New York State IPM Program

January 23, 2018
by Mary M. Woodsen
Comments Off on One bug at a time: how biocontrol helps you, even in winter

One bug at a time: how biocontrol helps you, even in winter

Sure it’s winter. But many greenhouse growers work year-round. And what’s this about biocontrols? In fields, orchards, vineyards, and greenhouses—especially greenhouses—biocontrols are the predators and parasites that keep pests in check, minus the pesticides. What’s special about greenhouses? They’re where pests consistently find plenty of food, just-right temperatures, and little to stop them from bounding out of control. The linchpin that drives the search for alternatives to pesticides? Consumer demand.

Looks like sawdust—but it’s really bran infused with the tiny eggs or larvae of beneficial insects.

Which is where biocontrols fit in. These critters evolved to eat pests for breakfast, lunch and dinner. But there’s a learning curve involved. You can’t bring in the good guys and call it a day. Use a broad-spectrum pesticide and you’ll do them in. Which is why an Extension educator in the six-county New York Capitol District crafted a series of workshops to help growers get the hang of that seemingly simple IPM practice: biocontrol.

Since seeing is believing, growers attended a series of workshops where they saw start-to-finish biocontrol in action. What did they learn?

Examples

  • how to distribute marigolds throughout their greenhouses as a thrips (bad guy) magnet
  • how to apply a nematode drench to control the fungus gnats that eat roots
  • which 17 biocontrols can collectively cope with 21 bad guys
  • how the IPM Greenhouse Scout app helps you choose among them

Little sachets are another way greenhouse growers can introduce those tiny, good-guy bugs to the posies that need them.

As for consumer demand? People worry about pesticides on their posies. In theory, biocontrol appeals to them. But they haven’t seen it in action. If they see bugs, any bugs, good guys included—they might worry. That’s why a simple, colorful flier is part of the package, helping growers bring the message back to their base—their customers.

January 5, 2018
by Joellen Lampman
Comments Off on Ticks and the freezing weather

Ticks and the freezing weather

“That is a bracing cold, an invigorating cold. Lord, is it cold!” – Sheldon Cooper

It is inevitable that when the temperatures drop below zero we are asked “Will this extended period of extremely low temps kill off ticks?”

First, the bad news. We do not expect the cold to directly affect black-legged or dog ticks as they are adapted to this climate and will survive just fine under the blankets of leaf litter and snow.

The good news, followed by some bad news, is we are basically looking at a reversal of the large quantities of ticks in 2017 that began in 2015 when oaks in New York underwent a mast seeding event. (In simple terms, there was an enormous amount of acorns on the ground across the state. If you want to delve more deeply into the mast year phenomenon, check out Mechanisms of mast seeding: resources, weather, cues, and selection.) Abundant quantities of food led to a large quantity of small mammals in 2016. Large numbers of small mammals led to a substantial number of ticks in 2017. Researchers at the Cary Institute of Ecosystem Studies have decades of field research to back up the relationship, and lag time, between mast years and Lyme disease risk.

Which brings us to the current frigid weather, and probably even more importantly, the ice under the snow, and how it will impact small mammals. Animals that have a harder time finding food are more likely to (in order of lessening consequences) die of starvation, succumb to other stresses such as disease or predation, fail to mate, give birth to fewer young, and give birth less often. In a nutshell, there should be fewer hosts come spring. And fewer hosts eventually lead to fewer ticks. Good so far.

But there is some bad news, too. During the time of high tick numbers and fewer small mammal hosts, each of us, and our companion animals, are at greater risk of coming into contact with questing ticks. So as soon as the temperatures rise into the mid-30s (and we know you will be out enjoying the veritable heat wave), ticks will be questing and we need to Steer Clear of Ticks and the Diseases They Carry — the IPM Way.

I am afraid the search for a reason to fully embrace the cold continues.

November 1, 2017
by Mary M. Woodsen
Comments Off on It’s (still) tick season — and will be evermore

It’s (still) tick season — and will be evermore

Sorry to bring up a sore subject, but it’s still tick season. And will be all year round. What … during winter? Really? Yes. But for starters here’s your pop quiz:

A tick’s lifespan is

  • three months
  • ten months
  • twenty-four months (that is, about two years)

The best way to remove a tick is to

  • swab it with nail polish
  • hold a hot match to its behind
  • pull it straight up with fine-point tweezers

Even 15 million years ago, it was tick season. Trapped in amber, this tick carries Lyme-causing bacteria. (Photo credit Oregon State University.)

But back to our intro. Here’s the scoop: an adult female that hasn’t yet managed to grab hold of a large animal (think deer — or person) to get that all-important blood meal (can’t lay eggs without it) doesn’t want to wait around till a sunshiny summer day next year, because by then its number is up. Besides, the mice, chipmunks or birds it fed on earlier in its life cycle have only so much blood to go around. So that tick stays just below the soil where tall meadow flowers or low shrubs grow. Waiting. Waiting for a thaw barely long enough for it to scramble up one of those stems.

Waiting for the cues that tell it a warm-blooded animal is at close range. An animal that might be you.

And now for a look at our quiz. A tick’s lifespan? Your answer is (drumroll) C: upward of two years. Here’s how it works: Ticks spend a lot of time in dormancy, aka diapause. Eggs are laid in spring, tucked away out of sight. If some critter doesn’t find and eat them, they’ll hatch during summer as larval ticks (seed ticks, they’re sometimes called). Larval ticks are not infected with Lyme when they hatch — indeed, they’re pure as the fallen snow.

Meanwhile if likely hosts — those mice, chipmunks or birds — wander by, the ticks latch on. And if a host is already infected with Lyme disease or any of its nasty co-infections, those larval ticks, pure no more, are infected too.

Look close and you’ll see that spring, summer, fall, winter … every season is tick season. (Image credit Florida Dept. Health)

Larvae that make it this far morph into nymphs, and it’s diapause season again as the nymphs wait it out till the following spring. Assuming these ticks are now carriers —and about 25% will be — spring is the worst time of year for us. Because these ticks are tiny enough (the infamous poppy-seed stage) that they’re easy to overlook. If you get bit, ipso facto — you get Lyme (and quite possibly a co-infection too).

Things slack off in late summer as surviving nymphs enter a diapause that lasts till the following spring. But you can’t let down your guard, since by mid-fall through winter you’ve got those adult ticks to consider. The good thing (if “good thing” there is)? While half of these sesame seed-sized ticks are infected, they’re also easier to spot and remove.

Our second  quiz item? If any of these strike you as valuable folk wisdom, strike the valuable part and know it ain’t so. Nail polish? Matches? Don’t even think of it. Those first two items are just likely to tick that tick off — and it’ll vomit its gut contents into you in its hurry to get out. That is, if it can get out quickly; if it’s really drilled in, it has downloaded a cement-like substance to anchor itself. It takes some doing to disengage, however persuasive the nail polish, burnt match, or myriad other folklore remedies. (Twisting it is another no-no that comes to mind, mainly because someone asked me about it mid-way through this post.)

Pointy tweezers, held right against your skin and gripping the mouthparts, are the way to go. (Image credit tickencounter.org)

If you value your health, get yourself some pointy tweezers, sold for needlepoint and other crafts, and carry them with you always in your bag, backpack, or whatever you haul around. Grasp that tick as close as you can get to your skin and pull steadily. Did its mouthparts remain glued within? Not to worry — the tick will feed no more. And before too many days go by, your exfoliating skin (that’s when the top layer of skin cells drift away) will exfoliate them in turn.

With ticks, prevention can include everything from doing routine tick checks to wearing repellent clothing when you’re outdoors — regardless the season. And you can’t do much better than this for advice about dressing right.

Meanwhile here’s your catchphrase: 32, ticks on you. “32” as in 32°F. Stay watchful — and stay safe.

October 10, 2017
by Matt Frye
Comments Off on Steer Clear of Ticks and the Diseases They Carry — the IPM Way

Steer Clear of Ticks and the Diseases They Carry — the IPM Way

These days if you live near anything green — a suburban development, however humble or high-class; a neighborhood park where shrubs and meadow flowers grow — best you’d read up on ticks, be they black-legged ticks (aka deer ticks) or lone-star ticks (so named for the silvery white dot on the female’s back). While you’re at it, read up on Lyme disease and its suite of co-infections, some nastier even than Lyme.

And know this: no magic spray or treatment will eliminate ticks.

Researchers are investigating area-wide tick management options (The Tick Project) and working to understand how habitat management (The Tick Management Handbook; Japanese Barberry Control Methods) and host management (mice, deer) affect tick populations. But it’s up to you to protect yourself — knowing that prevention is the best cure.

  1. Wear tick-killing clothing. Buy over-the-counter permethrin spray and spray it on your clothing and gear. Used according to the label, permethrin binds to the material and can kill ticks, mosquitoes and other pests following a lethal exposure. Do-it-yourself treatments can remain effective for up to seven washes. Also consider buying pretreated cloths or sending your outdoor socks, pants, and shirts for professional treatments. These can be protected for up to 70 washes.

    Follow label instructions for do-it-yourself clothing treatments.

  2. Use repellants. DEET, picaridin, oil of lemon eucalyptus and IR3535 all repel ticks. The percentage of active ingredient on the label indicates how long that product will be active in the field. For more on choosing the right repellant see our previous post, “Understanding over-the-counter sprays for mosquitoes and ticks” (June 2, 2015) and this guide from Consumers Reports.
  3. Ticks wait for a passing host on vegetation or in leaf litter. Staying on trails can reduce your exposure to ticks.

    Recognize and avoid tick habitat.Tick species differ in where they prefer to hang out. The blacklegged tick (transmits Lyme disease) is found at adult knee-height and below in wooded or brushy areas. When hiking, stay on the trail and away from these areas. If you’ll be in tick habitat, take precautions by wearing long pants tucked into your socks and a light-colored shirt tucked into pants. These steps make it more difficult for ticks to get to your skin. If you’ve treated your clothing with permethrin, this can also increase the exposure of the ticks to the acaracide — the tick-killing substance.

  4. Steer clear of hitchhikers. 

    Isolate exposed items in large, zippered plastic bags to avoid bringing ticks indoors.

    Ticks can be carried on clothing or gear that you used outdoors — gear that you haven’t used permethrin or a repellent on. True, ticks don’t survive long in most homes because of low humidity, but still — you’re safest if you change your clothes and place exposed items in a large, zippered plastic bag in an entryway. Put them in a clothes dryer and run on high heat for 20 minutes. The tumbling action of the dryer and the high heat kill ticks and similar critters. [Note: don’t wash clothes first. Even the hottest cycle might not kill ticks, and it increases the drying time needed.]

  5. Check for ticks. Taking all these steps doesn’t mean you will avoid ticks 100% of the time. Perform daily tick checks even if you haven’t been outdoors in a day or so. Get to know the marks on your skin and recognize new ones. New marks that, if you touch them, just happen to have legs.
  6. Remove ticks safely. Only one method has been officially evaluated for its ability to safely remove ticks — using sharp tweezers, grab a tick as close to the skin as possible and gently pull up. Other methods could increase the risk of acquiring a tick-borne disease. To learn more, see our post “It’s tick season. Put away the matches.
  7. Protect your pets.

    Grooming after outdoor activity with a fine-toothed brush can remove ticks in pet fur.

    Just like people, pets can encounter ticks and acquire tick-borne disease. If your pet goes outdoors, it should have some protection against ticks. TickEncounter describes some of the options available for your pets, including oral and spot-on medications as well as collars. Speak to your veterinarian about the best option for protecting your pet against tick bites. Regular grooming with a fine-tooth comb after being outdoors can help to remove ticks that have not attached to your pet’s skin.

Additional Resources:
What’s Bugging You? tick page
Other tick-related posts

September 21, 2017
by Mary M. Woodsen
Comments Off on It’s Hay Fever Season — and the Culprit Unmasked

It’s Hay Fever Season — and the Culprit Unmasked

[OK … so this isn’t strictly IPM. But it does shed light on a glorious native plant that gets a bad rap for making the allergy-prone among us miserable — and its weedy relative, found in city and country alike, that’s to blame. An IPM solution? Prevention, for one — education about weeding weedy city lots before ragweed flowers.]  

It’s late summer and we are awash in brilliant oceans of mustard-yellow goldenrod blooms. At the same time, hay fever symptoms are ramping up.

As goldenrod becomes the dominant wildflower on the scene, an increased pollen load in the air is making life miserable for those who suffer from allergies. Because of this correlation, it seems logical to blame goldenrod for your red itchy eyes, sinus congestion, sneezing, and general histamine-soaked misery.

Got hay fever? Don’t blame goldenrod. Photo Steve Burt, Creative Commons.

But there is an easy way to tell for sure if goldenrod is to blame — a one-question test: Have you noticed a lot of bees up your nose recently? If yes, then goldenrod might be guilty. If no, there is another culprit lurking about.

As one of the most abundant blooms of late summer and early autumn, this native wildflower is for many insects, including numerous bee species, a vital source of nectar as well as nutritious pollen.

Unfortunately, this latter item has given goldenrod a black eye among many allergy sufferers.

But consider this — goldenrod isn’t common in vacant city lots. And lots of hay fever suffers live in cities. Besides,  goldenrod can’t be guilty because its pollen is very heavy. That’s a relative term, I suppose, since it is light enough for bees to carry it around. Yet in the pollen realm it’s heavy—and is also very sticky—and can’t be blown far from the plant.

For goldenrod pollen to trigger an allergic response, someone or something would have to deposit its pollen directly into your schnozz. And in general, bees are not in the habit of doing so.

Will the real hay fever specialist please stand up? Photo Krzysztof Ziarnek Kenraiz, Creative Commons.

So who’s to blame for the spike in late summer allergies? Surprisingly, the culprit is goldenrod’s cousin, ragweed, although it doesn’t behave at all like its golden relative. Ragweed, another native plant, is also in the aster family, but unlike goldenrod it churns out loads of very light pollen.

Just how light? Ragweed pollen can remain airborne for several days, and significant quantities have been found as far as 400 miles out to sea. Ragweed easily colonizes vacant city lots, where a single ragweed plant can produce a billion pollen grains to fly on the breeze and make you sneeze.

Yep, this is the stuff that stuffs you up.

One reason we don’t suspect ragweed is that its blossoms are dull green and look nothing like a typical flower. It’s as if they’re trying not to attract attention. Because it’s wind-pollinated, it has no need to advertise with bright colors and sweet nectar to entice pollinators.

Turns out it’s way easier to attract wind than bees.

Most ragweed species—there are about 50 of them—are annual, but they come back year after year from the copious seeds they produce each fall. Ragweed will keep billowing allergens until the first hard frost, so let’s hope it’s not too much of an extended season this year. And let’s spread the word about goldenrod to spare it further false accusations.

[Our thanks to Paul Hetzler for his kind permission to use this story. Hetzler is a horticulture and natural resources educator with Cornell Cooperative Extension of St. Lawrence County. Unedited original at https://blogs.northcountrypublicradio.org/allin/2017/09/10/dont-blame-goldenrod-for-your-bless-you-hay-fever-symptoms/]

 

August 10, 2017
by Mary M. Woodsen
Comments Off on Invasives IPM Update: ALB and oak wilt stand-ins

Invasives IPM Update: ALB and oak wilt stand-ins

Back in mid-July, during Invasive Species Awareness Species Week, we wrote a post using asian longhorns beetle (ALB) and oak wilt as stand-ins for the multitude of invasive species already here or knocking at our doorstep.

And we promised we’d tell you what to do should you suspect these two big-time baddies might be in the neighborhood or down the road — info you can draw from to report other invasives too.

Of course, first you have to know what the symptoms of ALB and oak wilt are. After all, an accurate ID is key to IPM. So zip over to the NYS Department of Environmental Conservation’s website for their ALB and oak wilt info.

Killer beetle has distinctive markings. DEC tip line: 866-702-9938. Photo credit Kyle Ramirez.

You’ll learn that trees under attack by ALB often have wilted foliage and canopy dieback. But here are the main things to look for:

  • Round exit holes, ⅜” to ½” in diameter. Beginning from late July on, those mark where adults are exiting trees. Stick a pencil in there to see if the hole is at least an inch deep.
  • Round depressions — egg-laying sites, ½“ — in the outer bark.
  • Sap oozing from egg-laying sites and exit holes.
  • Sawdust (aka frass) in small mounds at the tree’s base or branch crotches.

To corroborate what you’ve seen, take pictures of the holes, including something for scale — a coin or ruler, for instance. Be sure to note the location — intersecting roads, landmarks or GPS coordinates.

Then call the ALB tip line: 866-702-9938.

You’ve got other options too, but best you go to DEC’s website for them.

On the loose and here at last. DEC tip line: 866-650-0652. Photo credit ISU.

And oak wilt? It’s scary. This killer pathogen — Ceratocystis fagacearum — can take down a red oak in as little as a few weeks. Where tree roots overlap, it can travel via those roots from one oak to the next, the next … sometimes taking down miles of forest. Then too, fungal mats from under their bark and exude a sweet odor that attracts bark or sap-feeding beetles, which carry the spores from one tree to another, another — sometimes miles away.

Put together, the red and white oak tribes include dozens of species. Many are common to the Northeast. But white oaks are luckier; years can pass before they die. Why? Mainly because the wilt doesn’t suffuse through the root systems of neighboring trees, nor does a sweet-scented spore mat form under the bark. But it kills them all the same.

Yes, it might seem odd that an organism first found in Iowa and Texas took more than 50 years to get to New York. But such is the way with nature. At any rate, it’s here now, an implacable foe — and all the lessons learned in the Midwest help bolster ours.

Our space is limited, so for now let’s just consider red oaks. Scarlet, blackjack, and pin oak belong to this clan. The main things to look for?

  • Outer leaf edges turn a tan, coppery, or reddish brown, progressing toward the mid-veins.
  • Branch dieback starts at the top of the tree’s canopy and works its way down — quickly engulfing the entire tree.
  • Leaves suddenly wilt in the spring and summer and often fall while still partly green.

Think you’ve seen oak wilt? Call 866-650-0652. If you need to prune trees —and even if you don’t — check out DEC’s two-minute video. Because regardless — this is one of those situations where citizen awareness and involvement matter. A lot. Prevention (key to IPM) and protective zones, for instance — learn more about them while you’re on DEC’s website too.

Solutions — chemical or biocontrol (especially biocontrols)? If only. But we’re just not there yet.

August 1, 2017
by Bryan Brown
Comments Off on Abandoned fields: Weedy disaster or IPM opportunity?

Abandoned fields: Weedy disaster or IPM opportunity?

Farmers across New York have been struggling with the overabundance of rain this year — meaning that some cornfields never got planted. The result? Weeds have really taken off.

So what? If there’s no crop for weeds to compete with, what’s the danger?

Weeds make seeds, lots of seeds, which could cause a disaster in the next few crops. My research shows that plots where weeds went to seed had 10 times as many weeds the following year. If any of those weeds are herbicide resistant, they’ll drop thousands of herbicide-resistant seeds into farm fields.

But there’s hope. As of late July, most of these weeds are still flowering and haven’t set seed yet. Mowing is a great option to quickly prevent (classic IPM tactic!) the flowering weeds from setting seed. Yes, after mowing those weeds may send up new flowers. So it is important to kill them with herbicides or tillage before planting summer cover crops (check out the Cornell cover crop decision tool) or fall plantings of forage or winter grains.

Bryan Brown, Ph.D. stands in an unplanted cornfield where weeds have gone unmanaged

Doesn’t look like corn, does it? Weed seed production could cause disaster in future crops. But most of the weeds have yet to set seed — so management options are still on the table.

For many problem weeds, most seeds will die in the first couple years in the soil. So if you can keep weed seeds from entering the soil this year, you can really cut down the number of seeds in your soil. In IPM, prevention is the name of the game.

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.

July 6, 2017
by Mary M. Woodsen
Comments Off on Biocontrols for Invasive Pest Help Save Mountain Forests

Biocontrols for Invasive Pest Help Save Mountain Forests

Biocontrols — organisms that help keep serious pests in check — are a key component of IPM. And sometimes they’re the only hope. Consider the lovely, lacy-needled hemlock tree, a member of the pine family.

“The hemlock is a foundation species in our forests,” says Mark Whitmore, a forest entomologist at Cornell University and a founder of the New York State Hemlock Initiative. “It occupies the base of the food web and is a critical species in the habitat it helps create.” But the hemlock is under threat by a killer pest so tiny it verges on microscopic.

“Take no prisoners” describes the woolly adelgid’s modus operandi.

Whitmore’s checklist? Hemlocks

  • moderate stream water temperatures for trout and many other animals
  • provide a buffer for nutrient inputs to maintain water quality
  • stabilize shallow soils, especially in steep gorges
  • shelter plants and animals — especially important in winter, when they help moderate temperature swings
  • offer critical habitat for migrating neo-tropical birds
  • provide large-scale watershed quality and biodiversity protection

Hemlocks also help ring the registers when fishing season opens. How can that be? Well, trout fishers’ contribution to New York’s economy is nothing to sneeze at. And research in the Delaware Water Gap showed that streams draining hemlock forests support an average of 37 percent more aquatic insect taxa — including many that provide food for trout — than do streams flowing through deciduous forests.

About that pest — it’s the hemlock woolly adelgid, native to Asia. This tiny pest has already done a staggering amount of damage to hemlock stands in the southern Appalachian Mountains, leaving scarred remnants of once-lovely ravines and mountainsides in its wake.

Now it has gained a foothold — in some cases, a stranglehold — in forests throughout the Northeast.

Losing those hemlocks? “Catastrophic” could be the right word to sum up the consequences. “The hemlock is the only tree in eastern North America that can do its job so well,” said Kathleen Shields, project leader for biological control with the U.S. Forest Service in a 2002 article in Forests Magazine. “If we lose the hemlocks, there’s no other tree to fully take its place.”

The waxy white balls that cover every twig mark this tree as a goner. (Photo Forestry Images)

But if you’ve even heard of the hemlock woolly adelgid you’re way ahead of the game, because the hemlock woolly adelgid isn’t much to look at. In fact, you’d have to scrape off the waxy white ball it hides in, then squint into a 10-power loupe — a special type of magnifier — just see it.

And because it rarely travels fast or far (for most of its life cycle, it doesn’t even move), the adelgid might not strike you as a particularly menacing pest. Until, that is, thousands of them suddenly set up shop on every hemlock tree in your neck of the woods.

How can this be? Well, there’s the adelgids’ prodigious reproductive capacity. In fact, a single adelgid’s offspring can, by the season’s end, potentially contribute upward of 5,000 adelgids — and every last one is female — to the hemlock’s pest burden.

Then there’s the adelgid’s life cycle: it breeds during the winter. Most insect predators don’t. And factor in that those predators aren’t looking for a bug that resembles little more than a ball of wax.

Sure, it took 50-plus years for the woolly adelgid to reach upstate New York — but it’s here now. Meanwhile, Whitmore has been working against this day for many years.

The only good thing you could say about the adelgids implacable pace is that it’s given Whitmore time to test and release predators which help provide the backbone of a suite of predators that could soon keep the adelgid at bay in New York.

The first predator out of the box was Laricobius nigrinus, a type of tooth-necked fungus beetle, released in 2009. In 2015, Whitmore released two species of silver fly, both from the genus Leucopis. Altogether, these predators should flank the adelgids for a more complete biocontrol.

This larval silver fly slides into that waxy ball, where it feeds on adelgids — and nothing else.

Of course, work like this has to be a team effort, and Whitmore has worked in concert with colleagues at the U.S. Forest Service and the University of Massachusetts-Amherst on one project; the U.S. Forest Service, University of Vermont, and Oregon State University on a second.

And of course — each new biocontrol must feed on its host prey and nothing else. It takes long, patient vetting over many years to be sure a biocontrol won’t itself become a pest.

Whitmore’s work is built around classic IPM techniques, especially monitoring (are they in your neck of the woods yet?) and biological controls. The countless hours Whitmore has put into this earned Whitmore an “Excellence in IPM” award in 2015.

“Mark’s meticulous research brings together all the strengths of IPM; of truly integrated pest management,” says Jennifer Grant, director of NYS IPM “But it’s his passion for his work that really makes the difference. Whether it’s volunteer citizen-science groups or the New York State Department of Environmental Conservation, people look to Mark for the information and expertise they need.”

“He speaks for the trees.”

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