A monthly e-newsletter from UMass Extension for landscapers, arborists, and other Green Industry professionals.
To read individual sections of the message, click on the section headings below to expand the content:
Hot Topics
New Insect Identification Online Resources Fact Sheet
Looking for resources to help identify an insect? Check out the new UMass Extension Insect Identification Online Resources Fact Sheet. Keep in mind that identifying an insect via only a photograph can be very difficult if not impossible and that misidentifications are possible. If you have a pest insect on an ornamental tree or shrub that you cannont identify, consider sending it to the UMass Plant Diagnostics Laboratory for identification.
Ticks are active at this time!
Remember to take precautions when working outdoors and to conduct daily tick checks. The UMass Amherst Laboratory of Medical Zoology tests ticks for Lyme Disease and other tick-borne pathogens. Visit the Tick Report website for more information.
UMass Garden Calendar Photo Contest
UMass Extension will be having a photo contest for the 2019 Edition of the Garden Calendar. Have your camera handy and keep an eye out this summer for contest-worthy pics! Submission details will be coming in a later issue of Hort Notes.
Questions & Answers
Q: I have an eastern white pine with browning needles, premature needle shedding and branch dieback. What fungicide should I use for treatment?
A: Fungicides should not be the first choice for treatment when the cause of decline is not yet determined. Symptoms of decline, such as the type exhibited by many landscape and forest white pines at this time, can be the result of many different stresses. As is often the case, symptoms resulting from abiotic stress (e.g. drought, winter injury, root compaction/severing and air pollution) can resemble those caused by an insect pest or pathogen. Currently, a great deal remains unknown about what specific factors are driving white pine decline. White pine needle blight (WPNB) has been linked to the demise of many trees and can result from infection by one or several fungal pathogens. Yet, treatment is not easily implemented with fungicides alone. White pines that are sheared for thickness, planted in shaded settings or established in tight rows for screening are usually more prone to WPNB. Additional cultural factors should be considered first before pests and pathogens, such as deep planting, poor-quality soils, excessively drained soils, lack of irrigation during establishment, waterlogged soils, small rooting zone, among others. Another factor is the likelihood of successful fungicide coverage, should WPNB be the primary issue. Large white pines can have very high levels of inoculum (needles harboring needle blight pathogens) present in the canopy. Unless the application can thoroughly reach a majority of infected tissue, and be applied at the optimal time, it may be more prudent to allocate resources to other trees on the property. This spring has been very wet with several significant rainstorms. This has created ideal conditions for the spread of WPNB pathogens. Even with successful treatment, the disease may persist and intensify.
Q: Can I do anything at this time to control anthracnose?
A: The wet spring in 2017 helped to initiate widespread outbreaks of anthracnose on maple, dogwood, oak, crabapple, beech, sycamore, among many other deciduous hardwoods. Anthracnose diseases vary from minor (scattered leaf spots and blotches) to serious (complete blight of infected foliage and shoots in large portions of the canopy). In some cases, perennial cankers can develop on stems and small branches. Anthracnose outbreaks are rarely fatal for trees and shrubs but when the diseases occurs in combination with other stresses, such as insect defoliation or drought stress from very dry year, its effects can be amplified. Growth and spore production by anthracnose fungi typically decreases significantly during July and August, when conditions are typically hot and dry. Yet, once cooler and wetter weather returns in autumn, these pathogens can become more active once again. While foliage is senescing at this time, a buildup of inoculum in autumn can result in higher disease pressure the following spring. Removal of discarded foliage is important to reduce inoculum at the site. Treatment with fungicides in spring of 2018 may be warranted for high-value trees and shrubs. It’s important to treat early, as the most damaging anthracnose outbreaks take place when new leaves are expanding and are not yet fully developed. For trees infected by anthracnose fungi this year, establish management plans for next year to avoid another bad year.
Nicholas J. Brazee ,UMass Extension Plant Pathologist
Trouble Maker of the Month
Ticks
A note about Tick Awareness: deer ticks/the blacklegged tick (Ixodes scapularis), the American dog tick (Dermacentor variabilis), the brown dog tick (Rhipicephalus sanguineus) and the lone star tick (Amblyomma americanum) are all found throughout Massachusetts. Each can carry their own complement of diseases. Anyone working in tick habitats (particularly, wood-line areas, forested areas, and landscaped areas with ground cover) should check themselves regularly for ticks while practicing preventative measures. If you find a tick attached and/or engorged (swollen and full/partially full of blood) from feeding on you, visit the web page of the UMass Laboratory of Medical Zoology and click on the red Test a Tick button for more information. The UMass Laboratory of Medical Zoology is capable of testing the tick for the presence/absence of many tick-borne diseases and can provide you with invaluable information to provide to your medical doctor.
For information about managing ticks in landscapes, among other topics, please visit the Tick Management Handbook from the Connecticut Agricultural Experiment Station.
Ways to Reduce Exposure to Ticks:
- Avoid tick habitats: when possible, take care when spending time in wooded, brushy, or grassy areas. This is not to say that these environments are to be avoided entirely, however know that in these locations, your risk of encountering a tick increases. When in these areas, take the following steps to reduce tick-associated risks:
- Use insect repellent: products containing the active ingredient DEET (N,N-Diethyl-m-toluamide) may be applied directly to the skin; products containing a pyrethroid, such as permethrin, may be used on clothing. Follow all label instructions for any product used! A URI study found that individuals wearing permethrin-treated sneakers and socks were 73.6 times less likely to be bitten by a tick than those wearing untreated footwear. For more information, please visit: http://www.tickencounter.org/prevention/permethrin
- Wear protective clothing: when possible, wear long-sleeved shirts and pants when in tick habitats. Tuck pants into socks and wear light-colored clothing to make it easier to spot any ticks trying to hitch a ride.
- Shower after outdoor activities: use this as an opportunity to do a thorough tick-check all over the body and in your hair. Check everywhere. Ticks have no reservations about violating privacy.
- Put clothes in the dryer: particularly after spending time in tick-favored habitats, place all clothing within the dryer. Ticks are prone to desiccation (drying out) and this will kill any attached to the clothing. The CDC (Centers for Disease Control and Prevention) suggest tumble dry on high heat for 10 minutes to kill ticks on clothing. If the clothing is damp, additional time may be required. If the clothing needs to be washed prior to drying, use hot water. If this is not possible, tumble dry on low heat for 90 minutes or high heat for 60 minutes or until clothes are completely dry and warm following a wash. For more information, visit: https://www.cdc.gov/ticks/avoid/on_people.html
- For additional detail about these steps, please visit: http://www.tickencounter.org/prevention/protect_yourself
How to Properly Remove an Attached Tick:
- Use pointed tweezers: disinfect the tweezers with rubbing alcohol as well as the area the tick is attached to.
- Grasp the tick as close to your skin as possible: place the tweezers on the tick as close to the skin where it is attached as possible.
- Pull the tick straight out, firmly: the mouthparts of the tick are perfect for gripping tightly to (and in) the skin. Therefore, they are often difficult to remove. Grasping the tick tightly, close to the skin, and pulling slowly upward with the tweezers will achieve the best results.
- Disinfect the skin: once the tick has been removed, disinfect the area again with rubbing alcohol.
- Consider visiting your physician: consider visiting your physician following a tick bite, particularly if you develop a rash, fever/chills, or aches and pains. Do not rely on a rash alone to make the determination to visit your doctor. With Lyme disease, for example, the rash (known as erythema migrans or EM) associated with this disease only occurs in 70-80% of persons infected with Lyme disease and may take 3-30 days to develop. Other tick-borne diseases can cause different rashes/symptoms.
Please visit the following web page for step-by-step tick removal instructions, including an animated video: http://www.tickencounter.org/prevention/tick_removal
*Please note that when a tick is embedded, only the mouthpart (hypostome) is pushed into your skin. Therefore, the “head” of the tick is not ever left behind in the area where the tick was attached. There is no need to “dig out” skin around the area where the tick was attached. Refer to the above video for more information.
How NOT to Remove a Tick:
- “Painting” the tick: some myths about coating attached ticks with petroleum jelly or nail polish still exist. DO NOT do this. The goal is to remove the tick as quickly as possible. Increased time attached to your body means an increased chance that the tick could transmit a disease. Note: depending upon the disease, the amount of time needed for transmission varies.
- Burning the tick: some myths about burning the tick with a match or other object still exist. DO NOT do this. Remove the tick with pointed tweezers. (See above instructions.)
- Freezing the tick: some myths about freezing an attached tick still exist. DO NOT do this. Again, your goal is to remove the tick as quickly as possible. (See above instructions.)
Further Tick-Related Resources:
Cape Cod Cooperative Extension
Centers for Disease Control and Prevention
Lyme Disease Association, Inc. (Non-Profit)
Massachusetts Department of Energy and Environmental Affairs
Massachusetts Department of Health and Human Services
Tick Management Handbook, CT Agricultural Experiment Station
UMass Amherst Laboratory of Medical Zoology, Tick Testing
University of Rhode Island TickEncounter Resource Center
Tawny Simisky, UMass Extension Entomologist
Plant of the Month
Aesclepias tuberosa, butterfly weed
Asclepius tuberosa is a member of the Apocynaceae, or milkweed family and is an ideal plant for pollinators. The foliage provides food for larval stage of the Monarch butterfly (Danaus plexippus), Queen Butterfly (Danaus gilippus) and the Milkweed Tussock Moth (Euchaetes egle), and the flowers provide a nectar source for adult butterflies as well as many bees, wasps, ants, hummingbirds and beetles. Butterfly weed is hardy to zones 4-9 and reaches 2-3’ high with about a 2’ spread. It has been named Perennial Plant of the Year for 2017 by The Perennial Plant Association.
A. tuberosa is drought tolerant and deer resistant and has long-lasting orange or yellow flowers that appear throughout the summer. The flowers can be used as cut flowers and unlike other milkweeds, it produces little sap. The flowers are flat-topped clusters of upright orange flowers. Each flower has 5 colorful petals that hang down, and 5 upright curved petals called hoods, each possessing one horn forming within the hood. When cross-pollinated, a dry fruit forms, (called a follicle), and splits open along one side to disperse the seeds.
A. tuberosa occurs naturally throughout most of the eastern two-thirds of North America in prairies, open woods and hillsides. They grow best in full sun in well-drained soil and once established, plants can tolerate drought, which makes them a good choice for dry, sunny slopes and full-sun gardens. Young plants develop from a single central stem but as plants mature, they develop shoots at the base and produce multiple erect stems from a large taproot. Due to the taproot, division can be difficult, however if attempted, it is best done in early spring before new growth begins.
Butterfly weed is most often grown from seed and can also be propagated by root cuttings. Seed cultivars such as 'Gay Butterflies' may contain bright yellow and red individuals, but the common orange color predominates. Another cultivar to consider is ‘Hello Yellow’ which produces bright yellow flower clusters.
Plants are often slow to emerge from dormancy in spring. Plants can be pruned back in spring. Deadheading flowers during the summer will prevent reseeding, keep the plants more attractive and promote a second flush of color about a month later.
A. tuberosa is prone to aphid infestations. Avoid using neonicotinoids pesticides on A. tuberosa plants in landscapes to prevent killing feeding butterfly larvae and other pollinators. Neonicotinoid pesticides vary in their toxicity to specific insects. Some neonicotinoids are more toxic to butterfly larvae and others are more toxic to bees.
A strong spray of water can be effective to dislodge aphids from plants. Also, insecticidal soap can be used to spot-treat dense aphid infestations. Soaps kill on contact and do not have residual activity. If aphids become a persistent pest problem each year, consider including nearby plantings of habitat plants such as alyssum (Lobularia maritima ‘Snow Princess’) to attract natural enemies that will feed on aphids. Habitat plants are pollen producing, flowering plants that are highly attractive to natural enemies and many pest species. They provide food (pollen, nectar or pests) and shelter for natural enemies, and a place for them to lay eggs. Alyssum, fennel, dill and marigolds are examples of habitat plants that effectively attract hover flies. The hoverfly larvae feed on aphids and other soft-bodied insects.
Note that all parts of A. tuberosa are poisonous if ingested.
References
Shinn M. 2017. Perennial Plant of the Year: Asclepias tuberosa, Horticulture
http://www.hortmag.com/plants/perennial-plant-of-the-year-2017-asclepias-tuberosa
2017 Perennial Plant of the Year. Perennial Plant Association
http://www.perennialplant.org/index.php/component/k2/item/190-2017-perennial-plant-of-the-year
Asclepius tuberosa. North Carolina State University Extension
https://plants.ces.ncsu.edu/plants/all/asclepias-tuberosa/
Tina Smith, UMass Extension Floriculture Program
Upcoming Events
Featured Event: UMass Turf Research Field Day
UMass Turf Research Field Day is presented on a bi-annual basis to highlight the wide range of research projects currently taking place at the UMass Joseph Troll Turf Research Center in South Deerfield, MA as well as on research being conducted at other locations by University of Massachusetts Turf Program faculty, staff, and graduate students. Current UMass research includes studies on the biology and integrated management of turf-damaging diseases and insects, short- and long-term weed management, pesticide exposure, fertility, drought management, as well as a range of National Turfgrass Evaluation Program fine turf trials.
Event Location: UMass Joseph Troll Turf Research Center
Other Upcoming Events:
- 7/26: UMass Turf Research Field Day
- 8/8: Bark Beetle Identification and Related Topics Trainings Day 1
- 8/9: Bark Beetle Identification and Related Topics Trainings Day 2
- 8/10: Bark Beetle Identification and Related Topics Trainings Day 3
- 9/23: Landscape and Forest Tree and Shrub Disease Workshop
- 11/29-12/1: New England Grows
For more information and registration for any of these events visit the UMass Extension Landscape, Nursery, and Urban Forestry Program Upcoming Events Page.
Additional Resources
For detailed reports on growing conditions and pest activity – Check out the Landscape Message
For commercial growers of greenhouse crops and flowers - Check out the New England Greenhouse Update website
For professional turf managers - Check out Turf Management Updates
For home gardeners and garden retailers - Check out home lawn and garden resources. UMass Extension also has a Twitter feed that provides timely, daily gardening tips, sunrise and sunset times to home gardeners, see https://twitter.com/UMassGardenClip
Diagnostic Services
A UMass Laboratory Diagnoses Landscape and Turf Problems - The UMass Extension Plant Diagnostic Lab is available to serve commercial landscape contractors, turf managers, arborists, nurseries and other green industry professionals. It provides woody plant and turf disease analysis, woody plant and turf insect identification, turfgrass identification, weed identification, and offers a report of pest management strategies that are research based, economically sound and environmentally appropriate for the situation. Accurate diagnosis for a turf or landscape problem can often eliminate or reduce the need for pesticide use. For sampling procedures, detailed submission instructions and a list of fees, see Plant Diagnostics Laboratory
Soil and Plant Nutrient Testing - The University of Massachusetts Soil and Plant Nutrient Testing Laboratory is located on the campus of The University of Massachusetts at Amherst. Testing services are available to all. The function of the Soil and Plant Nutrient Testing Laboratory is to provide test results and recommendations that lead to the wise and economical use of soils and soil amendments. For complete information, visit the UMass Soil and Plant Nutrient Testing Laboratory web site. Alternatively, call the lab at (413) 545-2311.
