New York State IPM Program

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.”

April 13, 2016
by Mary M. Woodsen
Comments Off on No Greenhouse, No Grow Light? This Advice Is a Fun Read Anyway

No Greenhouse, No Grow Light? This Advice Is a Fun Read Anyway

Now, I don’t have a greenhouse or even a grow light on my windowsill. But sometimes IPM ornamentals specialist Elizabeth Lamb’s  posts are so much fun to read that I just want to share them with the world.

From now on, it’s Elizabeth’s voice you’re hearing.

I just figured out how to hyperlink in my emails.  I’m quite the dinosaur!  Click on the blue words to get the link if you are a dinosaur like me.

This generalist eats more than just western flower thrips — it'll eat the thrips specialists like Neoseiulus cucumeris too. Photo courtesy natural-insect-control.com.

This generalist rove beetle eats more than just western flower thrips — it’ll eat the thrips specialists like Neoseiulus cucumeris, too. Photo courtesy natural-insect-control.com.

It’s a rove beetle eat predacious mite world out there.  Great information from Sarah Jandricic (OMAFRA) on how to keep your thrips beneficials from eating each other! Also, a little early nursery scouting might be in order – things they are already seeing in Ontario – Bagworms, Viburnum leaf beetle egg masses, and gypsy moth egg masses.

Lots of information from Tina Smith at UMass and Leanne Pundt at UConn
Keeping an eye on those calis. Calibrachoa troubleshooting for diseases and disorders. Or tackling thrips with bios and pesticides  (remember to check for NYS labels on any pesticides)  Lots of other resources linked to this report.

While you’re at it, be nice to your nematodes.   This article makes the point about not storing nematodes in a refrigerator that is opened frequently.  Another temperature shock could be mixing chilled nematodes with too warm water.  Not sure we have the research on this yet, but it makes sense.

What are those strange lumps?  It could be crown gall – found on some lobelias this spring. It is caused by a bacterium and can be spread by water splashing, although it needs an entry point to get into the plant.  No good control so add it to your scouting list.

Do you have a pH or EC (electrical conductivity) meter stashed in your greenhouse that you last used last season?  It probably needs to be recalibrated.  Have you ever done that?  Here’s how! And to keep Margery happy – lovely photos of Thielaviopsis – and how to avoid having your own.

Where have all the archived updates gone?  Well, NYS IPM is in the process of getting a new website and we consolidated all the updates into one blog to archive them  Coming soon.

’Tis the season for greenhouse information — from my email to yours.  Have a good week!

Grow greenhouse crops — or for that matter, Christmas trees? Want to learn more? Give Elizabeth Lamb a shout at Elizabeth M. Lamb <eml38@cornell.edu> and she’ll subscribe you. You can, of course, opt out anytime you want.

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