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
UMass Garden Calendar Photo Contest
Ever take a great garden photo and think “this would be perfect for the UMass Garden Calendar?” We are pleased to announce that we are now accepting photos submitted by the public. Submissions will be judged by the calendar team at UMass Extension and may earn a spot in the 2019 Garden Calendar. For more information visit the Garden Calendar page.
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.
Questions & Answers
Q: We are continually battling yellow nutsedge in the landscape on three properties we manage. We apply Snapshot 2.5TG in the spring and have successfully controlled weeds with the exception of yellow nutsedge. Yellow nutsedge is then spot treatment with RoundUp Pro during the season will minimal success. What other strategies can we try?
A: Snapshot is an excellent choice as a preemergence for weed control in landscape beds. It is labelled for use on a large number of landscape ornamentals and effectively controls annual broadleaf and grassy weeds. Snapshot will not control established perennial weeds such as yellow nutsedge. The herbicide dimethenamid will control yellow nutsedge when applied as a preemergent, in this case pre-sprout. Products that contain dimethenamid are Tower and Freehand from BASF. Tower is dimethenamid only and Freehand 1.75 G is a combination of dimethenamid and pendimethalin. Like Snapshot, Freehand is labelled for use on a large number of landscape ornamentals and effectively controls annual broadleaf and grassy weeds, however it is different in that it will control yellow nutsedge when applied as a preemergence application. Tower, a liquid formulation of dimethenamid, can be tank mixed will another preemergence product that is labelled for landscape to broaden the weed control spectrum. Yellow nutsedge escapes that are not controlled by Freehand, Tower or the Tower preemergence tankmix can be spot treated with a glyphosate-based product such as RoundUp. Spot treatments of glyphosate should be applied before yellow nutsedge reaches the 4-leaf growth stage. On a preventative note, if yellow nutsedge is on a few properties that you manage be mindful as not to spread yellow nutsedge to other properties that you manage.
Q: Our company treated a population of oriental bittersweet with RoundUp Pro. It turned yellow for a short time and then continued to grow. Is this the best control option?
A: The response you received is typical with postemergence applications of glyphosate for the control of oriental bittersweet. Products that contain triclopyr are a better postemergence choice. Glyphosate and triclopyr can be used as a cut stem/cut stump treatment. Selection of foliar versus cut stem/cut stump treatments will be determined by the growth habit of the oriental bittersweet. In other words, is it growing as a groundcover (low growing brush) or a tree-climbing vine. Oriental bittersweet is a prolific seed producer and seedlings/small plants are common. As part of an ongoing maintenance program these seedlings/small plant should be pulled by hand as they appear.
Randy Prostak, UMass Extension Weed Specialist
Trouble Maker of the Month
Hosta Virus X
Hosta Virus X (HVX) was first identified in 1996. Hosta enthusiasts have since been watchful for symptoms of the virus, which can include stunted, warped, or puckered leaves, color breaking or mottling (“inkbleed”), necrosis, and ring spots. These symptoms can be very subtle, and some plants will show no symptoms at all. Despite growers’ best efforts, plants infected with HVX are sometimes still propagated.
Most plant viruses have specialized relationships with the vectors that spread them. The most common type of vector is an insect pest such as aphids or thrips. HVX, however, has no known biological vector. The virus is spread mechanically, when sap from an infected plant is carried or splashed onto another plant. The virus needs a wound in order to infect, but this wound may be as tiny as a broken leaf hair. The virus is also spread by the propagation of infected daughter plants or infected seeds.
HVX does not kill plants; in fact, the color breaking symptom sometimes produced by the virus may even be considered desirable. A few hosta varieties were once propagated and admired for unique coloration that was eventually attributed to HVX.
There is no treatment for HVX once a plant is infected. Symptomatic plants should be dug up and destroyed. The virus can persist only in living tissue, so wait at least one season before replacing one hosta with another hosta to ensure any roots left in the soil have died. Be sure to clean gardening tools thoroughly between plants. If the problem is persistent, consider planting cultivars that are known to be resistant to HVX. ‘Bessingham Blue’, ‘Frosted Jade’, and Great Expectations’ are among several cultivars considered to be highly resistant to HVX.
Hostas can also get other viruses, such as impatiens necrotic spot virus (INSV), which is transmitted by thrips. Testing for HVX is available at the UMass Extension Plant Diagnostic Lab. For information on sample submission, please see http://ag.umass.edu/services/plant-diagnostics-laboratory
Angie Madeiras ,UMass Extension Plant Pathologist
Plant of the Month
Echinacea purpurea, purple coneflower
Echinacea purpurea, commonly known as purple coneflower, is a long flowering perennial native to eastern North America and hardy to USDA hardiness zones 4-9. It is a medium sized herbaceous perennial with upright clump growth habit growing 2-3 feet tall and 18-24 inches wide. In optimal conditions they can grow up to 5 feet with a 2 feet spread. Purple coneflower prefers a well-drained soil in full sun or partial shade. Plants are tolerant to heat and drought once established. The leaves of Echinacea purpurea are medium to dark green, and are originating as clump from the crown (basal leaves) or alternating along the flowering stems (upper leaves). Leaves tend to wilt under drought conditions but recover with the evening dew and reduced transpiration. Echinacea offers a distinctive array of daisy like flowers in many colors including purple, pink, white, orange, yellow, and green. The best floral performance occurs when Echinacea is planted in sites with morning sun followed by afternoon shade. Echinacea blooms from June to August with re-blooming occurring in late summer and early fall. Deadheading encourages re-bloom and improves general appearance. Flowers are attractive to butterflies and bees. They are suitable for mass plantings, as a perennial border or in entryways. They are also good for cut flowers.
Echinacea purpurea are easy to grow and are not heavy feeders. Avoid heavy fertilization which leads to tall, leggy plants that fall over. Plants can be propagated by clump division, root cuttings from peripheral roots or by seeds. Divide clumps about every 4 years when they become crowded. Echinacea can self-seed, especially if some of the seed heads are left in place. This can slowly become a problem in perennial beds.
Leaf scorch is the most common problem and often occurs during drought periods. Other problems of Echinacea include aster yellows diseases, leaf spot disease and Japanese beetle.
Some of the popular varieties include:
- Echinacea ‘Crimson Star’- deeply pigmented crimson-lavender petals with reddish central disks
- Echinacea ‘Magnus’ – rosy purple flowers
- Echinacea ‘White Swan’ - White petals with golden-green central disks.
- Echinacea ‘Firebird’ – Red-orange flowers, long lasting flower color
- Echinacea ‘Glowing Dream’ – Deep watermelon pink flowers, purple stems. Flowers glow.
- Echinacea ‘Balsomador’ – Bright deep orange flowers
- Echinacea ‘Millkshake’ – Double creamy white flowers
Geoffrey Njue, UMass Extension Floriculture Program
Upcoming Events
Featured Event: Bark Beetle Identification Trainings
This three-day training will bring together Scolytinae taxonomy experts from federal agencies and universities to provide a small group of participants with hands-on, one-on-one training on how to identify specimens to genus and species in this difficult subfamily of insects. Special topics related to bark beetles will be discussed, including but not limited to detection, monitoring, and prediction systems for the bark beetles and information about their complex fungal associates.
Event Location: Fernald Hall, UMass Amherst
Other Upcoming Events:
- 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
- 10/4: Fall Intrest Tree and Shrub ID Walk
- 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.
