New York State IPM Program

September 20, 2018
by Debra E. Marvin
Comments Off on Boxwood Blight is Breaking the Bank

Boxwood Blight is Breaking the Bank

Boxwood blight, Cylindrocladium buxicola, was first identified in 2011 when submitted samples were examined at the Connecticut Agricultural Experiment Station. This marked the first confirmed cases outside of the UK and New Zealand. Since then, it’s been found on many cultivars of boxwood, Buxus spp., up and down the east coast.

Boxwood Blight, Photo credit Oregon Department of Agriculture

Now, it’s not only showing up in many downstate counties and Long Island, but completely decimating formal gardens and landscape nurseries. With various landscape and cutting uses, Boxwood is a million dollar plus industry, including its use as a major component in holiday wreaths and decorations.

Boxwood Blight, photo credit Margery Daughtery

While boxwood blight might not be a concern in your yard, you’d notice its loss in many landscapes. This is a major concern of landscapers, horticulturalists and growers.

Boxwood blight shows up as dark brown spots on leaves. These lesions enlarge with dark borders until they merge with others. By then an entire leaf—and many nearby—may be covered. These browned out or straw-colored dead leaves drop in record time. “That’s why they call it a blight.”

Stem infection also occurs and shows up as long black lesions. This FUNGAL DISEASE forms sporadochia (fruiting structures), visible with a hand lens. In layman’s terms, sporadochia produce sticky spores—nasty seeds of destruction if you’re a fungal disease! Spores happily spread by wind, rain, splashing water, or by hitchhiking on you, your lawnmower and rake, your dog, even your favorite garden birds.

Why this sudden outbreak? Anyone who suffered through this swampy summer can guess. According to Cornell Alum and New York State Climatologist, Mark Wysocki, “This is more typical for the Gulf Coast states.” Syracuse, for example, sweated through 531 hours when the dew point, a standard measure of humidity, was at least 70 degrees. That’s more than double the number of sticky hours of the next closest year, 2005.

THIS CHART SHOWS # OF HOURS OF DEWPOINT >= 70 at Ithaca Tompkins Airport by year 1996-2018

With relatively new pests, IPM and conventional treatment options aren’t time-tested. Other factors such as soil health, over or under-watering and winter injury increase susceptibility, but this year’s humidity has come at a high cost to boxwood.

For more on boxwood blight, here are two great resources:

Connecticut Agricultural Experiment Station, Dr. Sharon M. Douglas

 Margery Daughtery, Long Island Horticultural Research and Extension Center for Cornell University.

May 24, 2018
by Joellen Lampman
Comments Off on Minimize tick risk while minimizing pesticide risk

Minimize tick risk while minimizing pesticide risk

“I already found a tick on me!” – many people across NY

Many New Yorkers still equate tick activity with summertime, but blacklegged ticks, the ones that carry Lyme disease, anaplasmosis, babesiosis, Powassan virus, and Borrelia miamyoti, are most active in the spring and fall. (They can actually be active year round if the temperature and humidity levels are just right. Thus the heavy activity on the warm days in February.)

The goal is to prevent ticks from becoming embedded in the first place. But if you do find an embedded tick, remove it properly!

And in the springtime the blacklegged tick nymph turns to thoughts of questing. And nymphs are small. Poppy seed-sized small. If you are not intentionally conducting a daily tick check, you could easily miss one. And even if you are intentionally looking, one can occasionally get through your visual defenses. Which is why I was able to take this tick removal video after finding this tiny nymph on my leg when using my fingertips to search by feel. Since Powassan virus can be transmitted after 15 minutes of the tick being embedded, the incentive for not being bitten has risen dramatically.

Which brings us to the use of clothing treatments to protect ourselves. Permethrin is a pesticide that can be applied to clothing, footwear and gear before exposure. Researchers for the Center for Disease Control recently conducted a study showing how permethrin interferes with blacklegged, American dog, and lone star ticks’ ability to move and, thus, to bite. Read about it here.

Now the easiest option is to buy pretreated clothing or have your clothes professionally treated. The TickEncounter Resource Center has an excellent section of their website about tick repellent clothes, including where to get them.

For DIYers, permethrin can be purchased at many sporting goods and big box stores as a liquid or aerosol spray. But it must be applied safely and correctly. I try not to react in horror as people tell me they will spray the clothes they are wearing just prior to walking out the door. This product must NOT be applied to clothing while it is being worn. Or when one’s husband announces that he left his newly treated clothing in the basement. (And, yes, he sprayed the clothes down there too.) Permethrin must be applied outdoors. Don’t take my word for it. This information, and more, is found on the label. Let’s take a close look at the label from a commonly found product. (Does not imply endorsement.)

The label is the law and will tell you everything you need to know about using a pesticide correctly and legally.

The label, which is vetted through the EPA and, in NY, the DEC, provides information on the following topics (with a few examples thrown in):

  • Signal Word – this is your clue to how dangerous the pesticide is. To put it simply, categories include Caution (slightly toxic), Warning (moderately toxic), and Danger (highly toxic). This formulation of permethrin is labeled Caution.
  • DIRECTIONS FOR USE – includes, but is not limited to:
    • SHAKE WELL BEFORE USING. (Emphasis theirs. It must be important!)
    • This product must not be applied to clothing while it is being worn. Under no circumstances should bare skin or clothing on the body be treated. (Emphasis also theirs.)
    • Make all applications outside.
  • STORAGE & DISPOSAL
    • Store in a cool, dry place inaccessible to children.
    • Never place unused product down any indoor or outdoor drain
  • PRECAUTIONARY STATEMENTS – includes “Do not use on humans.”
  • FIRST AID – in case you didn’t follow the precautionary statements.
  • ENVIRONMENTAL HAZARDS
    • This product is extremely toxic to fish and other aquatic organisms.

We hit just some of the highlights, but it is all important. The label not only provides suggestions for using the product safely – the label is the law. That too is on the label: “Buyer assumes all risks of use, storage or handling of this product not in strict accordance with directions given herewith.”

So what is one to do? Why, follow the label of course. Decide which clothes you might wear into tick infested places and “select an outdoor area protected from the wind, spray outer surfaces of clothing (while not being worn) with a slow sweeping motion to lightly moisten the surface of the fabric, holding pump at a distance of 6 to 8 inches. Treat outer surfaces of each outfit, front and back, for 30 seconds on each side and allow to dry for at least 2 hours (4 hours under humid conditions). Pay particular attention to socks, trouser cuffs, and shirt cuffs.”

Then plan for the next application. “Clothing should be retreated after six weeks or after the sixth laundering to maintain adequate protection” I both mark the day I sprayed in my calendar and schedule an appointment for six weeks later.

By the way, professionally treated clothing also has a label, often found on the hang tag when purchased. Be sure to follow those instructions carefully as well.

For more information about permethrin, visit the National Pesticide Information Center and EPA. And for more information on ticks, tick-borne diseases, why there are so many of them, and how to protect yourself, check out our new improved tick page – www.dontgettickedny.org.

April 27, 2018
by Mary M. Woodsen
Comments Off on The New Tick in Town (Part ll.)

The New Tick in Town (Part ll.)

Now for the science-y part of this post. (I suggest you re-read Part l. Can’t hurt. Might help.)

If you’ve read our other posts on the blacklegged tick (aka the deer tick), you might guess—and rightly so—that it’s the tick that’s been on our radar the longest; the one we (still) give most of our time and attention to. And all for good reason.

Sheer numbers (how much Lyme disease we’ve seen; what the co-infections are and how commonplace they are; its reputation as the “great imitator”) keep the blacklegged tick in the spotlight. Meanwhile, with the exception of Long Island, the lone star tick is rarely seen in the metro New York area and points north. But it has colonized some islands off Connecticut and established a toehold on Cape Cod in Massachusetts.

The lone star tick is on a roll, with its own suite of diseases and syndromes, some still mysterious. (Credit CDC)

Indeed, the lone star tick’s potential for harm could, somewhere down the pike, become a force all northerners face.

And consider this: though deer serve as a great food source and taxi service for ticks, they are immune to Lyme disease. Not so with the lone star tick. Because given the right circumstances, it can kill even deer.

So … what diseases or conditions does this tick carry—and could any be fatal to people? Here’s the short list:

  • Ehrlichiosis is nasty. Upward of two percent of those who get it might die.
  • Tularemia is nasty too, though less so than ehrlichiosis.
  • Heartland virus is rare—and most people who do get it have mild symptoms; perhaps none at all. But yes, some will die.
  • Alpha-gal syndrome? Perhaps—especially if you don’t know it for what it is. While the symptoms can be frighteningly intense, not everyone reacts with that same level of intensity. Plus this syndrome’s transcontinental spread in places lacking lone star ticks leads to yet-unanswered questions.

Ouch! Lone star ticks attach quickly—and some people react quickly. Sometimes it looks like this. (Credit: Copyright © 2015 American Medical Association)

So how about STARI, or southern tick-associated rash illness—can it do you in? My careful search turned up zilch, zip, zero. Doesn’t mean STARI won’t send you to an early grave. But if it could, I can’t find credentialed scientific sources to back up such a claim. You’ll be interested to know, though, that the rash STARI stands for can, on the surface of things, make you think you might have Lyme disease. And more unanswered questions: as of August 2017, the pathogen that causes STARI remains unknown.

 

 

 

Sources:

 

 

 

November 16, 2017
by Joellen Lampman
Comments Off on Sandbox or Litterbox – You Decide

Sandbox or Litterbox – You Decide

Raccoons are pretty cute, but you really don’t want them pooping on the property. Photo: Nell McIntosh

We don’t have to go to wild places to find wildlife. A surprisingly wide range of species can be found in our sities and towns, from familiar animals like the raccoon to more exotic ones like the mountain lion. – Roger Tory Peterson

When I was younger, raccoons were my favorite animal. It was hard to resist their clever little hands and cute bandit masks. My stuffed raccoon was named Rickie. Even when I was old enough to learn about rabies, my love didn’t wane. But then, when taking a wildlife rehabilitation workshop, I learned about Baylisascaris procyonis (raccoon roundworm), an intestinal parasite passed in raccoon poo.

The speakers at that workshop recommended using a blowtorch to kill the eggs of this intestinal parasite which, terrifyingly, can enter our eyes and nervous systems. The cuddly raccoon lost its place in my heart.

My love-hate relationship with raccoons came to mind when I saw the CDC has released a fact sheet on raccoon latrines and Baylisascaris procyonis. I do work quite a bit with school and child care facilities with their obligatory playgrounds. The CDC notes that “young children or developmentally disabled persons are at highest risk for infection, as they may be more likely to put contaminated fingers, soil, or objects into their mouths.” But they fail to point out that sandboxes can serve as a raccoon latrine. (It’s listed as a possibility here.) Of course, cats, which carry their own suite of parasites, are more likely to use sandboxes as their own personal litter box. It’s good IPM to prevent all types of animals from accessing your sandboxes.

The idea is good, but the implementation is lacking. Without securing the tarp, animals can easily slip under it. Photo: Joellen Lampman

No need to rid your property of sandboxes — indeed, there are sensory and group play opportunities with sandboxes (just Google “sand play activities”). But you must prevent animals from gaining access. Here’s how:

  • Keep sanitation a priority to avoid attracting wildlife – ensure that trash is cleaned up and put in a sealed container at the end of each day. (This will also help with other pests such as rats and yellow jackets.)
  • Have a “no food in the sandbox” rule – there is no need to provide an enticement for local animals to check out the box.
  • Have a solid box bottom — not only will this help prevent sand loss, but it keeps critters from burrowing in from underneath.
  • Have a durable cover on your box and make sure it is only uncovered during playtime.
  • Pest proof your buildings (including outbuildings) to reduce den sites. Raccoons will gladly set up facilities in your attic or garden shed.

    Sandbox with cover rolled back. Photo: Gil Garcia

    Tarp ties on the sandbox hold the tarp securely in place. Photo: Gil Garcia

If you find a latrine, check out the CDC fact sheet that includes information on cleaning it up while protecting your health. (Spoiler alert: they also recommend using a propane torch, since chemicals will not kill the eggs.)

Just a note that raccoon latrines can be found in other areas, including (yikes!) inside buildings. Be sure to pest proof your buildings to prevent raccoons (and squirrels and bats and birds) from making your building their new den. To keep wildlife out of your buildings and discourage them from your grounds, visit the NYS IPM Program web page: What’s Bugging You: Wayward Wanderers.

November 7, 2017
by Mary M. Woodsen
Comments Off on Pollinators, awards — and IPM

Pollinators, awards — and IPM

Just one short week ago, we celebrated the College of Agriculture and Life Science at Cornell University’s Outstanding Accomplishments in Extension and Outreach Award. This award honors a team effort that benefits an important segment of the population or area of the state.

It takes teamwork — whether you’re a bee or a researcher. (Photo Sasha Israel)

New York, like the rest of the world, is highly dependent on the hundreds of species of crop pollinators that collectively contribute roughly $170 billion a year to the global economy. Many are in decline and under threat in New York and elsewhere.

That’s why Dean Kathryn J. Boor ’80 recognized the Cornell Pollinator Health Team for their outstanding outreach accomplishments in a ceremony that celebrated research, extension and staff excellence.

Pollinator Team at the 2017 CALS Award Ceremony

On hand to accept from Dean Kathryn Boor (L) were (L-R) Jennifer Grant, Bryan Danforth, Dan Wixted and Scott McArt.

The seven-member team includes entomologists, extension  outreach specialists and pest management experts  — one being NYS IPM‘s director Jennifer Grant.

The team provides critical extension and outreach on pollinator declines, including information on

  • optimal habitats for honey bees, native bees, and other pollinators
  • diseases that afflict bees
  • how pesticides affect bees — other pollinators too
  • what to do when your honey bees are in decline

Hi. I’m a hover fly and I pollinate lots of plants too. Plus my larvae eat aphids for breakfast, lunch and dinner. And no, I won’t sting you. (Photo credit Susan Ellis.)

With its focus on extension and outreach, the team has given more than 70 extension talks over the past three years in New York and elsewhere on pollinator health, bee diversity, integrated pest management practices and pesticide recommendations that minimize risks to bees — to all pollinators, in fact. Their audiences have included beekeepers, farmers, and lawmakers — as well as state and national organizations such as the New York Farm Bureau, the Audubon Society and Future Farmers of America.

“In three short years, the work of this team has made a notable impact both in scope and relevance to beekeepers,” Boor said at the ceremony. “The pollinator health team represents a model for how collaboration among different units at Cornell can lead to highly integrative and creative extension and outreach.”

July 20, 2017
by Abby Seaman
Comments Off on Got late blight in your garden? Here’s what to do.

Got late blight in your garden? Here’s what to do.

An upside of last year’s dry growing season is that we had no reports in New York of late blight, the devastating disease of tomato and potato.

But 2017 is shaping up to be a very different season. We had our first late blight report in Erie County July 10th — and another one from Livingston County on the 13th.

Late blight has a toehold on your tomatoes. Act now.

Anyone growing tomatoes or potatoes should be aware of the risk and be alert for the first signs of late blight infection. Learn how to identify late blight — good IPM! — and distinguish it from other diseases with the Distinguishing Late Blight from Other Tomato and Potato Diseases and Identifying and Scouting for Late Blight on Farms videos.

You could also take a sample to your local Cornell Cooperative Extension office for diagnosis. Find your local Extension office at the Cornell Cooperative Extension web site.

Preventing Late Blight

The pathogen that causes late blight in the U.S. overwinters only in living potato tubers. To prevent late blight

  • be sure no infected tubers get through the winter alive
  • immediately destroy any plants that come up from potatoes that didn’t get harvested last year
  • plant certified seed potatoes.

Yet even if you do everything to prevent late blight from getting started in your garden, spores from nearby infected plants can be carried through the air to land on your tomatoes or potatoes.

Plant tomato varieties resistant to late blight to help prevent it from killing your plants — and prevention is a key tenet of IPM. Find a list of late blight resistant varieties in the article Late Blight Management in Tomato with Resistant Varieties.

Some varieties of potato — Elba, Kennebec, Sebago, and Serran among them — have some resistance; they will slow but not prevent late blight infection. If late blight becomes prevalent in your area, fungicides can protect your plants.

But act quickly, applying fungicide before plants are infected. Why? Products available for gardens cannot cure existing infections.

Want to track where late blight has been found? Sign up for text or email alerts on the usablight.org web site.

What to do if you find late blight in your garden

Take immediate action — otherwise you’ll be a source of infection for other gardens and farms. Infected plants release hundreds of thousands of spores that move on the breeze. But first confirm that what you have is late blight and not another tomato or potato disease.

County Cornell Cooperative Extension offices can offer a diagnosis or can submit a sample through the usablight.org web site. Reporting your find on usablight.org and submitting close-up and in-focus photos can sometimes be enough for us confirm a late blight infection.

Though we hate to say it, if the rainy conditions we’ve had so far this season continue, some of us will lose the battle against late blight. If that happens, you can find some suggestions for how to prevent your garden from being a source of infection for the whole neighborhood in the video What to Do if You Find Late Blight in Your Garden.

Good luck! And here’s hoping late blight doesn’t find you this season.

Lesions on leaves, stems, and fruit — it’s late blight in full bloom.

July 11, 2017
by Mary M. Woodsen
Comments Off on It’s Invasive Species Awareness Week all over the U.S.

It’s Invasive Species Awareness Week all over the U.S.

It’s Invasive Species Awareness Week — now. Pay it heed. Invasive species, it turns out, are a huge deal in the US, in New York. Everywhere, in fact.

Coping with invasive insects, pathogens and the like have cost, in the US as a whole, upward of … OK, I’m hedging already. Is it $40 billion a year? $120 billion, maybe? The estimates vary widely.

What about global losses?  Ahhhhh. Nailing those, especially vital ecosystem-regulating services, is where “difficult” morphs into “impossible,” for now and perhaps forever. It’s tricky, measuring something when it’s gone.

So what about the price here in New York? Unknown, though not for lack of trying.

Example: My admittedly quick-and-dirty search uncovered a 2005 report which  noted that costs for  eradicating Asian Long-horned beetle from New York City and Long Island had ranged between $13 and $40 million.

Killer beetle has distinctive markings. See something? Say something. Photo credit Kyle Ramirez.

Likewise in of 2005, New York spent about a half million dollars to control sea lampreys in lakes Ontario and Erie — with no end in sight.

More recently, in 2016, I learned that oak wilt — first discovered In New York in 2008 — has cost $500 grand to control. Some midwestern states spend over $1 million a year to control it. Pretty pricey if you ask me.

What helped here? Partly it’s the luck of the draw — oak wilt arrived decades ago, making inroads throughout the Midwest slowly but relentlessly. It can take time to recognize the true nature of  a pathogen — or most any invasive pest. Then it’s a catch-up game to stay on top of it. If you can.

On the loose all over the Midwest — and now here. Photo courtesy Iowa State Plant Disease Clinic.

New York saw what had happened elsewhere and has aggressively surveyed (good IPM!) and eradicated infestations quickly while still small. But that $500 grand price tag? Yow.

Still, the economic costs of losing every (yes, every) oak would far greater.

Yet to come — what to if you find Asian long-horned beetle, oak wilt, and the like.

June 19, 2017
by Mary M. Woodsen
Comments Off on It’s Pollinator Week. Read All About It.

It’s Pollinator Week. Read All About It.

It’s summer; the goldenrods will be blooming soon, with bumble bees buzzing around them. Photo courtesy David Cappaert.

When we think about bees, we mostly think about honeybees … a European native brought here by the very first colonists. Now honeybees are struggling, hammered by a constellation of 20-plus diseases and parasites — not to mention a range of insecticides and fungicides.

About 450 species of wild bees also populate our fields and gardens. They have similar problems. And they’re losing habitat.

This is serious business: we depend on pollinators for at least one-third of our food supply. Altogether, these pollinators boost New York’s economy by $1.2 billion.

And consider all those other critters: flower flies and hover flies, wasps, butterflies and moths; even hummingbirds — they are legion, they work hard for their living; they help too.

NYSIPM funds educational projects like this. Photo courtesy Jen Stengle.

What to do? For starters, we can make all these helpers even more at home in our fields and gardens.

Indeed, it’s through bringing together everything IPM knows about host and pest biology and habitat; about pesticides and their EIQs; about habitat protection and biodiversity — these are the things we excel at, and these are what we’re putting into play now to find the answers we need.

Ah … answers. Such as?

Since protecting non-target organisms is core to IPM, we helped advise the governor’s Pollinator Task Force in crafting a Pollinator Protection Plan — itself informed by a national strategy to promote the health of all pollinators. And our flagship IPM Annual Conference highlighted an IPM problem-solution approach for the 100 participants: farmers, consultants, beekeepers (but of course), landscapers, researchers, policy makers, greenhouse growers, and more.

Check it out — not only because you care about your health and your food supply, but because you care about this beautiful world we live in.

June 16, 2017
by Mary M. Woodsen
Comments Off on Tick Trickery and Lyme Disease: the Great Imitator? Sometimes.

Tick Trickery and Lyme Disease: the Great Imitator? Sometimes.

Remember the days when we could play with our tykes in tall grass near a wooded hedgerow? When we could wander at will through open meadows, picking wildflowers? When we could have impromptu picnics in the shade of tall oaks and basswoods deep in wild violets and leaf litter where a park blended into a tennis court, say, or a golf course rough? (Here, “rough” is a technical term used by the golf literati.)

Those days are gone. Now people in the Northeast and upper Midwest who live near anything green also live in a world that — subjectively at least — seems dominated by ticks. Blacklegged ticks (aka deer ticks) especially come to mind, but others are coming down the pike. (Lone star tick, anyone?)

The Southeast, eastern Texas, and the Pacific coast likewise see blacklegged ticks setting up shop.

Now — and remember this before you freak out — by no means does every tick vector Lyme disease or any of its coinfections, including anaplasmosis, babesiosis, and Powassan virus. The Centers for Disease Control (CDC) and National Institutes of Health (NIH) have a bountiful supply of carefully researched  information on these diseases.

CDC and NIH also keep tabs on long-term effects of Lyme — for instance, complications  like Lyme carditis and Lyme encephalopathy — that are important to understand.

And because Lyme can also mimic a considerable range of diseases — many less than pleasant — NIH and PubMed (the website is admittedly a bit of a slog) fund a considerable amount of research on these sorts of things.

Researchers might find, for instance, that what appeared to be ALS was actually  Lyme — for this patient, surely an enormous relief. A course of antibiotics and it was over. But if you find websites that link Lyme with upward of 300 diseases, best be skeptical until you can confirm the  science behind the claims that interest you most.

So let’s circle back to where we began.  Yes, you can still get your fill of nature. You can still hang out in your yard. You just need to know some basics. Prevention, in a word. That IPM mantra.

Prevent — well, most of us especially want to know how to keep those little buggers off us. So … how then? Well, consider the permethrin route. Permethrin is synthesized from a compound — pyrethrin — found in the seed cases of chrysanthemums. (Know that many plants include toxins to a lesser or greater degree — it’s the nature of nature. But that’s a whole other post.)

So take a hike over to Tick Encounter and learn all about treating your clothes, your shoes, whatever, with permethrin. Other search terms for permethrin, whether at Tick Encounter or elsewhere, might include “treat backpacks, tents, ground cloths …” You get the idea. But please — keep your antennae tuned for potentially bogus claims.

Want to learn everything you can about the ecology and biology behind ticks and Lyme disease? The Cary Institute for Ecosystem Studies is where you belong.

And if you’re perplexed by where “blacklegged tick” comes from when “deer tick” seemed to say it all — well, it’s worth knowing that deer aren’t the reservoir hosts; they don’t carry Lyme. Essentially it was a case of mistaken identity. Back in the day, when Lyme first erupted, researchers thought they’d discovered a tick new to North America; its common name became “deer tick.” A few years later scientists discovered that this deer tick was none other than the already-known blacklegged tick. There you have it and so it remains.

September 21, 2016
by Mary M. Woodsen
Comments Off on Trees and Drought Make for Less Colorful Fall (and the IPM Connection)

Trees and Drought Make for Less Colorful Fall (and the IPM Connection)

Many thanks to Paul Hetzler, CCE St. Lawrence County, for permission to use this piece.

It turns out that, in terms of fall foliage, the color of too dry is officially known as “blah.” This would undoubtedly be the least popular color selection if it was included in a jumbo pack of Crayolas. Basically, it is a jumble of faded hues with a mottled brown patina throughout. This year’s dry summer could mean that “blah” may feature prominently in Mother Nature’s fall hardwood forest palette.

Why would a prolonged lack of moisture affect autumn color? Let’s look at what makes leaves colorful in the first place. Among the things we learned — and probably forgot right away — in Junior High Biology is that leaves are green because of chlorophyll, the amazing molecule that converts light, water and carbon dioxide into sugar and oxygen. Its intense green tends to mask colors such as orange and yellow that are present in leaves in lower concentrations. When chlorophyll dies off in the fall, those “weaker” colors are revealed.

The Adirondacks in full autumnal glory — but not in the mega-drought of 2016.

The Adirondacks in full autumnal glory — but not in the mega-drought of 2016. Photo courtesy Sharp Swan.

It’s not like yellow and orange are just randomly painted on the insides of leaves, though. Molecules other than chlorophyll are involved in various metabolic pathways within a leaf, and they happen to be colorful. By comparison, we are boring. Our hemoglobin is red, at least in the presence of oxygen, but we are not as flamboyant on a cellular level as leaves are.

Red, however, is a horse of a different color where leaves are concerned. Trees spend energy that they would otherwise save for next year’s growth to make the molecule responsible for red. It is called anthocyanin, mostly because short words embarrass scientists, and it is “expensive” for trees to make. No one knows why trees do this. OK, there are some explanations out there, but they are so flimsy they don’t even hold up in the rain.

In wintertime, I make my own bread. Although quality varies because I never use a recipe, more than likely the bread would turn out worse than usual if I omitted water. Similarly, all the ingredients need to be there for photosynthesis to work properly. When water is in short supply, production at the sugar factory, also known as the chlorophyll molecule, drops off sharply.

Without sugars, many cellular processes slow or even stop. Damaged chlorophyll is not replaced, and that deep forest-green color starts to pale. Those yellow and orange molecules (xanthophylls and carotenes, if you are insecure about word length) also begin to disappear.

As trees dry out further, their leaves start to brown along their edges. This is called marginal scorching, not to be confused with marginally scorched, which describes my bread. In drought-prone locations with thin soils, some tree leaves will entirely brown and turn crisp, calling it quits for the year. This of course is not good for trees, because they are not able to plug up the vascular connections between leaves and twigs, making them prone to even more desiccation over the winter.

As if that isn’t enough sepia tones for one season, our sugar maples once again are looking tawdry due to yet another infestation of the native maple leafcutter. This is a tiny colorful moth whose newly hatched larvae eat circular patterns inside leaves, eventually getting big enough to emerge onto the leaf surface and excise little holes in it to make a mini turtle-shell case for itself. A single infestation causes only minor harm to the maples, but repeated infestations can weaken them somewhat.

Between marginal scorch, brown leaves, holey maples and a general shortage of leaf pigments, we might not get the brightest display this fall. Cool nights and sunny days tend to favor the production of red in the few tree species capable of producing it, and this could at least offset the brown tinge that infuses our woodlands at present. Here’s hoping for a good crayon selection this autumn.

The IPM Connection? Well, you can’t run the well dry trying to keep your trees happy. But worse yet would be thinking your trees have some horrid disease and it’s time to dash over to the garden center for a jug of fungicide. In this case you’ve got two fundamental IPM precepts to guide you now and for the future: an accurate diagnosis and preventive action.

  • Identify (i.e. diagnose) your problem before you act. Trees that look sick or pest-ridden could suffer instead from to a surfeit or lack of three critical things their fine feeder roots need: the oxygen, water, and nutrients. Because if those roots aren’t happy, neither is your tree.
  • Prevent the problem: learn which trees will work for your landscape and how to help them deal with the hand Nature deals them. Right plant, right place, proper care: these help reduce infestations and impacts of pests.

Check out this helpful guide.

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