Author Archives: Robin Simmen

About Robin Simmen

Robin Simmen is Community Horticulture Specialist for Cornell Cooperative Extension of Suffolk County. She can be reached at 631-727-7850 x215 or at rls63@cornell.edu.

Sample Soil Now for Healthier Landscapes Next Year

Spring is by far the busiest time for gardeners. Between selecting plants, starting seeds, and preparing beds, we often forget about what’s basic: the soil. Suddenly remembering, in April gardeners furiously submit handfuls of soil to our Horticulture Diagnostic Lab for testing, expecting immediate turnaround, and then realize, “What!? It takes how long for limestone to change the pH of my soil!?”

This is why autumn is the perfect time to start preparing your gardens for the growing season ahead. Submitting soil samples to us now allows you enough time to collect your samples properly, understand the test results, and if you need to make amendments to the soil, time for them to activate before next spring.

Using a soil auger makes collecting samples easy, but a trowel will work just as well.

Using a soil auger, shown above, makes collecting samples easy, but a trowel will work just as well. Photo by Robin Simmen.

Maintaining the proper soil pH is just as important for maximum crop yields as fertilizing, watering, and pest control. The decision to add lime to raise the soil pH and the amount to apply must be based on a soil pH test and the crop species to be grown. Do not guess. Some plants, like rhododendrons, azaleas, and blueberries as well as other members of the Ericaceae family grow best in acid soil (pH 5.0). Most vegetable garden plants grow best in soil with a pH in the 6.2 range. The recommended range for a lawn is between 6.0 and 7.0.

Instructions for taking a soil sample

First determine how many samples to take. Different gardens/beds, lawns, areas with different soil types, places where such amendments as limestone were added, areas with plants having different pH requirements, and good/bad areas should be sampled separately as described below:

  • In gardens or areas planned for new plantings where the soil will be turned under or rototilled, individual samples should be taken from the upper 6 to 8 inches of soil.
  • In established plantings or lawns where the soil won’t be turned under, individual samples should be taken from the upper 3 inches of soil.
  • Each soil sample should be comprised of 5 to 10 individual samples obtained by walking back and forth diagonally across the area to be sampled.
  • Use a trowel to dig a small hole to the desired depth. Remove a slice of soil from the entire side of the hole and place this in a clean plastic container. Repeat this procedure at each of your 5 to 10 random spots, and place the soil from these spots in the same container, discarding any stones, grass, or other debris.
  • Next, remove two 8-ounce cupfuls of the soil in this container and place them in a plastic bag. Secure the bag. This is your soil sample for that area. Mark the outside of the bag with an identification (i.e. #1, #2, or “A”, “B”, or “East”, “West”). Keep the identification simple.
  • Repeat this entire procedure for each additional garden, landscape bed, and/or lawn area you wanted tested.

You can find soil testing submission forms to accompany your samples on our website at http://ccesuffolk.org/agriculture/horticulture-diagnostic-labs. The cost of a soil pH test is $5 per sample; if you submit five or more samples, they cost $3.50 each. Mail or drop off your samples at 423 Griffing Avenue, Riverhead, NY 11901. Our office hours are Monday through Friday 8:30 a.m. to 4:30 p.m.

Sandra Vultgaggio is Horticulture Consultant for CCE Suffolk. She can be reached by email at sib7@cornell.edu or by phone at 631-727-7850 x387.

Rosemary for Remembrance

Rosmarinus officinalis is a wonderfully aromatic plant with a wide range of uses. An herb steeped in folklore and tradition, “There’s rosemary, that’s for remembrance,” Ophelia says to Laertes in Shakespeare’s Hamlet. The plant has long been used as a memory strengthener, and in Elizabethan times appeared at both weddings and funerals as a token of remembrance. Besides the beliefs that add to the lore of this beautiful plant, rosemary provides great culinary flavorings, is used in toiletries and potpourri, and appeals to gardeners as a simple decorative container plant. With all these accolades, its only drawback is that it cannot survive cold Long Island winters outdoors. With some preparation, however, you can ensure your rosemary plant will follow you indoors and out throughout the years.

In-ground rosemary thrives in coastal California, but not in colder Long Island gardens. Photo c Sandra Vultaggio.

In-ground rosemary thrives in coastal California, but not in colder Long Island landscapes. Photo © Sandra Vultaggio.

To understand how best to conserve your plant, consider where rosemary thrives. Its botanical name, Rosemarinus, comes from the Latin words ros, meaning dew, and marinus, meaning sea. “Dew of the sea” probably refers to the herb’s native habitat among the misty cliffs of the Mediterranean seaside. Rosemary is winter hardy to USDA Zone 8-10, just shy of our cooler, Zone 7 climate. The herb enjoys growing in light, slightly acidic, dry-to-medium, well-drained soils in full sun. Much like the lavender you may already grow, rosemary has very good drought tolerance and cannot abide wet, heavy soils that usually prove fatal to it.

If you intend to keep your rosemary plant alive during winter, bear in mind its Mediterranean home. Since we aren’t able to grow rosemary in our landscapes, keeping it in a pot is often better than planting it in the ground. A well-draining clay pot gives its roots the breathability they crave. Use a high-quality, lightweight potting mix, and consider amending it with additional perlite. This will aid in drainage and keep the media loose, which helps mimic the conditions where the plant grows naturally. Provide a water-soluble fertilizer every two weeks if the growing media doesn’t already contain fertilizer.

During winter, keep the soil in the pot evenly moist: not wet and not dry. A clay pot allows the soil to dry out sooner than non-porous pots do, so use your finger to test soil moisture and decide when to water. Water the plant deeply, allowing water to run through the pot and into the catch tray. Discard the water that runs through.

The two most important factors you must remember about growing rosemary indoors during winter is that it will not tolerate wet feet or dry air. Forced hot-air heat inside the home can dry out its foliage quickly, so misting the plant weekly is important. Keep rosemary indoors somewhere where it gets bright light but also stays on the cooler side.

Follow these tips, and come the spring thaw, your rosemary plant should still be thriving. Once all danger of frost has past, take the plant out of the pot, tease its roots apart a bit (cutting out a small portion of them if necessary) and add some fresh potting soil. Place the re-potted rosemary outdoors in a full-sun location for the remainder of the growing season, and enjoy its beauty again for another year!

Sandra Vultgaggio is Horticulture Consultant for CCE Suffolk. She can be reached by email at sib7@cornell.edu or by phone at 631-727-7850 x387.

Managing Landscapes Sustainably

Remember when autumn meant making a pot of soup, pulling out the leaf rake, and spending an afternoon raking leaves into backyard piles for kids and dogs to enjoy? Life in the fast lane has changed all that, degrading the quality of life on many fronts. According to Quiet Communities –a national non-profit organization dedicated to protecting our health, environment, and quality of life from the excessive use of industrial outdoor maintenance equipment—tasks once done manually are now often done with gas-powered machinery. A manicured aesthetic has become the new norm in many communities that barely tolerate even small amounts of leaves or debris. As a result suburban landscapes have lost critical “messy” habitat that insects and other vital species need to live, leading to a loss of biodiversity.

No one wants to breathe in the polluted air created by gas-powered leaf blowers. Photo c Quiet Communities.

No one wants to breathe in the polluted air created by gas-powered leaf blowers. Photo © Quiet Communities.

The deafening roar of gas-powered leaf blowers (GLBs) has replaced the “woosh, woosh” of the rake, and painful noise is just a small, if most noticeable, part of the trouble GLBs cause. Their motors send particulate matter into the air at 200 m.p.h., spewing forth dust, mold, pollen, pesticides, rodent feces, lead, arsenic, other heavy metals, fertilizers, fungicides, and herbicides right into our lungs. These particles aggravate asthma, bronchitis, emphysema, and allergies; in fact, particulates have recently overtaken second-hand smoke as the second greatest cause of lung cancer after smoking.

One GLB produces as much smog as 17 cars and blows 5 pounds of particulate matter into the air per hour, affecting the air of 8-14 neighboring properties. “Every time the leaf blowers are in our neighborhood, my son starts wheezing and has to use his inhaler,” said one father in Huntington, New York. Those are just a few of the reasons a group called Huntington C.A.L.M. (Citizens Appeal for Leafblower Moderation) has formed to educate local citizens about the harm caused by unregulated two-stroke Gas Leaf Blowers. The group’s goal is to limit the use of GLBs by commercial landscapers during summertime when more people are outdoors. Suffolk County received a grade of “F” for air quality for the last 14 years, and this group hopes to improve our air by placing a summertime restriction on GLBs in Huntington.

To learn more about how you can make healthier landscape decisions, come to CCE Suffolk’s Managing Landscapes Sustainably conference in Ronkonkoma on November 12. One of the speakers includes Jamie Banks, PhD, MS, Executive Director of Quiet Communities, an environmentalist and health-care scientist dedicated to promoting clean, healthy, quiet, and sustainable landscaping and agricultural practices.

Robin Simmen is Community Horticulture Specialist for CCE Suffolk. She can be reached at rls63@cornell.edu or at 631-727-7850 x215.

Native Plants Champion Biodiversity

Ever wonder whether it really makes a difference whether or not you plant native species? Do native plants do a better job of hosting local insect communities than their non-native counterparts? Now a University of Delaware study shows that not only are natives much better at sustaining local insects, planting non-natives actually compounds the problem of declining species diversity because non-natives support fewer herbivore species across our landscapes.

A yellow swallowtail enjoying a purple coneflower. Photo by Mary Howe.

A yellow swallowtail enjoying a purple coneflower at the Children’s Garden at Suffolk County Farm, part of the National Pollinator Garden Network’s Million Pollinator Garden Challenge. Photo by Mary Howe.

The research was conducted by Karin Burghardt and Doug Tallamy, who is professor of entomology at University of Delaware and author of the bestselling book, Bringing Nature Home. Together they published their findings in a recent issue of Ecology Letters: http://onlinelibrary.wiley.com/doi/10.1111/ele.12492/abstract To conduct their study, they planted imitation yards with different common garden selections of both native and non-native tree species, and then collected data over a three-year period, measuring the herbivore communities and species found on those plants.

Tallamy said that finding young herbivores on a plant is a good indication of how that plant is supporting the local ecosystem, as opposed to finding adult insects, which could be on a plant for a number of reasons, such as resting or looking for a mate. “The relationship between the adult and food is far weaker than the relationship between immatures and food, so when you find adults on the non-natives, it doesn’t mean that much. When you find immatures, that’s what you should be measuring,” Tallamy said. “Those are the plants that are creating those immatures, and so we do get significant differences between the immatures that are using native plants versus the immatures using non-natives.”

He also stressed that that native plants always do the best job per tree of supporting herbivore communities when compared to their non-native counterparts. This study expands the understanding of that fact by looking at whether that lower per tree diversity is magnified further by non-natives hosting more similar communities across trees species and locations.

Burghardt said the goal of the research was to understand how the composition of the plants that homeowners plant in their yards affects herbivore communities. “What the gardens we constructed for the study are trying to replicate are landscaping decisions that people might make if they wanted to support native insect communities that in turn support much of the diversity around us.”

Learn more about how what you plant affects biodiversity at the Long Island Native Plant Initiative’s biennial Native Plant Conference on Saturday, October 24, at Farmingdale State College. LINPI’s Registration Flyer includes a symposium agenda and list of speakers.

Robin Simmen is Community Horticulture Specialist for CCE Suffolk. She can be reached at rls63@cornell.edu or at 631-727-7850 x215.

Apply Now for Master Gardener Volunteer Training

CCE Suffolk trains Master Gardener Volunteers to provide the public with gardening programs and activities that draw on the horticultural research and experience of Cornell University. MG Volunteers receive research-based instruction and are kept up-to-date through continual exposure to the latest developments in environmental horticulture. In return, they agree to share their knowledge with neighbors by volunteering to do community service. After completing the training course and volunteering for 125 hours, they become certified as CCE Suffolk MG Volunteers. Suffolk County’s MG Volunteer Program, along with similar programs in other counties in New York State, is directly linked to Cornell University as part of its National Land-Grant College charter. This tie to Cornell provides MG Volunteers with state-of-the-art gardening knowledge.

A happy tribe of MG Volunteers keeps the Children's Garden growing at Suffolk County Farm.

A happy tribe of Master Gardener Volunteers keeps the Children’s Garden growing at Suffolk County Farm.

Anyone who enjoys gardening and has a desire to share knowledge and skills in their community can apply by October 31, 2015 to become a MG Volunteer. Every year hundreds of these service-minded folks from Suffolk County do the following:

  • Organize a Spring Gardening School for the public, including workshops, exhibits, and a plant sale
  • Table with gardening information at community events
  • Cultivate the land and teach youth at the Children’s Garden at Suffolk County Farm
  • Design and help maintain community beautification projects, demonstration gardens, community gardens, and school gardens
  • Offer gardening talks and classes at public libraries, schools, and for interested groups
  • Create and participate in programs for senior citizens, youth, and the physically and mentally challenged
  • Teach the proper care of lawns, shrubs, trees, and flowers, and how to grow fruits and vegetables
  • Install exhibits and provide gardening information at flower shows and events such as the Suffolk County Farm PumpkinFest and the Bayard Cutting Arboretum Fall Harvest Festival

The next training course for new MG Volunteers will be held in 2016, beginning February 3 and ending June 29. We are revising the curriculum and weekly schedule to provide more hands-on training and make it accessible to people who work Monday through Friday. Starting February 3, weekly Wednesday evening lectures will be held 5:30-8:30 p.m. at CCE Suffolk, 423 Griffing Avenue in Riverhead. Starting April 2, Saturday morning classes will also be held 9:00 a.m.-noon in the field (weather permitting) every other week at various locations from Amityville to Riverhead until the course ends June 29.

The cost of this comprehensive gardening course remains $375 with an additional $125 deposit, refunded upon completion of 125 hours of volunteer service. Download an application here.  For more information, please call or email me soon; the deadline is October 31.

Robin Simmen is Community Horticulture Specialist for CCE Suffolk. She can be reached at rls63@cornell.edu or at 631-727-7850 x215.

Late Blight on Long Island – Did We Dodge the Bullet?

While gardeners and farmers elsewhere, including upstate New York, have been battling late blight in 2015, so far it hasn’t been found on Long Island! At least, not yet . . . This is the first year since 2008 that this highly contagious and very destructive disease of tomatoes and potatoes hasn’t been observed here in spring and summer. Its absence means that on Long Island, we are successfully managing plant sources of the late-blight pathogen, Phytophthora infestans, in three ways by:

  • not planting infected potato tubers to grow new crops
  • not leaving infected potato tubers from previous crops in the ground or putting them in cull or compost piles
  • not planting infected tomato seedlings
We all dread seeing these symptoms of late blight appear on our tomatoes!

We all dread seeing these symptoms of late blight appear on our tomatoes! Photo by Meg McGrath.

But one source of late blight remains on the scene and continues to be a threat until frost: spores blown long distances by wind. Typically spores of Phytophthora infestans blow no more than about 30 miles, but their farther wind dispersal is possible. A Long Island outbreak of late blight in August 2007 was, I think, the result of a storm carrying spores here from Lancaster, Pennsylvania. And in October of 2002 and 2008, late blight made its first appearance of the year on Long Island. There have been reports recently of late blight in New Jersey, so we’re not out of the woods yet.

Here is when late blight was first observed on Long Island in recent years:

  • October 3, 2002
  • July 5, 2006
  • Aug 26, 2007
  • October 3, 2008
  • June 23, 2009
  • June 18, 2010
  • June 24, 2011
  • May 29, 2012
  • July 25, 2013
  • June 20, 2014

Do you want to know where late blight has been reported in the United States this year? Check out www.usablight.org. Anyone can sign up on this website to get an alert by text or e-mail when a report has been logged nearby, so you can be one of the first to know when late blight has been found on Long Island. But realize your plants could be the first affected; therefore, signing up for alerts is not a substitution for looking for symptoms at least once a week. My own garden plants were part of the August 2007 outbreak!

Considering the potential impact of late blight, everyone who grows tomatoes and potatoes is responsible for inspecting their plants for late blight, reporting it when seen, and managing affected plants to minimize its spread. Photographs and information about late blight are posted on my website at: http://livegpath.cals.cornell.edu/gallery/tomato/tomato-late-blight/

If you see symptoms you think might be late blight (rather than one of its imitators, also shown on my website) call our Horticulture Diagnostic Lab at our hot line at 631-727-4126 from 9 a.m. to noon, Monday through Friday, where Alice Raimondo and Sandra Vultaggio, our Horticulture Consultants, can help determine whether you do, indeed, have late blight, even this late in the year.

Dr. Meg McGrath is Associate Professor at Cornell University’s Long Island Horticulture Research and Extension Center in Riverhead, New York, where she conducts research and extension activities to help farmers manage diseases.

Tomato Troubles? There’s an App for That

As Cornell University’s vegetable pathologist doing research at the Long Island Horticulture Research and Extension Center (LIHREC) in Riverhead, NY, I’ve seen a lot of sick tomatoes over the years, and I’ve been posting photographs of what I’ve seen on my website: http://livegpath.cals.cornell.edu/gallery/. When not at work, I’m an avid home gardener, too, so I have first-hand experience with the diseases popping up in Long Island gardens. In fact, many photographs on my website were taken at home.

Septoria leaf spot symptoms usually first appear on the lowest, oldest leaves after fruit start to ripen.

Septoria leaf spot symptoms usually first appear on the lowest, oldest leaves after tomatoes start to ripen.

This year my tomatoes have Septoria leaf spot, which started on one plant and has been slowly spreading to others. The spores of this fungal pathogen, Septoria lycopersici, are spread by splashing water. It hasn’t rained much this summer, and I usually water at the base of plants rather than use an overhead sprinkler, but the few rains we’ve had spread the pathogen a lot. Septoria gets into a garden when seed containing the pathogen or infected seedlings are planted, or a windy rainstorm moves it from a nearby infected plant. Once in a garden, this pathogen survives overwinter in tomato debris; hence the recommendations to remove infected plant debris and to rotate the areas where you grow tomatoes. Other diseases and disorders I’ve seen on my garden tomatoes include anthracnose and blossom end rot (both every year), drought stress on leaves, leaf mold, powdery mildew, and late blight, all of which appear on my website.

Small dark brown spots with tan centers containing very tiny black specks called pycnidia (spore structures) are characteristic of Septoria leaf spot.

Small dark brown spots with tan centers containing very tiny black specks called pycnidia (spore structures) are characteristic of Septoria leaf spot.

Recently some colleagues and I at the American Phytopathological Society, including Dan Gilrein and Margery Daughtrey from LIHREC, developed a new app for smart phones called Tomato MD. It costs $2.99 and is available for both Apple and Android phones. Learn more about it here: http://www.apsnet.org/apsstore/shopapspress/pages/apps.aspx

This interactive reference tool is set up for fast identification of tomato problems, based on symptoms of root, leaf, stem, and fruit. The goal of the app is to move you quickly through the most difficult part of dealing with a sick plant: what’s wrong and what is causing it. The app includes an index of nearly 30 diseases and insect disorders, an extensive photo gallery of the most common problems, and a list of diseases according to their characteristics. Tomato MD does more than just help with identification; management tips are included, too.

For more help in identifying what’s wrong, take a look at my website (above), then read our online fact sheets about dealing with tomato problems, which can be found here: http://ccesuffolk.org/gardening/horticulture-factsheets/vegetable-diseases. If you’re still stumped, call our Horticulture Diagnostic Lab at our hot line at 631-727-4126 from 9 a.m. to noon, Monday through Friday, where Alice Raimondo and Sandra Vultaggio, our Horticulture Consultants, are available to answer all your horticulture questions.

Dr. Meg McGrath is Associate Professor at Cornell University’s Long Island Horticulture Research and Extension Center in Riverhead, New York, where she conducts research and extension activities to help farmers manage diseases.

Buff Up Your Conservation Buffers

Because Long Island is surrounded by water, responsible residents strive to keep pesticides and fertilizers from polluting our coastal and drinking water resources. And as stewards of our land, we need to preserve as much habitat for wildlife as possible. One way to accomplish both goals is to plant garden or conservation buffers. These small pieces of land with permanent vegetation help control pollution while providing undisturbed habitat for wildlife. Examples of buffers include riparian buffers, small wetlands, shallow water areas, herbaceous and woody windbreaks, contour grass strips, living snow fences, and field borders.

Garden buffers like this one at Cornell Plantations in Ithaca can be used to filter polluted run off from parking lots.

Garden buffers like this one at Cornell Plantations in Ithaca can be used to filter polluted storm-water run off from parking lots. Photo © Robin Simmen

Although you may view them primarily as pleasant landscape features, buffers quietly prevent soil erosion, improve soil and water quality, enhance fish and wildlife habitat, reduce flooding, conserve energy, and ultimately conserve biodiversity. By capturing up to 75 percent of flowing sediment and by enhancing infiltration, buffers trap heavy metals. When properly installed and maintained, they can remove up to 50 percent of pesticides and nutrients from polluting coastal waters!

In addition to providing wildlife habitat (increasing the number and diversity of birds and butterflies) and creating corridors for their movement, buffers are attractive, low-maintenance, sustainable alternatives to traditional turf. Water moves more slowly through shrubs and other buffer plantings as compared to turf, thus reducing your irrigation needs. Conservation buffers can also improve your quality of life by reducing noise from the street and odors from garbage.

An added benefit is that buffers help reduce flooding. They also help stabilize streams, enhance biodiversity by providing micro habitats, and decrease and then stabilize water temperature. Fluctuations in water temperatures and warming can be very deleterious to fish and other aquatic creatures important to the stream food chain.

A shallow water area or a small wetland is a place where water depth is usually less than 2 feet with no more than 10 percent of the entire area being over 4 feet deep. These wet areas may be seasonal in nature, such as vernal pools, so you might be tempted to “dry ‘em out or fill ‘em in,” but DON’T DO IT! Not only is it often illegal to do so, but such spots are of particular importance to certain plants and animal species that depend on transient moisture for parts of their life cycles, e.g. reproduction or nesting.

To learn more about how to construct a conservation buffer on your property or how to evaluate your existing landscape, please join me and Joann Gruttadaurio, Senior Extension Associate Emerita, Cornell University, on October 15, 2015, 9:00 a.m. until noon, at the Suffolk County Farm for a hands-on workshop on how to “Buff Up Your Soil and Garden Buffers.” The cost is $30, and preregistration is required. Click here to download the registration form.

Dr. Tamson Yeh is CCE Suffolk Turf Use and Land Management Specialist. She can be reached at tsy3@cornell.edu or 631-727-7850 x240.

Best Way to Water Your Lawn

Question: I water my lawn every day, but it still looks like it’s drying out and turning brown. What is the correct way to water?

Answer: Usually there’s plenty of rain on Long Island during April, May, and sometimes well into June, but this year we weren’t so lucky. And summer rainfall has not been forthcoming. Most lawns need an inch or so of water each week to stay green, which is approximately how much moisture they lose weekly through evapotranspiration.

I suspect you are running your sprinklers for twenty minutes or so daily. Unfortunately, this means you are wasting lots of water and not helping your lawn. A brief daily shower only moistens the grass blades and doesn’t deliver enough water to the turf roots, which is why your lawn is going into drought stress.

Daily watering resulted in the drought-stressed lawn at the top of this picture. Compare it with the next-door neighbor's healthy lawn at the bottom, which receives one-inch of water just once a week.

Daily watering led to the drought-stressed lawn at the top of this picture. Below it, the next-door neighbor’s green grass receives only an inch of water once a week.

The best way to water your lawn with an inch of water is to soak it just once a week, which may take several hours depending on your water pressure and sprinkler heads. You can determine how long your system takes to supply one inch of water to your lawn by setting several empty tuna cans inside the spray pattern of your sprinklers and watching until they fill up to one inch; or you could buy a few inexpensive plastic rain gauges.

Late summer storms often supply ample amounts of water. As summer winds down, keep track of how much rainfall you get; then adjust your irrigation accordingly. Learn more about correct watering practices by looking at Suffolk County’s Healthy Lawns, Clean Water website, which discusses this in greater detail: http://healthylawns.suffolkcountyny.gov/lawn/watering.htm

Alice Raimondo is Horticulture Consultant for CCE Suffolk. She can be reached at aw242@cornell.edu or 631-727-77850 x335.

Gypsy Moth Defoliation across Long Island

After decades of very little gypsy moth activity, we are seeing “outbreaks” again this year. Many areas of Long Island have experienced extensive defoliation from gypsy moth caterpillars this summer, and other areas in New York and around the region (CT, RI, MA, PA) have also been affected. Homeowners are learning the hard way that touching the hairs on these caterpillars can be quite irritating, so minimizing contact with them is important, especially for those with sensitive skin.

Photo credit: USFWS/James Appleby

Photo credit: USFWS/James Appleby

Long Island’s NYS DEC Forester is aware of the situation, particularly since it is affecting forest areas and not just those in residential landscapes. At this point nothing can be done; gypsy-moth damage is about finished for the year. The adult moths are now active and egg masses are very obvious on tree trunks, suggesting we’re in for another round next year (there is only one generation a year). Trees that have been heavily defoliated should, however, be protected from a second wave of defoliation from other insects this summer, such as the orange-striped oak worm, which we sometimes see in August. One defoliation weakens trees, but a second one in the same season can kill them or make them more susceptible to opportunistic pests like two-lined chestnut borer. You’ll want to protect trees from defoliation next year, too, which would also weaken them. Now is a good time to examine cultural conditions around affected trees – are they getting too much or too little water? Do you see soil compaction, root competition, or root disturbance around them?

Our Horticulture Diagnostic Lab is a good place to get information on helping trees recover from gypsy moth defoliation and on management options to reduce the risk of damage next year. Call the Lab’s hot line at 631-727-4126 from 9 a.m. to noon. Options might include systemic treatment (trunk injection) where foliar pesticides aren’t an option, or foliar sprays where spray drift and getting tree adequate coverage are not problems. A fact sheet about the gypsy moth is available on our website: http://ccesuffolk.org/gardening/horticulture-factsheets/tree-and-shrub-insect-pests (Note: this fact sheet is for homeowners; CCE Suffolk has additional information for arborists and other professional applicators).

Many years ago a natural insect-killing fungus was introduced to control the non-native gypsy moth. This fungus has done a good job of regulating its population since 1988, but this year’s exceptionally dry spring probably contributed to the fungus’ limited impact this summer (we did see some evidence of it at Heckscher State Park and elsewhere). Unfortunately the fungus tends to “kick in” after some defoliation is already apparent, but when spring conditions are wet, the fungus can be highly effective in minimizing the problem the following year.

Late this summer we’ll be better able to gauge the risk for 2016 based upon counts of gypsy-moth egg masses. These counts are usually done by forest entomologists and professional foresters. The procedure is outlined in a document posted at the NYS DEC website (http://www.dec.ny.gov/animals/83118.html), providing an estimate of expected severity in the coming year. Homeowners can also check around their properties to see what might be in store locally for next year. Since the newly hatched caterpillars can blow around to other areas, infestations outside your property can also be a threat and should be taken into consideration. If you see lots of tan, felt-like egg masses in your area (including adjacent forest trees) then expect another year of significant damage in 2016.

If you have valuable, susceptible trees, you might want to plan accordingly by engaging a consulting arborist this fall or winter for spring treatment to deter risk of heavy defoliation. There are a variety of options, including some organic products and other products used as trunk injections (noted above) where spray drift or adequate coverage are issues. You can remove and destroy egg masses on trees during late summer through early spring; however since the caterpillars can migrate from other areas it doesn’t provide absolute protection in large outbreaks.

Dan Gilrein is Extension Entomologist for CCE Suffolk. He can be reached at dog1@cornell.edu or at 631-727-3595.