bees even exist? Find out on this week's Detective Dendro, The Case of the Absolved Abelha. (Original story by Luana Vargas)
This week join us as Detective Dendro and Codit are stumbled by the staggering case of the Languishing Leylands. When Layla Compressa calls Detective Dendro concerned by the site of her Leyland cypresses, it is a sight even Detective Dendro is initially perplexed by. But with the help of Ashley Green, city arborist, and Electra Klein, utility arborist, Dendro and Codit unravel the mystery. But can they save Ms. Compressa’s Leylands? (Original story by Guy Meilleur)
Codit’s Aunt Mary-Gala McIntosh, famous for her home-made apple pies, has returned home from vacation to find her apple trees (Malus domestica) have been attacked! Can Detective Dendro crack this mysterious case for Ms. McIntosh? Will he find the time to taste her delectable pies amidst his busy day of detective work? Find out on this month’s episode of Detective Dendro, “The Case of the Flagging Fruit Trees.” (Original story by Janet Huber)
In this episode, Detective Dendro must crack “The Case of the Perishing Pines.” Holly, a dame who recently moved north from her native Nashville, believes the pine trees in her new backyard have begun to perish; will Detective Dendro solve this complex case? Have these magnificent trees suddenly begun to die? And are they even pines at all? (Original story by Sharon Lilly)
Lily Dubois, a lady who always depends on the kindness of strangers, decides to phone the famed Detective Dendro to request his investigation of her Magnolia grandiflora. In Dubois’s backyard sit two magnificent magnolias; but one of the trees is suspiciously one-sided. What caused this localized affliction, and what methods can Detective Dendro employ to help this magnolia once again provide the shade and comfort a Southern belle requires? (Original story by Guy Meilleur)
How can Detective Dendro refuse a plea for help from a Southern belle with a waxmyrtle dilemma? He and Codit come to her rescue and use their diagnostic skills to investigate dying waxmyrtle shrubs that have been sheared like a hedge to form a landscape barrier around the property. What is causing their decline, and what can be done to help them regain their health? (Original story by Guy Meilleur)
What is causing the mysterious stripping of bark from the trunks of several street trees? In Part 1 of The Case of the Sinister Stripper, Detective Dendro surveyed the site for clues and eliminated a few red herrings, despite an attractive and mystifying distraction. In Part 2, find out how Detective Dendro unravels the mystery, and then takes on a new and even more challenging assignment. (Parts 1 and 2 original story by Guy Meilleur)
Sharon Lilly, ISA’s Director of Educational Goods & Services, and Guy Meilleur, author of many Detective Dendro articles, discuss the conception and development of the Detective Dendro series for Arborist News magazine and introduce this new ArborPod series. Following, find out how Detective Dendro investigates the stripping of bark from street trees, despite an attractive distraction. Part I of this episode provides clues and sets up the introduction of a favorite character!