Hort Notes 2024 Vol. 35:2

A monthly e-newsletter from UMass Extension for landscapers, arborists, and other Green Industry professionals, including monthly tips for home gardeners.

Click on the headings below to jump to that section of the newsletter.

Last Call for Photos for the 2025 UMass Garden Calendar

Last chance! We'll be choosing the photos in early May and are still accepting photos from the public for possible use in the 2025 Garden Calendar.

Photos must be horizontally oriented with high resolution and feature garden plants of particular horticultural interest. Winning photographers will be credited in the Garden Calendar and will receive 5 free calendars. For complete info and submission instructions, go to ag.umass.edu/gardenphotos

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Additions to Massachusetts Prohibited Plant List Public Hearing

The Massacusetts Department of Agricultural Resources (MDAR) will be holding a hearing regarding the addition of the following plants to the MA Prohibited Plant List on Friday, April 26, 2024 from 10:00 to 11:00 am:

• Japanese black pine (Pinus thunbergii)
• Callery/Bradford pear (Pyrus calleryana)               

Find the Zoom link and details in MDAR's Hearing Notice.

Testimony may be presented orally at the virtual hearing or in writing. Written comments will be accepted until 5:00 pm on April 26, 2024. Written testimony must be submitted by e-mail to taryn.lascola@mass.gov or by mail to Massachusetts Department of Agricultural Resources, 225 Turnpike Road, Southborough MA 01772 Attn: Taryn LaScola.

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The Birds and Bees (and Ticks)

A red-winged blackbird calls just outside my window. The unequal cellophane bees (Colletes inaequalis) have yet to emerge from their slumber in my yard, but I know they’ll be here shortly.

Spring also heralds the emergence of nymphal deer ticks (Ixodes scapularis). They have been diapausing since their time as larvae up to 10 months ago. Nymphal deer ticks are most active from mid-April through the end of June. If you aren’t already using permethrin, EPA-registered repellents, and conducting daily tick checks, now is a great time to start.

The adult deer ticks that we have contended with since last fall are still around, but their time is running out. Once we hit summer, they will have either successfully fed and laid eggs. Or they will perish, alone and unloved (or, possibly, alone and loved, since mating can occur before or after finding a host).

Speaking of birds and bees, deer tick reproduction is rife with mysteries and misunderstandings. Contrary to popular belief, ticks do not lay eggs in nests. There is nothing constructed to house the eggs and protect them. After feeding to repletion, adult females simply drop off their hosts. Once on the ground, female ticks will attempt to hide under leaf litter. Like many other native organisms, ticks also enjoy the protection that “leaving the leaves” provides for them throughout winter. Other than moving deeper towards the soil surface, they may not move more than a few centimeters from the spot where they fell. Once situated, each female will lay all her eggs at that location.

What happens if you happen upon one of these egg masses? In the unlikely event that you do, I can reassure you that it isn’t something you need to “burn with fire” as the internet erroneously urges you to do. Simply, place the eggs in another location. This can be a safe spot in the woods under leaves, where the ticks can remain protected until they hatch. Or, place them in a cup of soapy water, which will ultimately kill them. Do whichever suits your philosophy. Regardless of which approach you take, the eggs may experience a high degree of mortality depending on their location. Like other life stages, egg masses are highly sensitive to local environmental conditions, such as humidity.

Hatching is also not immediate. Regardless of whether the eggs were laid last fall or 4 weeks ago, they will not hatch until the time is right. This is generally around July. This means egg mass can be safely handled throughout spring without fear. In addition, larvae – the first life stage – never hatch carrying the germs that cause Lyme disease, babesiosis, or anaplasmosis. They rarely bite humans, preferring instead to feed on birds and small mammals.

Blake Dinius, Plymouth County (MA) Entomologist

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Trouble Maker of the Month

Exobasidium Gall of Rhododendron and Azalea

Exobasidium gall is a very common disease that occurs wherever rhododendron and azalea are grown in ornamental settings. Infection by Exobasidium results in hypertrophic enlargement of leaves, flowering parts and sometimes woody stems (Sinclair and Lyon 2005). The galls vary in size and color, depending on the host and specific plant part that is infected. Typically, the galls first appear pale green to cream-colored, becoming reddish-brown over time. The galls are small to large, highly conspicuous, and easily diagnosed through visual assessment. Tufted growth (witches’ brooming) can also develop as a result of infection. 

It’s believed that the fungus establishes from spores that overwinter in bud scales (Walker and Benson 2014). These spores then germinate and grow into the stomata on the underside of newly developing leaves or penetrate directly into developing leaves, flowering parts, and succulent shoots (Sinclair and Lyon 2005). Exobasidium then grows intercellularly (between cells) within the host, parasitizing tissues and inducing hypertrophic growth that creates the distinctive swellings and galls. Most galls are annual, meaning they are produced only once from the infected plant part. They develop in late spring (late April to May) during periods of mild and wet weather. As the galls mature in early summer (mid-June to early July), they become covered in a mass of white-colored spores. 

Exobasidium gall is caused by several species of the fungal pathogen Exobasidium. While the taxonomy and host range of many species continues to change, it appears that E. vaccinii is one of the most common species in the United States (Walker and Benson 2014). An assortment of native and non-native Exobasidium species likely occurs in New England, due to widespread distribution through the nursery trade. Numerous species and cultivars of rhododendron and azalea (Rhododendron) are susceptible to infection. Exobasidium species also attack blueberry (Vaccinium) and camellia (Camellia), among other plants in the Ericaceae.

Overall, Exobasidium gall is not considered a serious threat to the health of infected rhododendrons and azaleas (Walker and Benson 2014). However, the disease can result in reduced flowering and decreased aesthetic value of infected plants. Pruning or hand-picking of the galls as they appear is often recommended for disease control. However, the effectiveness of pruning out the immature galls when they first appear in the spring is unproven. Because most galls are annual, they cannot be produced again from the same tissue. Yet, removing the galls before they mature and produce a coating of white-colored spores in early summer should reduce localized inoculum. In landscapes where the disease is a problem, increasing sunlight and exposure can sometimes help to reduce disease severity. Avoid overhead watering, especially during the spring months when new growth is developing, as free moisture stimulates disease development. Fungicides are likely to have little utility against the disease. Mancozeb is one of the few fungicides labeled for use against Exobasidium, but its use is often only necessary in nursery and greenhouse settings where humidity is persistently high. Avoid the use of chlorothalonil, as it can be harmful to beneficial pollinators. Avoid any fungicide application before and during periods of flowering in the spring. 

Additional photos of Exobasidium gall can be found here.

Nicholas J. Brazee, UMass Extension Plant Pathologist

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Q&A

Q. I operate a lawn care company in eastern Massachusetts. Most, if not all, of our accounts get a preemergence herbicide for crabgrass control. When is the best time to apply these preemergence materials?

A. We commonly use the deciduous shrub forsythia, Forsythia intermedia, as a phenological indicator for the application of these preemergence annual grass herbicides. Application should be applied when forsythia is in full bloom in your area, with the last application occurring as the first few flowers hit the ground (typically late April to very, very early May). Sometimes earlier than normal warm weather in the spring might tempt us to get the season rolling, but it is important to understand that these herbicides only have herbicidal properties for a certain period of time. Temperature and moisture of the soil, along with soil characteristics, impact the life span of these herbicides. When thinking, “we need to get out there and get our preemergence herbicides down”, pause a few seconds and remember “Early down, early gone.” An herbicide applied in early to mid-March that typically provides 5 to 7 weeks of control will likely be ineffective at controlling crabgrass in May and June when you need the product to do its work. Additionally, 330 CMR 31.00: An Act Relative to the Regulation of Plant Nutrients regulates nutrient applications in the Commonwealth of Massachusetts. With regards to turf, this regulation states that “no applications of plant nutrients shall be made to drought dormant, cold dormant, inactive or otherwise brown turf." This prohibits the application of a preemergence annual grass herbicide in an on-fertilizer formulation that is applied in early spring to dormant turf. Lastly, realize that even a properly timed preemergence annual grass herbicide may not provide 100 percent control and that sometimes there is a need to tackle annual grassy weeds with a postemergence herbicide.

Q. I have seen lesser celandine in turf on a property that I manage. Last year, I noticed it starting to show up at a couple of other properties. What is the best way to control this weed?

A. Lesser celandine, also called fig buttercup, fig-crowfoot, or dusky maiden, (Ficaria verna or Ranunculus ficaria), is an herbaceous invasive perennial plant found throughout New England. This species is a spring ephemeral, with shiny, dark green, kidney-shaped leaves and bright-yellow, glossy, flowers with 8 to 12 petals. As a spring ephemeral, it is only apparent in the spring and then goes dormant for the rest of the year. Lesser celandine reproduces by bulblets, tuberous roots, and seeds. As a spring ephemeral, it often difficult to determine if an herbicide worked or if the symptoms you see are just the species becoming dormant later in the spring or early summer. Herbicides known to effectively control lesser celandine in turf are triclopyr and dicamba. Products that contain both herbicides are the best choice. You mention it has shown up on other properties that you manage; this might suggest that you are or someone else could be inadvertantly spreading it from one location to another via mowers, aerators, or other lawn maintenance equipment. For early occurrences of this weed in new locations, consider digging plants up and disposing of them in a manner that will prevent their further spread.

Q. I see a plant in some turf areas that are mostly void of desirable turfgrasses. There seems to be more of this weed in areas the receive a fair amount of wear and tear. The plants are in clumps and the leaves are somewhat wiry and dark green. Does this sound like path rush? And if so, what is the best way to control it?

A. From the great description of growth habit and leaves, I think this very well could be path rush, Junus tenuis. Please visit https://extension.umass.edu/weed-herbarium/weeds/juncus-tenuis to confirm identification. Path rush, as the name suggests, is more likely to grow in areas with compacted soil. Core aeration will not control this weed but alleviating soil compaction and establishing of healthy stand of turf will decrease the likelihood of it returning. Pyrimisulfan, a new herbicide in 2021, has been shown to be active on path rush. First coming to the market as Vexis^TM in 2021 as a granular, this season pyrimisulfan will be available under the tradename Arkon^TM. Arkon^TM is a 0.103 lb per gallon formulation of pyrimisulfan. This liquid formulation will allow for spray applications for the control of path rush. Applications provide the best control when path rush is activity growing. Sequential applications are permitted after 30 days.

Randy Prostak, UMass Extension Weed Specialist

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Garden Clippings Tips of the Month

April is the month to . . . .

• Start tomato, pepper, and eggplant transplants indoors. Mix up the usual varieties by trying an All-America Selection. All-America Selections are vegetables and flowers chosen for their exceptional performance in test gardens nationwide. Recent winners include tomato ‘Purple Zebra’ (2022), pepper ‘Red Impact’ (2024), jalapeno pepper ‘San Joaquin’ (2023), and eggplant ‘Icicle’ (2022). 

• Plant potatoes. Use certified seed potatoes for reliable growth and disease resistance. Cut potatoes into pieces, with each piece containing at least one eye, and allow the pieces to air dry for a few days before planting. Grow potatoes in the ground, a raised bed, or a container (grow bag, large bucket with drainage holes, etc), ideally one that is no more than 2 to 3 feet tall with a 10- to 15-gallon capacity. Add 6 to 8 inches of potting soil to the bottom of the container before placing potato pieces and covering them with 3-4 inches of soil. As potatoes grow, “hill” them periodically by mounding soil (or straw) around the stems, up to an inch below the lower leaves. This is done first when plants are 6 to 8 inches tall, and then every 2 to 3 weeks until harvest. Hilling shields developing potatoes from sun exposure, which can turn them green (making them bitter and even toxic if consumed in excess, due to production of the compound solanine).

• Harden off indoor-started cool season vegetable seedlings before transplanting into the garden. Although broccoli, lettuce, onions, and other cool season plants can tolerate cool temperatures and light frosts, they still need to be acclimated to the outdoors. Do this by placing seedlings in a cold frame for 7 to 10 days prior to transplanting. Alternatively, set seedlings outdoors in a partially shaded location protected from wind—start with an hour exposure and gradually increase their time outside by a few hours each day for the 7- to 10- day period.

• Get a soil test! May and June are the busiest time of year for the UMass Soil & Plant Nutrient Testing Lab, so beat the rush by submitting soil samples before mid-May. The Routine Soil Analysis tests for pH, major and micro nutrients, lead, and cation exchange capacity and provides crop-specific lime and nutrient recommendations. For the order form and info on how to take and send a sample, go to soiltest.umass.edu.

• Refresh landscape mulches. Mulches conserve water, moderate soil temperature, help prevent soil compaction, and inhibit weed growth. Create grass-free zones around trees planted in lawn areas and mulch with wood chips, bark, or pine needles. 

• Monitor the garden for pests. Look for lily leaf beetle, a ¼-inch long, black-legged, bright red insect feeding on leaves of true lily species, fritillaria, and occasionally lily-of-the-valley, Solomon’s seal, hollyhocks, and hosta. Check boxwoods for leaf miner larvae. Small bumps on the undersides of leaves are evidence of the larvae inside; the tiny green or orangey-yellow worm-like larvae are visible when affected leaves are peeled apart. Watch for cool season spider mite activity on broadleaf evergreens (e.g. andromeda, azalea, Japanese holly) and conifers (e.g. spruce, arborvitae, juniper, hemlock, pine). Damage appears as stippling on leaves or needles, and magnification is required to see mite eggs—add a hand lens to the garden pest toolkit.

• Watch for deer ticks while working outdoors.  Adults are active and can transmit a range of diseases if they become attached to and feed on unsuspecting gardeners. Take preventative measures when working or playing outdoors to reduce the chance of ticks attaching, e.g., frequent tick checks; wearing light-colored, protective clothing; and treating clothes with permethrin (following label instructions). 

• Plan and plant a cut flower garden. Hardened off snapdragon and calendula transplants can be planted out about a month before last average frost date, ageratum and sweet peas can be planted out two weeks prior to last frost date, and zinnias, cosmos, and sunflowers should wait for planting out until a few weeks after the last frost date. 

• Prune roses. At a minimum, cut back to the base all canes that are dead, damaged, or thin and weak looking. Prune late summer- and fall-blooming shrubs, such as butterfly bush, summersweet, panicle hydrangea, sweetspire, and potentilla, if not done last month. 

• Refrain from mowing lawngrass until it is a little more than 3 inches tall, then mow back to a height of no lower than 2½ to 3 inches. Mowing high encourages deeper rooting and helps prevent weed problems, since taller grass shades the soil and keeps it cool - conditions which hinder crabgrass seed germination.

• Fertilize houseplants. They are beginning to put on new growth as they receive more sunlight, more natural humidity, and increased warmth. However, be wary of over-fertilizing, signs of which may include browning leaf tips, yellowing and wilting lower leaves, leaf drop, and a salty-looking “crust” of fertilizer on the soil surface. Flush out excess fertilizer by watering plants thoroughly with clear tap water.

• Celebrate Earth Day by committing (or continuing) to use Earth-friendly gardening practices, e.g. composting, conserving water, selecting appropriate plants for site conditions, improving soil with organic matter and no-till gardening, managing weeds and pests responsibly, and supporting pollinators and other wildlife with diverse plantings.

Jennifer Kujawski, Horticulturist

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The Benefits of Using Conifers in the Urban Landscape - Part II

The basis for proper function is proper design. When designing an infrastructure system for a municipality, engineers and planners must take many different criteria into consideration to ensure that the system functions correctly and accomplishes the given objectives for that site or region. These criteria may include efficiency, costs and returns, current or future conflicts, and components available for use. The urban forest, as a part of the infrastructure system of a municipality, is no different. Just as when civil engineers take on the task of building a road network, urban foresters should strive to create an urban forest network that works as efficiently as possible, avoids major conflicts, and provides a high return.

In our introductory article in the previous issue, we discussed some of the benefits associated with the use of evergreen conifers in urban plantings. These benefits include helping to increase the tree species diversity of the urban forest, increasing annual rainwater interception and annual pollution absorption, and the promotion of urban wildlife diversity. Here, we will discuss important considerations to ensure that conifers add optimal value to the urban forest. It is important to use these different infrastructure components in the appropriate places; it is important to properly design the urban forest to ensure its optimal functionality. 

Due to seasonal changes and tree functional type (e.g. evergreen conifer, broadleaf deciduous, broadleaf evergreen), some trees provide services during certain times of the year, while providing less of those services – or even disservices – at other times. For instance, an evergreen tree provides summertime shading, which is generally regarded as a positive attribute, but also wintertime shading, which may be a negative attribute. A deciduous tree, however, provides this same summer shading benefit, but does not maintain a thermal buffer or privacy barrier during the wintertime, which can be a negative attribute. Wintertime shading is a notably important aspect to consider when planting evergreen conifers in the urban landscape in New England, and most notably when planting them as street trees. Ice buildup on roads can cause significant issues, so it is necessary to allow for optimal winter sun exposure on streets. In New England, the sun typically strikes on the southern exposure and casts shadows to the north. Thus, planting evergreen trees on the south side of an east-west oriented street will cause a shadow to be cast over the street during the winter. This conflict may be avoided, however, by planting evergreen species on the north side of the street and deciduous species on the south side.

By employing this technique, one can obtain greater tree species diversity and the same year-round ecosystem services that were discussed in part I, while still gaining beneficial winter sun exposure. Furthermore, shade-tolerant evergreen conifers may be established within the vicinity of a permanent object (i.e. building) that is already casting shade. Because the road is already shaded, the evergreen conifer does not cast further shading, but does contribute positive ecosystem services. By taking sun exposure and aspect into account, conifers can be included as street trees without causing conflicts by way of disservices during winter. In addition to proper placement along streets and travelled areas, installations of evergreen conifers may be designed to function as living screens.

Due to their dense, persistent foliage, many evergreen conifers can efficiently block sight, sound, and wind. By using evergreen conifers as thermal buffers and wind blocks around a building, the building’s efficiency can be increased by up to 25% by limiting the amount of heat loss due to cold air infiltration, or by the cooling of the building shell via passing wind. Used as audio or visual barriers, evergreen conifers can also help to muffle unwanted road noise from highways and block unsightly views. Salt-tolerant species of conifers can also act as buffers between roads and nearby areas that may be sensitive to road salts. By planting evergreen conifers around freeways, the noise, sight, and salt pollution can be better contained to those areas. Evergreen conifers can also absorb pollution and particulate matter that is emitted from highway traffic and block water spray continuously throughout the year. Though the buffering benefits from evergreen conifers are obvious, they may also be planted as part of a strategy to help decrease the urban heat island effect often associated with urban settings.

It has been shown that outdoor spaces with high leaf area indices (LAI) have lower soil, surface, and ambient air temperatures. LAI is a measure of how dense a tree canopy is, or how much leaf cover is present over a given unit of area. The higher the LAI, the denser the tree cover. Studies have found that areas with high LAI have cooler soil and surface temperatures by 7°C (12.6° F) and 6°C (10.8° F), respectively. Many conifers maintain dense crowns year-round with high LAI. Planting evergreen conifers therefore helps to keep small outdoor spaces, or microclimates, cool. By cooling enough of these microclimates throughout the urban environment, the macroclimate may also be influenced positively where the effects of the urban heat island may begin to be addressed.  

According to inventory data from across the United States, conifers appear to be notoriously underrepresented as urban trees. Of the trees inventoried in Portland, Oregon (just under 40,000), only 2.2% were determined to be evergreen conifers. Chicago, Illinois featured only about 9.1% coniferous street trees, while Boston, Massachusetts had notably no conifers listed in their top 25 species that comprised 96.7% of their street trees. Minneapolis, Minnesota featured only 0.3% conifers, Charlotte, North Carolina 8.5%, and Berkeley, California only 4% of their community tree inventories, respectively. These numbers equate to the simple fact that cities are not taking full advantage of the benefits that may be derived from increasing the numbers of evergreen conifers.  

Urban populations derive numerous personal benefits from urban greenery that include reduced stress and increased quality of life, as well as healthier birth weights for newborns and more productive workplaces in what can potentially be more aesthetically-pleasing communities. Indeed, at no point are the aesthetic benefits of evergreen conifers more apparent then when deciduous leaves have turned brown and the trees themselves have become barren. Our hope is that evergreen conifers grow to become better recognized as key components of green infrastructure systems that can offer significant returns through their ecosystem services when they are incorporated into the design and installation of the contemporary urban forest.

 
Table 1: Coniferous trees that may be well-suited to urban conditions.

Common Name	Scientific Name	Zone	Ht (ft)	Soil	Evergreen?
Western Redcedar	Thuja plicata	~5-8	~100	Moist, nutrient rich	Yes
Chinese hemlock	Tsuga chinensis	6	~80	Moist to semi-dry	Yes
Incense cedar	Libocedrus decurrens	~5-8	~50	Moist well-drained to dry	Yes
Japanese cryptomeria	Cryptomeria japonica	~5-9	~60	Wide range of soil types	Yes
Dawn redwood	Metasequoia glyptostroboides	~4-8	~100	Wide range of soil types, can do wet soils and pollution well	No
Norway spruce	Picea abies	~2-7	~60	Wide range of soils types, prefers well-drained	Yes
Eastern red cedar	Juniperus virginiana	~2-9	~65	Wide range of soils types	Yes
Giant sequoia	Sequoiadendron giganteum	~6-8	~100+	Tolerant of dry soils, prefers moist, well-drained	Yes
Bald cypress	Taxodium distichum	~4-9	~70	Dry to saturated soils	No

For more information on selecting and establishing conifers in the urban environment:

Aurders, Aris G. and Derek P. Spicer.  2013. Encyclopedia of Conifers: A Comprehensive Guide to Cultivars and Species. Royal Horticultural Society and Kingsblue Publishing: London.

Clapp, J. C, Ryan, H. D. P., Harper, R. W. & Bloniarz, D. V. (2014) Rationale for the increased use of conifers as functional green infrastructure: A literature review and synthesis. Arboricultural Journal, 36(3):1-14.

Dirr, Michael.  2011. Dirr’s Encyclopedia of Trees and Shrubs. Timber Press: Portland, Oregon

Gerhold, H.D., N.L. Lacasse, W.N. Wandell.  2001. Landscape Tree Factsheets (including evergreens for screens), Third Edition.  The Pennsylvania State University.

Missouri Botanical Garden Plant Finder

Wyman, D.  1965. Trees for American Gardens. Macmillan: New York.

J.Casey Clapp, MS, is a graduate of the Department of Environmental Conservation, UMass Amherst
Richard W. Harper, PhD, is Professor and Extension Urban Forestry Specialist, Department of Environmental Conservation, UMass Amherst
At the time this article was written, all authors were located at the University of Massachusetts. The authors gratefully acknowledge Drs. Dennis Ryan and David Bloniarz.

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Upcoming Events

For details and registration options for these upcoming events, go to the UMass Extension Landscape, Nursery, and Urban Forestry Program Upcoming Events Page.

• June 4 - Conifer Diseases Walk, Arnold Arboretum, Jamaica Plain MA, 5:00 to 7:00 pm. Credits requested: 2 pesticide contact hours for categories 29, 35, 36, and Applicators License. Association credits: 1 MCA, 1 MCLP, 1 MCH. ISA, SAF, and CFE requested.

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Additional Resources

For detailed reports on growing conditions and pest activity – Check out the Landscape Message

For professional turf managers - Check out our Turf Management Updates

For commercial growers of greenhouse crops and flowers - Check out the New England Greenhouse Update website

For home gardeners and garden retailers - Check out our home lawn and garden resources

TickTalk webinars - To view recordings of past webinars in this series, go to: https://ag.umass.edu/landscape/education-events/ticktalk-with-tickreport-webinars

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Diagnostic Services

Landscape and Turf Problem Diagnostics - The UMass Plant Diagnostic Lab is accepting plant disease, insect pest and invasive plant/weed samples. By mail is preferred, but clients who would like to hand-deliver samples may do so by leaving them in the bin marked "Diagnostic Lab Samples" near the back door of French Hall. The lab serves 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. See our website for instructions on sample submission and for a sample submission form at http://ag.umass.edu/diagnostics. 

Soil and Plant Nutrient Testing - The lab is accepting orders for Routine Soil Analysis (including optional Organic Matter, Soluble Salts, and Nitrate testing), Particle Size Analysis, Pre-Sidedress Nitrate (PSNT), Total Sorbed Metals, and Soilless Media (no other types of soil analyses available at this time). Testing services are available to all. The lab provides test results and recommendations that lead to the wise and economical use of soils and soil amendments. For updates and order forms, visit the UMass Soil and Plant Nutrient Testing Laboratory web site. 

Tick Testing - The UMass Center for Agriculture, Food, and the Environment provides a list of potential tick identification and testing options at: https://ag.umass.edu/resources/tick-testing-resources.