Red-Spotted Purple butterfly on a native Eupatorium in September. Photo: M. Talabac
Q: A lot of my new native plant garden beds contain species that bloom in spring and early/mid-summer. What can I add for pollinators that blooms late?
A: Fortunately, there are numerous late-season nectar sources, though most are sun-loving species. They are very attractive to migrating Monarchs and any other butterfly on the wing in late summer and autumn, plus bees, wasps, beetles, flies, and plenty of other insects. Seed-eating birds also appreciate the food source once the seeds of those plants ripen by the end of the growing season; nature’s bird feeders.
Lots of late-flowering native plants are in the aster family, including: Ironweed (Vernonia); Goldenrods (Solidago and Euthamia); Asters (formerly genus Aster, now named Doellingeria, Eurybia, Ionactis, or Symphyotrichum); Cut-leaved Coneflower (Rudbeckia laciniata); Blazing-star (Liatris); Elephant’s-foot (Elephantopus); Beggarticks (Bidens); Wingstem (Verbesina); Helen’s Flower (Helenium); perennial Sunflowers (Helianthus); Climbing Hempvine (Mikania scandens); and the Eupatorium group (several common names and genera; Eupatorium, Eutrochium, Conoclinium, Ageratina).
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension. Our horticulturists are available to answer your questions online, year-round.
The best kind of green thumb…a perch for a Luna Moth. Photo: M. Talabac
Q: I found a huge green moth on my front door! What is it, and do they visit flowers so I can attract more?
A: This beauty is one of my favorite insects…a Luna Moth, a native species and one of our largest North American moths. Their green color, rare among our local moths and butterflies, ranges from medium to pale celery-green or a pistachio ice cream hue. Their long hindwing tails and eyespots combine to give them a look resembling an elephant’s face. I imagine those eyes give foraging birds a moment’s pause, though the bigger predator for these moths is probably bats since they are night-flying.
Adults have vestigial mouthparts and cannot feed, so flowers won’t attract them. They rely on body fat stored from the caterpillar stage (which grows gleefully big) to fuel their brief search for mates and egg-laying sites. You can support breeding populations by caring for caterpillar host plants, which for Luna include hickory, walnut, sweet gum, and white oak, among other trees.
Avoiding pesticide use in home landscapes is of critical importance, though communities that are subjected to aerial forest sprays for Spongy Moth or other pests may, unfortunately, experience population declines, even though such treatments are relatively targeted. Gardeners attempting to rid a tree of nuisance aphids, Spotted Lanternfly, scale, and other insects could inadvertently affect harmless species like these moths in the process. Remember that any tree roots infiltrating a lawn that is treated with a systemic insecticide (like for grubs) might absorb some of those chemicals and transport them into the canopy.
Light pollution is another big detriment to these and many night-active insects (like fireflies), with home landscape accent lighting, porch lights, street lights, and other sources of illumination interfering with their ability to navigate at night.
For anyone curious about moths, I encourage you to participate in or follow National Moth Week, a citizen science project taking place the last full week of July each year. Check out what visits your porch lights, flowers (there are some day-flying nectar-feeding moths), and see if you can ID the caterpillars that wander the landscape or chew holes in tree, shrub, or perennial leaves. So few are truly pests so you won’t need to worry about managing them; leave them to fulfill their part in the food web of our local ecosystem.
You can also sign up to learn about nighttime pollinators and how to support them in the upcoming free webinar: “Working the Night Shift: Pollination After Dark,” taking place on August 3 from noon to 1:30 pm.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension. Our horticulturists are available to answer your questions online, year-round.
Patent-leather beetle on a rotting log. Photo: M. Talabac
Q: I found several of these beetles in an old decaying stump and am concerned for my healthy trees. Will they attack live trees?
A: No, these beetles feed on rotting wood and the fungi decaying it, and they pose no threat to other trees. Several common names are given to them: Patent-leather Beetle, Bess Bug, and Horned Passalus.
These insects have a rare life history in that they live in groups and provide parental care for their larvae, feeding them pre-chewed rotting wood, likely for over a year while the young mature slowly.
The feature I find the most entertaining about them is their ability to squeak. Both adults and larvae can stridulate, which means they use one body part to rasp against another to create noise. The purpose of this is probably to communicate with each other. Cricket chirping and katydid calling are forms of stridulation, but in the case of these beetles, it produces more of a high-pitched sound akin to a person making “kissy” noises at a pet.
Interestingly, Iowa State University’s BugGuide web page for Bess Beetles speculates that the “bess” part of its name might derive from baiser, French for “to kiss.” (Or it’s derived from the fact that their forward-facing jaws can pinch, though I’ve never been bothered and I pick up these beetles every time I see them because they’re fun to find. “Petting” them sometimes makes them stridulate, which is always endearing.)
Wood-recycling insects like these are great to have around and rarely if ever pose a risk to healthy plants. Not only do they get those old stumps and logs out of the way for free (even though it can take a while), but both they and the fungi they work with are a means to make the old tree’s nutrients available again to the rest of the ecosystem.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension. Our horticulturists are available to answer your questions online, year-round.
Q: Do you have any information related to the “no mow” movement? We have a very weedy lawn and are considering replacing it with Dutch clover. Is that a good idea? Bad idea?
A: We do not recommend replacing lawn outright with clover. Clover goes dormant in winter, losing leaves, which leaves the soil surface exposed to weed seed colonization and potential erosion. The clovers used in lawns are also non-native and would not support the majority of our native bees (which are specialists, relying on certain native species for pollen, nectar, or plant oils). Generalist bees can use clover or other blooms but these tend not to be the local bees needing the most support from garden plantings.
If you prefer to augment your existing lawn with clover, consider microclover, which is a dwarf and less-aggressive variety of white clover that cohabitates with turfgrass more cooperatively. While not solving any of the other above issues, at least this is a more suitable choice when using clover in a lawn. Our Lawns and Microclover page provides some pros and cons plus links to a more detailed publication (PDF document) about how to go about creating and maintaining this mix.
Chanticleer’s flowery lawn interpretation, more of a no-mow-ever than a no-mow May situation, and thus of more benefit to wildlife. Photo: M. Talabac
Opinions among professional horticulturists about “No Mow May” actions are mixed because there are both benefits and drawbacks that it creates. You will probably find both proponents and opponents to this practice in Extension and other science-based web publications and articles. The main benefit of the movement is its ability to get gardeners thinking about their landscaping choices and actions and the impacts of these on the ecosystem. (And that’s a good thing!) That said, most of the flowering lawn weeds that no-mow is supposed to protect are non-native and do not support many of our native bees, and allowing them to set seed only enables them to spread further in places where native plants should ideally be growing instead.
For gardeners interested in having turf serve double-duty as a “bee lawn” – that is, intentionally planted with seed mixtures containing low-growing flowering plants – the benefits and shortcomings of this approach are similar to those with clover lawn conversions or from reducing mowing for limited periods of time. University of Minnesota research shows that bee lawns do provide benefits for pollinators, including native ones. However, most commercially-available bee lawn mixes contain plants from Europe and/or Asia, and are perhaps not the best nutritionally for Maryland’s specialist bee adults or a resource they will be able to use for their young. Some Maryland native plants that can be incorporated into bee lawns, such as Self-Heal (Prunella vulgaris subspecies lanceolata), are not readily available in seed mixes here, and research on Maryland-native plants for use in bee lawns is not available at this time. Visit UMN’s “Planting and Maintaining a Bee Lawn” web page for more detail.
Prunellavulgaris. Photos: M. Talabac
Our energies and efforts aimed at benefiting insects, birds, and other organisms may be better spent creating native plant gardens alongside of (or in place of) lawns, which will not only serve specialist bees more suitably but also will support a variety of other native wildlife in the process. In any garden setting, including when plant selections are native-focused, using a diversity of plant species has several benefits: it can support a greater diversity of wildlife (including pollinators and beneficial insects that help suppress pests), it adds aesthetic and seasonal interest, and it increases the resiliency of the planting as a whole, because different species won’t have the same degree of vulnerability to any one issue (like drought or flooding) that may arise.
Native common fleabane (Erigeron philadelphicus) blooms in a front yard where a portion of the turfgrass was removed and replaced with little bluestem, switchgrass, and a mixture of flowering perennials. Fleabane supports a variety of native bees, solitary wasps, and other beneficial insects. Photo: C. Carignan
Not mowing lawns regularly also stresses the turf by creating a situation where, when mowing does resume, it’s removing much more of the turf’s leaf mass at one time, causing stress and interfering with its normal growth habit that creates a dense lawn. The “grazing response” that mowing triggers, promoting more low growth that fills-in gaps, won’t be happening to the same extent if the grass goes for weeks without being cut, especially as it diverts some energy for growth into producing pollen and seed. (This turfgrass flowering also might be a consideration for people with bad grass pollen allergies.)
This topic of bee resources in lawns as addressed by the no-mow movement is touched upon by wildlife biologist Sam Droege in the native bee special episode of the University of Maryland Extension Garden Thyme Podcast from last summer.
Lawn alternatives, even if not purely native species, are another option when dealing with a lawn that is struggling. While a healthy lawn is providing more environmental services (carbon sequestration, erosion control, nutrient filtering, etc.) than a struggling lawn, if you do not wish to devote resources to improving its health and vigor, then converting those areas to non-lawn is more practical, even if a bit more expensive at first than just rehabbing the lawn. If a tolerance to regular foot traffic from people or pets is needed, then lawn is the best groundcover for this use and you might want to work to improve its health, but otherwise areas not being stepped-on can be planted with other species.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension.Our horticulturists are available to answer your questions online, year-round. You can also connect with your local County/City Extension Office and Master Gardenerlocal programs.
Immature Spotted Lanterflies are black with white spots when they first hatch in mid-April to May. Photo: Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org
Q: When will Spotted Lanternfly eggs hatch? We’ve had such warm spells this season that I worry it’ll be early.
A: Spotted Lanternfly (SLF) egg hatch, like the activity of many insects, is greatly dependent on temperature. Predictions for egg hatch in an average year begin around mid-April but can continue into May, so while it may not be early per se at this point, it still will be soon. As such, this is your last opportunity to be vigilant for egg masses to squish before the active, hopping, hard-to-catch juveniles appear.
Don’t panic – juveniles cause little plant damage to gardens when young – but eliminate any egg masses within reach if possible because this is a serious agricultural pest (vineyards, mainly) and it might help you avoid an inundation of nuisance lanternflies later. To be fair, many eggs are laid high in tree canopies, making them inaccessible, but others can be laid on piles of stone, fencing, car hubcaps, grills, outdoor furniture, honey bee hive boxes, and so on.
Spotted Lanternfly egg masses on wood. Photo: Emelie Swackhamer, Penn State University, Bugwood.org
Be advised that the quarantine zones in Maryland have recently been expanded, and records indicate that the abundance of this pest has grown in our central counties. Check our Spotted Lanternfly web page and information updated on the Maryland Department of Agriculture website for more details. An MDA entomologist presented a refresher webinar about SLF this past winter, which you can find on the UMDHGIC YouTube channel as “Spotted Lanternfly Update from MDA.”
Spotted Lanternfly webinar (1 hour, 11 minutes)
If you haven’t seen Spotted Lanternflies in your neighborhoods yet, be prepared to see them in the next year or two as the population expands. I don’t want to scare you, just make you aware this will probably be something you’ll have to experience sooner or later, and I definitely discourage the use of any pesticide to combat this insect if its use can be avoided. Pesticides used to kill SLF have impacts on other insects and organisms and we don’t want to contribute to ecosystem damage by using them when the SLF damage done to most garden plants will be minimal.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension.Our horticulturists are available to answer your questions online, year-round. You can also connect with your local County/City Extension Office and Master Gardenerlocal programs.
Lone Star Tick “questing,” or trying to sense a host so it can climb aboard to bite. Photo: M. Talabac
Q: I like the style of more natural gardens, letting leaf litter be my mulch, etc. I’m concerned about this encouraging ticks, though. Do I have to change how I garden?
A: It’s a legitimate concern given the diseases ticks can harbor and transmit, but ticks can appear even in more manicured and minimally-vegetated landscapes, so I would rather reap the rewards of having a biodiverse and “wilder” garden than restrict myself and still wind up with hitchhikers when I go outside. Besides, some of that wildlife attracted by having a medley of native plants and leaf litter habitat may very well be killing some of those ticks. (Or doing the next best thing, eating their small-animal hosts that carry the pathogens we worry about.)
We at the Home and Garden Information Center (HGIC) are often asked about yard perimeter sprays and treatments for ticks, but pesticide use is not our suggested solution. Even when reasonably effective, these products are temporary measures and probably not substantially different in terms of efficacy than simply treating your own clothes or exposed skin with a tick repellent and/or doing a thorough body check once you’re back indoors.
Chemicals used to suppress tick populations (like for lawn applications) are non-selective and don’t impact only ticks. Their close relatives, spiders and any mites that aren’t plant pests (fun fact: some mites eat pests) are definitely worth having in our landscapes. They’re valued partners in natural pest management but can be equally vulnerable to the effects of sprays marketed for tick control. Some pesticide ingredients are even more broad-spectrum than this, potentially affecting ground-dwelling insects and other organisms. As with mosquito management, it’s more sustainable to use personal protection to avoid bites and to landscape in an eco-conscious way to make full use of any existing natural checks and balances that keep tick populations down.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension.Our horticulturists are available to answer your questions online, year-round. You can also connect with your local County/City Extension Office and Master Gardenerlocal programs.
A rust gall on juniper with spore “horns” just starting to emerge. As soon as it rains after this point, the “horns” turn gelatinous and bright orange. Photo: M. Talabac
Q: I heard rust fungus can infect junipers but they aren’t worth spraying to treat. Is there anything else I can do to reduce the fungal spread from them to my other trees?
A: If you see and can reach fungal galls on the branches, clip them off. Some rust fungi (though not all) create a gall on their juniper hosts. Plant galls are tumor-like in that they’re clusters of malformed tissue, often in response to a pest or (in this case) an infection. When the weather starts to be consistently mild in spring and we receive enough rainfall, the galls where the fungus is spending the winter will begin to exude their spores.
These rust spores blow on the wind or wind-driven rain to vulnerable host plants like various members of the rose family. In our gardens, this includes apples and pears, hawthorn, serviceberry, quince, and crabapple. Fungus spores are extremely tiny, so how will you know what to look for? If the gall is producing orange goo, you’re missing the window since spores are already being dispersed. Ideally, remove all visible galls before this point, while they’re still hard and dry. Now is an excellent time to inspect junipers on your property for galls. Trim them off with hand pruners and toss them in the trash (don’t compost).
This is not a foolproof method for eliminating the risk of rust infection on other plants this year, but it certainly could help reduce the disease pressure. Fortunately, infections like cedar-apple rust, while an aesthetic nuisance from time to time, generally don’t cause serious damage to all hosts, though they can be more serious for some, like apple.
By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.
Have a plant or insect question? The University of Maryland Extension has answers! Send your questions and photos to Ask Extension. Our horticulturists are available to answer your questions online, year-round.
