From the Horticulture Diagnostic Lab: Emerald Ash Borer Found in Suffolk County

Photos of trees in varying stages of health are not a new thing for the Horticulture Diagnostic Lab to receive. Homeowners often contact us wanting a diagnosis of their sick or “dying” tree. I recently responded to an email from a homeowner from the north fork of Long Island, inquiring about borer holes on three deciduous trees, and I requested he send photos. When the photos arrived, the injury to the trees was unlike anything I had seen before; extensive woodpecker activity called “blonding” (see photo below).

The trees have furrowed bark, opposite branching and a somewhat weeping habit, which is characteristic of ash trees, and although I wasn’t able to see the emergence holes from the photos, my heart sank. This had to be the workings of an insect called the Emerald Ash Borer (EAB), which up until now had not been found out in Suffolk County. Confirmation of the tree species as ash and identification of EAB followed just a few days later by our local Cornell Entomologist Dan Gilrein. EAB has arrived.

With no known sightings of this insect in any other parts of Suffolk or Nassau counties, one wonders how did this insect found its way all the way out to the north eastern part of Suffolk County with no stops in between? Ash trees do not make up our native forests here on Long Island, but varying species of ash (genus Fraxinus), have been planted as street trees in many locations and planted on homeowner properties as well. The movement of infested firewood, much like other invasive insects such as the Asian Longhorned Beetle, or diseases such as Oak Wilt, is the most likely answer. Human activities provide the transportation for these hitchhikers.

In the community where the insect was found, many of the homes are second homes or vacation homes, so perhaps firewood was brought in from another location where EAB is well established. I’m writing this to hopefully make more people aware that it is illegal to move firewood more than 50 miles from its source and that by law untreated firewood cannot be brought in to New York State. For more information about the specific regulations pertaining to moving firewood you can click on the following link to the New York State Department of Environmental Conservation website; https://www.dec.ny.gov/animals/44008.html. Don’t contribute to the growing spread of destructive invasive pests. Protect our trees!

At the time of this writing it isn’t known the extent of the EAB infestation here in Suffolk County, but as always our Horticulture Diagnostic lab is here to help! Emerald Ash Borer can also attack a related species of tree called the fringetree which is a very ornamental flowering tree. For specifics on this highly destructive insect pests please feel free to visit the New York State Department of Environmental Conservations website for their EAB fact sheet here;  https://s3.amazonaws.com/assets.cce.cornell.edu/attachments/34998/EAB_DEC_early_detection_brocure.pdf?1546628049.

This beetle is difficult to detect before extensive damage has been done, so if there are valued ash trees on your property you should likely consider protecting them with the appropriate pesticide. The New York State Department of Environmental Conservations press release regarding the finding of the Emerald Ash Borer can be found here;  http://www.dec.ny.gov/press/115854.html.

If you suspect you may have EAB on your property or are having a problem with you trees, feel free to give us a call. You can find our contact information here; http://ccesuffolk.org/gardening/horticulture-diagnostic-labs.

Article by Alice Raimondo, CCE Suffolk Horticulture Consultant

 

From the Horticulture Diagnostic Lab: Boxwood Blight

With the year drawing to a close and cold weather settling in, our diagnostic lab in Riverhead remains busy. This year has been a banner year for boxwood blight, with the lab seeing over 85 positive samples come in. The humid weather throughout the summer, followed by a particularly rainy fall created the perfect environment for this disease to thrive in our landscapes.

Before you go run out to your boxwoods to see if they’re okay, know that if you haven’t brought in any new boxwood, pachysandra or Sarcococca (sweet box) plants into your landscapes since 2011, your plants are probably okay. If you are particularly fond of the boxwoods on your property, you will  want to familiarize yourself with some of the common symptoms:

  • Black or dark brown leaf spots
  • Black or dark brown steak-like lesions on stems that almost resemble markings from a permanent marker
  • Sudden and dramatic leaf-drop.
  • Green stems that are defoliated.

We have some very helpful links and photos for you to check out on our website:

Photos above are courtesy of Mina Vescera, CCE Suffolk Nursery and Landscape Specialist. Photo to the left, Boxwood Blight spots; and on the right, Boxwood Blight canker

To prevent this disease from striking your boxwood, we recommend not planting new boxwoods, or, if you do, only purchase plants from a trusted source. Only use clean pruning tools when shearing or pruning your boxwood. Tools can be disinfected by cleaning with a 10 percent bleach solution (9 parts water to 1 part bleach)- wipe off tools to remove debris, soak for 10 minutes in 10% bleach, and rinse in clean water before use. Leaves that fall from boxwood are small and sticky – be vigilant of leaves attached to shoes, gardening gloves and tools. Make sure your boxwoods are sited in the appropriate conditions: full sun with good air circulation, irrigated with soaker or drip hoses and not overhead irrigation. Boxwoods are more likely to become infected in continuously wet conditions.

If your boxwoods are looking unthrifty, it doesn’t necessarily mean they are infected with boxwood blight. Contact us at the Horticulture Diagnostic Lab with photos and samples. Our publication here, Photographic guide of Boxwood Pests & Diseases on Long Island, will help you troubleshoot the common problems we encounter.

Should your boxwood fall victim to boxwood blight, your best course of action would be to pull out the plants and destroy them. Fungicides may help protect plants from new infections but they are costly and diligent applications are necessary and not always successful. Severely pruning back plants can be helpful, but with the slow growth-rate of boxwoods, you may be looking at a sad plant for a long time. Until effective management solutions are discovered, your best bet will be to think outside the box…wood. You can find some good alternatives on our factsheet.

Sandra Vultaggio, CCE Suffolk Horticulturist

photo courtesy of Margery Daughtrey, Cornell University

 

“Climate Change, Science, Communication and Action” Online Course from Cornell University

Cornell University Civic Ecology is once again offering a 6-week online course on “Climate Change, Science, Communication and Action” starting this week, 9/11/18. Please share with anyone you know may be interested! Registration remains open this week at:
 
Suffolk County residents who enroll in this course are welcomed to join our local Suffolk CCE Community Action group, where we will provide educational resources and additional in-person trainings that address Gardening in a Warming World.
Contact Donna Alese Cooke at dmc72@cornell.edu to learn more about our local Suffolk CCE Community Action group, and the upcoming free in-person classes that will be available to Suffolk County residents participating in the “Climate Change, Science, Communication and Action” online course. 

What are those Webs in the Trees?

Fall webworm is all around on Long Island now.  Our Diagnostic Lab is getting many complaints about a wide variety of trees and shrubs with lots of webbing, defoliation and browning leaves.

According to Sandra Vultaggio, Horticulturist in our CCE Suffolk Diagnostic Lab, this pest has been particularly successful this year in part due to the high humidity we’ve experienced. Since this is a late-season pest it does not tend to affect the health of the tree. It is more of an aesthetic issue when the brown leaves and webbing occur. For this reason we do not often recommend pesticides. Once the caterpillars are finished feeding, which takes roughly 6 weeks, they will fall to the ground to pupate over winter. It may be wise to do a thorough fall cleanup of leaves and debris around the trees this year.

Dan Gilrein, Extension Entomologist adds that some herbaceous plants are affected as well. Some may confuse this with gypsy moth, which doesn’t produce webbing and is not active this time of year, or (eastern) tent caterpillar, which is active in spring mainly on cherry and apple, ornamental varieties of these, and some related plants. Fall webworm is a native insect and its populations go in cycles. It’s wide host range includes over 400 plants. This particular ‘outbreak’ is the largest he has seen, though similar (short-lived) population explosions have been observed elsewhere. Fall webworm levels were high in parts of the Adirondacks last year, for example, but have since collapsed for the most part. Dan is not sure know why these population swings occur, but they probably have to do with direct and/or indirect impacts of environmental conditions on  the insect, its natural enemies, and possibly its hosts.

While the webbing and damage are very ostensible, the actual harm to the plants is probably much less.  At this time of year the foliage has done most of its ‘work’ and will be declining soon. There might be some concern for plants that are being heavily defoliated, were in poor condition, or just recently planted, but generally plants should grow normally next year. The good news is this insect has many natural enemies (one author refers to it as a ‘parasitoid hotel’), so the numbers are expected to be much less next year. Ways to deal with this are:

  • Remove webbing and caterpillars by hand which will improve the appearance immediately.
  • Prune out infested branches. This is the last alternative, as it can damage the plant, spoil the appearance, and open wounds.
  • Contact a consulting arborist or landscape professional for assistance, who can assess and handle the job.

Photo courtesy of Master Gardener Holly Sisti

Be on the Lookout for these Vegetable Garden Diseases!

Look out for these garden diseases! See symptoms? Please report!

Occurrence of a couple important diseases of vegetables and basil is monitored in the USA every year to be able to inform growers when they need to be prepared for them to develop in their crops. Their occurrence is variable and impact is great, thus the importance of monitoring, which is done primarily by plant pathologists working with growers. Gardeners can access this information, thereby also benefiting, and they can play a very important contributing role by reporting when these diseases occur in their gardens. Some gardeners already have been! I have lots of photos to help with identifying these plus other diseases at: http://blogs.cornell.edu/livegpath/gallery/ and information about them at http://blogs.cornell.edu/livegpath/extension/for-gardeners/. Make sure to take photos to document your report.

Late blight of tomato and potato. Occurrences are mapped at http://www.usablight.org/. At this webpage anyone can sign up to receive alerts when late blight has been confirmed near them; the alert system is not just for growers.

Late blight on tomato

Downy mildew of cucumber, squash and other cucurbits. In addition to information about occurrences, at http://cdm.ipmpipe.org/ there is a map-based forecasting system predicting where the pathogen is likely to develop next. There is also an alert system gardeners can utilize.

Downy mildew on cucumber

Downy mildew of basil. Reporting presently is done to a spreadsheet at https://docs.google.com/spreadsheets/d/1lHTfaVYxjjr7CxbEJiv8qgYmB5VdMFdT_4ehfjQrc5U/edit#gid=0  A map-based webpage is being developed similar to that for the other two diseases.

Downy mildew on basil

Take advantage of these great resources, and please contribute reports to increase the value of monitoring and our knowledge about occurrences of these important diseases.

Dr. Meg McGrath is an Associate Professor at Cornell University’s Long Island Horticulture Research and Extension Center in Riverhead, New York.

Not sure of the disease on you vegetable plants? Contact our Horticulture Diagnostic Lab and drop off a sample for diagnosis. For current hours, visit: http://ccesuffolk.org/

 

 

New Online Master Gardener Volunteer Training

No need to wait until you retire to take the Master Gardener Training program! New this fall, CCE Suffolk will be offering an online, hybrid training program that is designed for you to learn at your own pace, while easily fitting into your busy schedule.

Starting in September of 2018, the program will include all of the horticultural topics and hands-on training needed to become a Master Gardener Volunteer for Suffolk County Cornell Cooperative Extension. Monthly weekend in-person trainings will take place one Saturday each month from September 2018 through March 2019. Now is the perfect time to take the first step, and join our very dedicated group of expert gardeners!

See our new brochure to learn more about the Master Gardener Volunteer program.

Download the application for the 2018-2019 training here.

Questions? you can email Donna Alese Cooke at dmc72@cornell.edu or call her at 631-727-7850 ext 225

Master Gardeners volunteering at Spring Gardening School

 

 

Landscape Trees with Beautiful Bark

Sycamore bark

With spring rapidly approaching there’s no better time to appreciate the silhouettes of our trees, especially those with attractive bark. This is a valuable ornamental feature often overlooked. While you are likely familiar with some of the larger trees that have striking bark, such as American or European beech, American sycamore or London Plane tree, there are many trees suitable for smaller landscapes which will catch your eye.

Japanese stewartia

Perhaps you are familiar with Stewartia psuedocamelia, or the other Stewartia species which have white camellia-like flowers in the early summer. But did you know that as they mature they develop an exfoliating bark in a patchwork of copper, tan, olive and lavender? Stewartia spp. are typically pest free and offer fall color too. Every yard should have one! Another tree offering bark in similar colors are the Crape Myrtles, Lagerstroemia indica hybrids. Crape myrtles are widely known for their late summer flowers in shades of pink, red, purple and white. When looking for a crape myrtle for your landscape select varieties best suited for our colder winters and then chose a flower color.

River Birch Bark

 

Maybe you have a wet site where many trees do not do well. I have just the solution for you, and it has attractive peeling bark to boot! The tree I’m referring to is called a river birch, Betula nigra. Young trees have papery bark in shades of cream, salmon, orange brown, and cinnamon brown which peels freely. As the tree matures the trunks become dark reddish brown to gray-brown in color with plate-like scales. River Birch also boasts resistance to the bronze birch borer, a devastating pest of many other beautiful birch trees.

A lesser known tree with highly ornamental bark is the Paperbark cherry, Prunus serrula. Much like most other flowering cherries, its white flowers are short lived and it may be prone to disease and insect pests, but the bark is incredible! I came across this tree in the New York Botanical Garden and was wowed! The bark is a glistening coppery red-brown, looking more like polished copper than living bark. I’m still contemplating including this one in my own landscape despite the pest management it will likely require.

Birch bark Cherry

Acer griseum

Mature Kousa dogwood bark

 

Before leaves and flowers emerge this spring, get out and really look at your trees. Botanical gardens and arboretums are a great place to see some of these trees and others that are especially beautiful in winter. Take notes and photos. Consider planting one or more of these trees with beautiful bark to give your landscape four season appeal!

Article and photos by Alice Raimondo, CCE Suffolk Horticulture Consultant

Register for the 2018 Spring Gardening School

Join us for Suffolk County’s annual Spring Gardening School on Saturday, April 14, 2018, 8:30 a.m. to 4:00 p.m. Organized by Master Gardener Volunteers for the last 36 years, this beloved event kicks off the growing season for hundreds of gardeners who gather together for a day of learning and fun.

Spring Gardening School 2018 will be held at the Riverhead Middle School in Riverhead, NY. All classes are taught by Master Gardener Volunteers and Cornell Cooperative Extension Educators. The day consists of workshops held during three sessions and offers classes for beginners to advanced gardeners. This year a keynote address on “The High Line: Lessons for Your Garden” will be presented by Roxanne Zimmer Ph.D., Master Gardener Volunteer from Peconic.

You can sign up for such classes as School & Community Gardens 101, Gardening in Deer Country, Edible Landscaping, Gardening in Small Spaces, and many, many more. This year, you can choose to create hands-on take home projects such as Botanic Art (see project below), Nature’s Colors in Your Hands (plant dyes), Make & Bake Herb Bread & Butter, Floral Arranging, and The Art of Bonsai.

The fee to attend is $65 per person ($60 early bird, before March 1st), which includes free soil pH testing, a plant diagnostic clinic, gardening exhibits, and an early plant sale from some of the finest nurseries on Long Island; continental breakfast, delicious boxed lunch, raffles, and door prizes. Preregistration is mandatory; first come is first served.

Classes fill quickly! Download the brochure here which has the registration form to mail back to us. We look forward to seeing you there!

Attracting Birds in Winter

Keep your gardens alive with color through the winter by attracting songbirds to your yard.  Feeding birds throughout the winter not only benefits the birds, but is a great hobby for gardeners to keep us active and engaged with the outdoors. Heavy winter snow events can cover up much of bird’s natural food sources, forcing them to seek out what humans may have left out for them.

Downy Woodpecker, photo by Sandra Vultaggio

There is nothing quite like seeing a bright red Cardinal against a snowy backdrop. When feeding birds, you can try to be specific as to which birds you would like to attract, or very simply provide a mixed seed which will attract an array of birds. Different feeders are attractive to some types of birds, while discouraging others, and specific foods and seeds will attract some birds and not others.

Northern Cardinal, photo by Sandra Vultaggio

Hard wire mesh feeders are attractive, often painted with bright colors and will attract many of your smaller, clinging birds like Chickadees, Nuthatches and Tufted Titmice. These are great for larger seed blends like black oil sunflower seeds and safflower seeds. They often stay stocked for a while since the birds need to pull seeds out individually. They also tend to leave the ground below much cleaner.

A platform feeder is great for any bird, but especially attractive to the larger birds: Blue Jays, Mourning Doves and Flickers. You will often find Dark-Eyed Juncos using these types of feeders as well. Any type of seed and nut mix will work well on these types of feeders. It’s fun to watch the individual personalities as the different species interact in the open space.

Hopper-type feeders are great for keeping seed fresh and protected from the elements. These are a great option if you don’t intend to go out to fill the feeders often, as they can hold quite a bit of food.

A popular food source for birds in winter is to provide suet. Suet is a high-energy food source that will attract woodpeckers. Peanut butter is also a great fatty food source. You can search for fun DIY feeder projects using peanut butter and seed that will be sure to attract lots of different hungry visitors.

Tufted Titmouse and White-breasted Nuthatch. Photo by Alice Raimondo

Ready for some real entertainment? Get yourself a peanut wreath. It is so much fun to watch the blue jays and squirrels bickering with each other trying to remove the peanuts from the spiral of wire.

Blue Jay under a peanut wreath, photo by Sandra Vultaggio

Prolonged freezing temperatures can make water sources scarce, so providing fresh water is a surefire way to attract birds and other wildlife to the yard. Often times you’ll attract a more diverse set of species with water than you would with seed. You can provide a fresh water source all winter long if you purchase a water de-icer or an ice-free birdbath. These contraptions do not heat the water, but simply keep the water from freezing – typically down to 20 degrees Fahrenheit. Most of the quality re-icers on the market need to be plugged in and generally cost $1-2 per month to run, depending on how cold the weather is.

Eastern Bluebirds enjoying a heated birdbath. Photo by Alice Raimondo

When you feed birds outside, you may quickly find that the larger predatory birds are just as hungry as the songbirds. Hawks will often perch in high trees near feeders, waiting for an unsuspecting dove. For this reason, it may be a good idea to hang feeders near shrubs or other brush material so the birds will have quick access to shelter if needed. In the same way, be aware that feral cats have a way of staking out backyard birdfeeders.

Sometimes you do not have to invest any money at all to attract birds to your yard throughout the winter. You can simply provide habitat for them by minimizing your fall cleanup. Leaving sticks and other small debris lying about for wildlife to pick up and use as needed. Or pile up larger branches and debris in a discrete corner of the yard where wildlife can use it as shelter through the winter Allow spent flower heads to stand throughout the winter for finches to pick through. Consider leaving the dried stalks of ornamental grasses to stand all winter to provide habitat and shelter for wildlife and insects. In the spring, birds will often take pieces of the grasses to assemble their nests.

Following some of these tips will ensure that looking out of your window in the winter will not just make you long for springtime, but appreciate the beauty that each season brings us.

Black-Capped Chickadee, photo by Sandra Vultaggio

by Sandra Vultaggio, CCE Suffolk Horticulture Consultant

Caring for Holiday Plants

It’s that time of year again, when we either give or receive plants as gifts and tirelessly try to keep them healthy throughout the year in hopes they may bloom once again. Because these plants are grown specifically for the holiday season, there are some tips and techniques you can use to keep them from ending up in the compost bin and looking beautiful year-round.

The poinsettia, Euphorbia pulcherrima, is a popular potted plant at this time of year, providing color throughout the holiday season. Newer poinsettia cultivars are long-lasting in contrast to those available a few years ago. When purchased, poinsettias should be in prime condition, should be well shaped plants with dark green foliage and bracts free from defects.

To care for Poinsettia, soil should be kept moist at all times, but not excessively wet. Water when the soil begins to feel dry and apply enough to the surface until it runs through the drainage hole. For best results, do not allow foliage to wilt between watering. Keep poinsettias away from cold drafts and excessive heat, otherwise this may cause foliage and bracts to wilt from rapid water loss.

Poinsettias are among the most difficult plants to re-bloom in the home. To learn more about propagating poinsettia and proper care for re-bloom next year, our fact sheet on “Care of Holiday Plants” includes more information on Christmas Cactus, Cyclamen and other blooming holiday plants available this time of year.

Adapted from Resource The Selection, Care, and Use of Plants in the Home, by Charles C. Fischer and Raymond T. Fox, Cornell University, 1/90.