Monthly Archives: August 2015

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.

Join the Million Pollinator Garden Challenge

The Million Pollinator Garden Challenge (MPGC) has been launched by the National Pollinator Garden Network, an unprecedented collaboration of national, regional, conservation and gardening groups to support the President’s Executive Strategy to “Promote the Health of Honey Bees and Other Pollinators.” MPGC is a nationwide call to action to preserve and create gardens and landscapes that help revive the health of bees, butterflies, birds, bats, and other pollinators across America. The goal is to move millions of individuals, kids, and families outdoors and help them make a connection between pollinators and the healthy food people eat.

MGPC logo 2MPGC wants people like you to register your gardens through their Pollinator Partnership and thus be added to the map they’ve created in support of this campaign. Along with a handful of other gardens on Long Island, the Children’s Garden, which is maintained by Master Gardener Volunteers at Suffolk County Farm, has been registered and is on the map, which appears in the link below.

To meet the criteria for registering, your pollinator garden should:

  • Use plants that provide nectar and pollen sources
  • Provide a water source
  • Be situated in a sunny area with wind breaks
  • Create large “pollinator targets” of native or non-native plants
  • Establish continuous bloom throughout the growing season
  • Eliminate or minimize the impact of pesticides

For more information and to join MPGC, visit http://millionpollinatorgardens.org

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

Best Plants for Attracting Ruby Throated Hummingbirds

Question: What are the best plants to grow for attracting ruby throated hummingbirds? I put up a bird feeder but was told that having the right plants is really important.

Answer: Yes, growing the right plants is critical for attracting these little jewels to your yard. These flowers provide not only the nectar the birds need but also habitat for all the little insects they like to eat. Best of all, flower nectar doesn’t require cleaning and refilling like bird feeders do!

Bee balm is a favorite flower of hummingbirds in my yard. Photo c Alice Raimondo

Bee balm is a favorite flower of hummingbirds in my yard. Photo © Alice Raimondo

Some of the best plants for landscaping for hummingbirds include the following (there are others plants that hummers can’t resist, but here are the plants they go nuts for in my yard):

  • Trumpet honeysuckle, Lonicera sempervirens
  • Cardinal flower, Lobelia cardinalis
  • Bee balm, Monarda didyma ‘Jacob Cline’
  • Anise-scented sage, Salvia guaranitica ‘Black and Blue’
  • Cuphea, Cuphea ‘David Verity’

On Wednesday, September 2, 2015, you can join me and my colleague Sandra Vultaggio for a presentation and tours about gardening for the ruby throated hummingbird. We’ll start at 3:30 p.m. with a PowerPoint presentation about this magical little bird, including how to attract them to your backyard and keep them coming back year after year. Then take a tour of two local backyard gardens to witness these natural jewels within garden habitats we designed just for them. The cost is $30. Click here to register for the hummingbird workshop and tour.

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

Managing Mile-a-Minute Weed

Mile-a-minute weed, Persicaria perfoliata, is a highly invasive annual vine appearing on the East End and other parts of Long Island. Its triangular shaped leaves are very distinctive and easy to identify. The weed is invading natural areas, residential yards, and landscapes. It thrives in areas of partial shade but can survive in full sun; mile-a-minute can potentially invade and establish itself in many environments. It is often found on the edges of residential properties near woods and sometimes on the periphery of field nurseries. It has also been spotted growing on the beach in different locations.

This site was infested by mile-a-minute seed that Hurricane Sandy carried  here.

This site was infested by mile-a-minute weed carried to Long Island by Hurricane Sandy.

Mile-a-minute weed has several commonly used nicknames: Asiatic tearthumb, climbing tearthumb, and devil’s tail. These monikers describe the sharp downward-curved prickles or spines that grow on the vine’s stem and petioles. Any attempts to hand pull this weed without wearing heavy leather gloves quickly illustrates why tearthumb is one of its names. Its spines act like claws that enable the vine to attach easily to nearby vegetation. This adaptation allows it to grow straight up towards open areas of tree or shrub canopy without having to waste energy by twining like other plants.

This rapid upward growth is the reason for its other common name: mile-a-minute. It takes advantage of most of the growing season on Long Island to produce multi-branched, thin-stemmed vines that are loaded with attractive blue fruit. When ripe, individual shiny black seeds are contained within a fleshy fruit that is very easily knocked off the vine. The seeds spread to new sites via migrating birds and other wildlife. Because the ripened fruits are so easily dislodged, hand pulling the vines after fruits begin to form in late July is not recommended. Leaving the vine alone in late summer and fall is a better option than trying to remove it from a site.

Immature and ripe mile-a-minute fruit in late July are easily dislodged.

Immature and ripe mile-a-minute fruit in late July are easily dislodged.

Recent research has shown that even immature green fruits can eventually mature off the vine to produce viable seeds for re-infestation. That leaves the months of May, June, and most of July to use cultural practices like hand pulling, string trimming, and mowing to suppress/control this weed. Because it has an annual life cycle, removing young plants has a very reasonable chance of significantly reducing the population. If mature plants are hand pulled after late July, the vines should not be placed directly into compost piles or other areas where the viable seeds can remain a threat. The pulled vines should be put under a tarp or landscape fabric until the fruit is no longer viable.

In addition to cultural practices, the NYSDEC recently approved a 2(ee) recommendation for the herbicide glyphosate (Accord XRT II, EPA Reg. No. 62719-556) for post-emergent control of mile-a-minute vine in non-crop areas. Because glyphosate is non-selective, it should be used only in areas where no desirable vegetation could be exposed to drift. However, in such areas where many seedlings are growing, using this herbicide can be an efficient way to control young plants.

Beneficial weevils eat the leaves of mile-a-minute weed.

Beneficial weevils eat the leaves of mile-a-minute weed.

Since 2004, a biological control has been released to help suppress this weed. Developed by Dr. Judy Hough-Goldstein at the University of Delaware, a small weevil, Rhinomomitus latipes, was found to feed on the leaves and stem of mile-a-minute without eating other desirable plants. On eastern Long Island the weevil has been evaluated since 2012 through controlled releases of it in areas infested with mile-a-minute. The weevil has also found its way here from surrounding states that use it to manage this weed. The weevil begins to feed on mile-a-minute leaves in early spring and continues all season. It lays eggs in the plant stem, which the subsequent larvae weaken as they develop and begin to feed. The adults overwinter in the leaf litter at the ground surface.

Unfortunately, there is a lot more weed than weevil, so we need to continue to increase the weevil population here. Funding cuts have meant CCE Suffolk must now purchase the formerly free weevils. We are hoping to develop a program that would not depend on re-introduction of the weevil every year. These beneficial weevils may play an important role in helping eradicate this scourge from our landscape before it becomes better established on Long Island.

Andrew Senesac is Weed Science Specialist for CCE Suffolk. He can be reached at afs2@cornell.edu or 631-727-3595. 

Stop Blossom-End Rot from Ruining Vegetables

There’s nothing like putting your heart and soul, sweat, and tears into creating a beautiful vegetable garden only to have your fruits turn out all wrong. Over the coming weeks, I’ll be writing about some reasons your vegetables might not shape up to be county-fair contestants this year. Blossom-end rot is the first early season roadblock most people encounter.

Blossom-end rot occurs in tomatoes, peppers, zucchini, and other cucurbits. Early in the season as fruits develop quickly, they require a lot of calcium. Moisture plays a crucial role in calcium uptake in the plant. Though it may look like disease or insect injury, blossom-end rot is a physiological disorder caused by a lack of calcium transferring from the soil to developing fruits during dry weather.

Blossom End Rot

When a dry spell follows a time when plants get adequate moisture, calcium uptake into tomato plants is interrupted, causing the blossom-end of some fruits to develop a water-soaked, rotten appearance. Symptoms in peppers and cucurbits are similar in appearance, and occur for the same reason. Other factors that contribute to blossom-end rot include overly deep cultivation that damages plant roots and excessive applications of fertilizer containing ammonia and/or salts.

Growing vegetables in containers can be particularly tricky because containers tend to dry out quickly, leading to more extreme fluctuations in soil moisture than what plants experience in the ground. Be sure to water your container plants on a consistent schedule, and apply a fertilizer specifically formulated for tomatoes or vegetables that contains calcium as a micronutrient.

Blossom-end rot is typically an early season garden problem that balances itself out as summer progresses. Here are steps for minimizing blossom-end rot:

  • Maintain even soil moisture by adhering to a regular irrigation schedule. Consider mulching around plants to minimize moisture loss.
  • Avoid cultivating the soil too deeply and too close to the root systems of vegetable plants.
  • Use a fertilizer high in superphosphate and low in nitrogen. When adding nitrogen, use calcium nitrate rather than ammonia or urea forms.
  • Have your soil pH tested. Your vegetable garden should have a pH between 6.5 and 7. Visit our website for soil testing instructions.
  • As a last resort, use a foliar spray of calcium chloride. Be aware that calcium chloride can be phytotoxic if applied too frequently or in excessive amounts.

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

Welcome to Long Island Gardening

CCE Suffolk Community Horticulture is happy to launch this blog dedicated to the delights and concerns of gardeners on Long Island, New York. Our long growing season, sunny skies, temperate climate, and generally well-drained soils make this a wonderful place to grow plants. No wonder Suffolk County is New York’s top producer in terms of agriculture and horticulture sales. Some of the country’s bestselling nurseries and vineyards are located here, too.

Long Island also abounds with gardens of every sort—public, backyard, community, school, edible, ornamental, and wildlife habitats in many shapes and sizes—and this blog is designed for the gardeners who care for these spaces. Our goal is to serve your needs and interests by bringing you research-based information to improve your gardening experience on Long Island. CCE Suffolk Long Island Gardening is a forum where CCE Extension Educators, Horticulture Consultants, and Master Gardener Volunteers share their recent field experiences with you to help make Long Island a greener, healthier place to live.

Master Gardener Volunteers use drought-tolerant plants to beautify Medford Train Station.

Master Gardener Volunteers use drought-tolerant plants to beautify the Medford Train Station.

Here you’ll rediscover some of the most beloved features of the old Long Island Gardening Quarterly (formerly published by CCE Suffolk), including the question and answer format of its “Horticulture Inquiries” column. So please keep your questions coming! Email them to Robin Simmen, Community Horticulture Specialist, at rls63@cornell.edu or to anyone who posts on this blog about horticultural subjects of interest to you.

To receive the latest information as posts are added, subscribe to the blog by adding your email address above on the right side. A link to the blog is also nestled on the CCE Suffolk Gardening webpage for easy connection: http://ccesuffolk.org/gardening.

Happy gardening!

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