Insects and Pests


This is the time of year when summer-blooming bulbs appear in every garden shop, hardware store, or even grocery store. Like a kid in a candy store, I can look at them for ages, dreaming of the colors and shapes that could appear in my garden. Recently the image on a package of Asiatic lily bulbs jumped out at me.

Dark Lady blend 2

The mix of antique-looking purples, creams, and pinks would be a beautiful addition our garden bed where limelight hydrangeas, pale drift roses, and a Dogwood Cornus florida with its pale cream blossoms touched with pink.

Asiatic lilies, along with Easter lilies, are true lilies in the genus Lilium and Fritillaria, in the genus Fritillaria, are members of the family Liliaceae. The trumpet-shaped blooms of the Asiatic lily flower in early summer and may face upright atop stems that have long, slim whorled leaves.

Oriental lilies, on the other hand, have flowers that are outward and downward facing and flower in late summer, including the very appropriately named hybrid ‘Stargazer’ lily whose outward-facing flowers appear to be looking up.

Stargazer 1

The Oriental lilies are more fragrant than the Asiatic so they are a better choice if that is what you desire in your garden or home. Both are great options for cutting and look lovely in containers with lower growing plants surrounding them. In addition, when grown in containers they can be swapped out with other plants after blooming or grow both groups in the same planter for a succession of blooms.

However, the bane of any true lily grower’s existence is the Lily leaf beetle, Lillioceris lilii. Both the larvae and the adult Lily leaf beetle feed on the foliage of true lilies, in fact they can totally defoliate a plant in a matter of days. This pest was first documented in the United states in Cambridge, MA, in 1992. In the subsequent years it became a major agricultural and economic pest of growers. The Lily leaf beetle is also known as the Scarlet lily beetle due to its bright red coloring.

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This insect lays its eggs and completes its entire life cycle on the same plant and can cause damage to both the stems and leaves. The bright orange-red, oval eggs are laid in groups of about 12 on the underside of the leaf in May. In 7-10 days the eggs will darken and then hatch out, allowing the larvae to feed on the underside of the leaf before moving to the upper leaf surface and the buds. They can be hard to control with insecticides as they use their own frass (excrement) as a barrier to cover themselves.

In another two weeks they will drop to soil to pupate emerging a week and a half later as adults.  The adults will continue to defoliate and weaken the plant. Neem can be used as a control but must be applied every 5 days or so. Scouting and handpicking are often the best option and I find that holding an open container below them as I scout helps to catch them if they attempt to drop to the ground. Fun fact: they will make a squeaky noise if squeezed or disturbed.

If you don’t enjoy the monitoring that is required to deal with the Lily leaf beetle or the disappointment of walking past your flower beds only to discover that your lilies have been stripped clean you may want to consider planting another dependable perennial bulb: the daylily.

Flower bed

Daylilies used to belong to the same family as the true lilies, Liliaceae, were reclassified in the family Asphodelaceae in the genus Hemerocallis. Since it was first formally described by Carl Linnaeus in the mid-eighteenth the Liliaceae family kept expanding until it encompassed over 300 genera and 4500 species. Most of these were grouped into Liliaceae simply because they had six tepals and a superior ovary. From 1998 to 2016 a phylogenetics (evolutionary history and relationships) study by the Angiosperm Phylogeny Group was key in recognition of the family Asphodelaceae. Within Asphodelaceae is the sub-family Hemerocallidoideae and the genus Hemerocallis in which resides the daylily.

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The ephemeral blooms of the daylily give it both its common name and Latin name as Hemerocallis comes from the Greek words hemera (day) and kalos (beautiful). To keep daylilies blooming longer I remove any spent flowers and also any of the large, bulbous seed capsules that may appear. Daylilies will grow in full sun or part shade in most soil types although like it slightly acidic, perfect for Connecticut gardens. A bit of a 5-10-5 fertilizer at planting and then each spring when growth appears is all that it needs.

The one pest of daylilies that I have to deal with each year is the metallic-brown Oriental beetle (Anomala orientalis). The adult beetles are attracted to the open blooms and will nestle themselves right down into the center of the blooms.

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Its another pest that I control by handpicking, dropping them into a container of insecticidal soap. I don’t mind though as this activity gets me up close and personnel to the beautiful blooms and also reminds me to deadhead as I go along.

Susan Pelton

All images by S. Pelton, UConn

Black knot of plum and cherry, caused by the fungus Apiosporina morbosa, may be overlooked during the growing season when the leaves are hiding the galls, but this time of year they are hard to miss, especially when they are as abundant as they are on the tree in the photo below.

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UConn Photo

This is a serious disease of these trees and can eventually kill susceptible varieties. Management options include sanitation, resistant varieties and properly timed fungicides.

Where manageable, prune out all galls during the dormant season and dispose of them off-site, burn or bury them. This is because even removed galls may still produce spores that can cause new infections. Prune  6″ below the visible edge of the gall because the fungus can be invading the wood in that area prior to gall development.

This disease can affect both orchard and ornamental varieties of plum and cherry but some of the tart cherries are less susceptible. Native wild cherries are hosts of the disease and provide a reservoir of inoculum for orchards and ornamentals. It’s helpful to remove those nearby where possible. For new plum plantings (fruiting/orchard), ‘President’ is highly resistant. Moderately resistant options include ‘Methley’, ‘Milton’, ‘Early Italian’, ‘Brodshaw’, ‘Fellenberg’, ‘Shiro’, ‘Santa Rosa’ and ‘Formosa’. ‘Shropshire’ and ‘Stanley’ are considered quite susceptible.

Here’s how disease develops: Infections occur in the spring on new growth from spores produced on the surface of 2+ year old galls. Spores are produced and spread during rainy weather and shoots must remain wet for a period of time for the spores to germinate and initiate an infection. Infections can occur at temperatures of 50°F or higher when water is present for the required period of time. Over the course of the first summer, a small greenish brown swelling develops. By the end of the second summer, the gall or knot becomes hard, rough and black. These galls begin producing spores the following spring. Galls expand in size each year until the branch is girdled (killed all the way around) and then they die. Once a twig or shoot is girdled, the portion beyond the gall can’t get any water or nutrients and dies as a result. Sometimes, larger branches and trunks can become infected, presumably through wounds.

What if you have a susceptible tree and want to prevent this disease? If you know you have a source of infection (hosts with galls nearby, either wild or on a neighboring property) and you’ve had some infections, keep up with the monitoring and pruning, fertilize and water as necessary to prevent stress, and use preventive fungicides, such as lime sulfur during dormancy (organic option) or chlorothalonil or others labeled for this disease. Other than lime sulfur, applications should be made as directed on the label beginning at bud swell and until new terminal growth ceases.

More information on this disease and its control: Black knot fact sheet

By J. Allen

 

‘An herb whose flowers are like to a Lions mouth when he gapeth.’
Copious Dictionary in three parts by Francis Gouldman

After the 5th mildest February in Connecticut on record for the past 113 years it felt as if we were going to just saunter into spring this year. Walking around the yard on the first day of March I saw the usual signs of late winter including the new buds of Hellebore peeping through last year’s old foliage and even a brave little slug that had emerged from the soil.

But the next day March came in like a lion with winds gusting to 74 mph at the Ledge Lighthouse in Groton courtesy of a Nor’easter that also brought snow and drenching rains, days later we had 12-18” of heavy, wet snow across the state and today, another 6-10”. Fortunately, hellebore is able to withstand a little bad weather.

Helleborus is known as winter rose, Christmas rose, and, most familiarly to me because of when it blooms, Lenten rose. Its scientific name was given by Carl Linnaeus in 1753 and comes from the Greek ‘helléboros’ which breaks down into heleîn ‘to injure’ and borά ‘food’ due to the toxic nature of all parts of the plant. Two kinds of hellebore were known before 400 BCE:  the white hellebore of the Family Melanthiaceae was believed to have been used as a laxative by Hippocrates and the black hellebore, melanorrhizon (black-rooted), a member of the Ranunculaceae family. It is the latter group that most garden hellebore belongs to, one that also gives us Delphinium and Clematis (below), Buttercups, Ranunculus, and Anemone.

Hellebore originated in the mountain areas and open woodlands of the Balkans but some species also come from Asia (H. thibetanus) and the border of Turkey and Syria (H. vesicarius). In the centuries since hellebore has found its footing in gardens around the world where it continues to be a favored choice as a ground-cover with dark, shiny, leathery leaves.

It is so popular that Helleborus x hybridus was chosen the 2005 Perennial Plant of the Year from up to 400 nominations by the Perennial Plant Association. Plants are chosen by the PPA for their low-maintenance, wide range of growing climates, multiple season interest, availability, and relatively pest and disease-free care. It’s no surprise that Hellebore made the cut.

Helleborus by Dawn Pettinelli

Image by Dawn Pettinelli

It grows in USDA zones 5a to 8b which makes it very well-suited to Connecticut even though it is not native. It can tolerate shade to part-shade and does well in moist, well-drained soil with a pH range of 5.7-7.0.  Lower pH levels can lead to calcium and magnesium deficiencies. Interestingly, once established, hellebore is very drought-tolerant and even drooping leaves will bounce back unharmed when they are re-hydrated. Due to the fact that its leaves contain nasty-tasting alkaloids it does not get eaten by deer or rabbits and is considered toxic to humans and animals when ingested.

Helleborus orientalis late winter

 

Those same alkaloids can be a problem for people with sensitive skin so it is wise to wear gloves when working with hellebore. I trim the foliage back in late winter, at the start of March if there isn’t any snow cover, so that the emerging flower buds aren’t hidden by the old growth.

If Botrytis cinerea, a grey mold, was a problem on hellebore foliage then infected plant material should be removed in the fall so that it doesn’t overwinter.  Late winter is also a good time to apply a slow-release, balanced fertilizer that will ensure ‘blooms’ that will last for a month or more.

 

I say ‘blooms’ because what appears to be petals are actually tepals that protect the small, barely noticeable flower buds. Sepals are usually green but when they are similar in appearance and color to petals they are called tepals. Other plants that have colored tepals are Orchids, Day lilies, Lilies, Lily of the valley, Tulips, Magnolia and Tulip poplar.

On the hellebore the vintage-looking colors of the tepals range from a pure white to a dusky rose to a deep, almost black, plum. Most tepals become green-tinged as they age and many are veined, spotted, or blotched with shades of pink, purple, or red. The 2-3” ‘blooms’ generally hang or droop down so it is sometimes hard to see the nectaries that provide food for the early pollinators.

There are few insects that bother hellebore but one is the Hellebore aphid which will feed on sap from the flowers and foliage, excreting the honeydew that may lead to the growth of sooty mold. Cucumber mosaic virus can be vectored by feeding aphids and shows itself in light and dark green mottling on Hellebore foetidus.

HL

Image by RHS

 

 

H. foetidus, also known as stinking hellebore or dungwort is found in the wild in southern and western Europe in addition to cottage gardens. Its foliage gives off a pungent smell when crushed and it has another insect pest particular to it, the Hellebore leaf miner, which, as its name suggests, will tunnel into the foliage creating the damage shown to the left.

 

 

There are many commercially available varieties of hellebore and hybridizing has created a color palate that now includes reds, grays, yellows, and greens. The Picotee variety have narrow margins of a darker color. Semi- and double-flowered hellebore have two or more extra rows of tepals and the anemone-centered variety have a ring of shorter curved petals closer to the center which drop off after pollination. A visit to your favorite nursery or garden center is sure to provide you with many selections.

Helleborus by Lisa Rivers

Image by Lisa Rivers

You can put them into the ground as soon as it is workable. As Hellebore do not grow more than 18” high and have flowers that hang down they are best appreciated when viewed from close proximity. Plant them in an area that you walk past often and enjoy them for years to come.

Susan Pelton

All images by Susan Pelton unless noted

Did you notice off-color leaves on your broadleaved evergreens, such as azalea, rhododendron or Andromeda last year?  These popular landscape shrubs are sometimes attacked by lace bugs and their feeding damage results in small, yellow to brown flecks on the leaves. When there are many of these, the whole leaf, and even the whole shrub, can look off color from a distance.

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Leaf discoloration caused by the feeding of lace bugs. Photo credit: William Fountain, University of Kentucky, Bugwood.org

What are lace bugs? They’re insects in the family Tingidae and have piercing and sucking mouth parts. They are small – the adults are only 2-3 mm in length. They are quite distinctive looking. Adults have flattened bodies with lacy looking wings that give them their common name. The species on broadleaved evergreens appear black and white. Nymphs are quite dark in color, up to about half the size of the adults, depending on their growth stage (instar) and are covered with dark spines.

 

It’s easy to miss these pests as the cause of leaf discoloration because the feed and reproduce on the lower leaf surfaces. They pierce leaf cells and suck out the juicy contents, resulting in cell death. So a lot of this type of injury due to a high population can result in reduced photosynthesis that in turn leads to poor plant health, leaf drop and reduced flowering.

Lace bugs that attack broadleaved evergreens overwinter in the egg stage. Eggs are laid in the leaves of the veins, mostly on lower leaves, and then covered by the female with a cement or varnish like material. Spring hatch occurs typically in May in the northeast. Nymphs begin feeding immediately and go through five nymphal stages or instars before becoming adults. Under favorable conditions, the entire life cycle may be completed in one month. Depending on lace bug species, there may be 2-4 generations per year in Connecticut.

To protect plant health and also to prevent unsightly discoloration of the leaves, monitor for lace bugs early in the season on susceptible plants, especially if they have evidence of injury from the year before. Nymphs and adults can be sprayed off plants with a strong stream of water or they can be treated with horticultural oil or insecticidal soap. Both of these products must coat the pests to kill them so thorough coverage of the leaf undersides is required. Inevitably, some individuals or eggs will survive so a second application may be necessary. Prevention of damage before it gets too severe is important because leaf discoloration will persist for a year or more.

Both azalea and rhododendron lace bugs are more likely to build up to high, damaging populations on plants in sunny locations. The Andromeda lace bug can cause a lot of trouble in both sunny and shady sites.

As mentioned above, there are a number of susceptible plants found commonly in northeast landscapes. The lace bugs have quite narrow host ranges as shown below:

               Lace bug species                                                          Host plants

Andromeda lace bug Japanese Andromeda, Leucothoe
Azalea lace bug Azalea and mountain laurel
Rhododendron lace bug Rhodendron and mountain laurel
 

By J. Allen

We may be in the throes of winter but there is a place in New England where the most beautiful and delicate flowers bloom year-round. These flowers are presented in all their glory in displays that have recently been upgraded to enhance the viewing experience. These flowers and specimens will never wilt or fade, they are forever captured in a state of perfection. These are neither fresh, dried, preserved, nor photographed flowers. They are the Ware Collection of Blaschka Glass Models of Plants, the famous “Glass Flowers” of Harvard University.

I first saw the Glass Flowers several years ago when our daughter Hannah, then a student at MIT, suggested a visit to the nearby Harvard Museum of Natural History in Cambridge, Massachusetts. As with most natural history museums the collections ranged from wildlife specimens and fossils to minerals and gemstones. But it was the Glass Flowers exhibit that Hannah knew that I would enjoy most.

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Although it is familiarly known as the Glass Flowers this exhibit actually represents over 4,000 models of 830 plant species and includes incredibly realistic and detailed models of enlarged flowers and anatomical sections of the floral and vegetative parts of the plants (clockwise from top left: Banana, Verbascum thapsus/Common mullein, and Gossypium herbaceum/Wild cotton).

Prior to 1886 the Harvard Botanical Museum, under the direction of George Lincoln Goodale, used pressed plant specimens, wax models, and papier-mache as samples for study. Pressed specimens are of limited teaching value as they are 2-dimensional, dried, and lacking in color, wax models and papier-maché were rough and didn’t stand up well. Around this time, Goodale saw some glass models of marine invertebrates in the Harvard Museum of Comparative Zoology that had been created by the father and son partners Leopold and Rudolf Blaschka from Hosterwitz near Dresden, Germany. He contacted Leopold Blaschka who then made and shipped a few botanical specimen samples which even though they were damaged in US Customs still showed the possibilities of further work.

There were other glass-blowers at the time and it was said that no-one could replicate the secret methods employed by the Blaschkas. The Boston Globe said that the glass flowers were “anatomically perfect and, given all the glass-workers who’ve tried and failed, unreproducible”. But in fact, there were no secret methods employed and their techniques were commonly known to other artisans. In addition to glass the Blaschkas used wire supports, glue, paint, and enamel in their work. Their method melted glass over a flame or torch which they controlled with foot-powered bellows in a technique known as lampworking. This differs from glassblowing which uses a furnace as the heat source. The molten glass was manipulated, pinched, and pulled with tools to achieve the desired forms. The finished specimens were occasionally formed from colored glass but were often hand-painted.

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Leopold Blaschka credited their ability in this way, “get a good great-grandfather who loved glass; then he is to have a son with like tastes; he is to be your grandfather. He in turn will have a son who must, as your father, be passionately fond of glass. You, as his son, can then try your hand, and it is your own fault if you do not succeed. But, if you do not have such ancestors, it is not your fault. My grandfather was the most widely known glassworker in Bohemia.” Schultes, Richard Evans; Davis, William A.; Burger, Hillel (1982). The Glass Flowers at Harvard. New York: Dutton.

(at right, Caroline and Leopold Blaschka, seated, Rudolf Blaschka, standing)

 

The original 10-year contract between the Blaschkas and Harvard commissioned the work at a rate of 8,800 marks per year ($3,533 US dollars) or approximately $91,565 in 2017. The funding came from a former Radcliffe College botany student of Goodale’s, Mary Lee Ware and her mother, Elizabeth Cabot Ware, members of a wealthy Boston family. Additionally, all freight charges were covered by Harvard.

So, the artisans have been commissioned. Remember, the year is now 1890, film photography is in its infancy and it is about 100 years before the internet is available to the public. So how do two glassmakers in Germany research botanical specimens from all over the world? Well, some plants were sent from America and raised in the Blaschka’s garden. Other plants that were tropical or exotic were viewed in the royal gardens and greenhouses of the nearby Pillnitz Palace (below images). Rudolf Blaschka traveled to Jamaica and the United States in 1892 to make drawings and collect specimens. Leopold died in 1895 but Rudolf continued to work until his retirement in 1936. Rudolf had no children and had never taken on an apprentice so there was no one to take over from him ending a 400-year-old dynasty.

But the legacy of Leopold and Rudolf Blaschka lives on in over 10,000 glass models that are in museums the world over. Although the greater number of these are marine specimens it is the Glass Flowers that are most famed. The Glass Flowers encompass 164 families and 780 species in 850 full-time models. There are 4300 detailed models of individual floral and vegetative parts that capture every detail, right down to a grain of pollen as in the example of Lupinus mutabilis (Lupine) shown below.

Glass Flowers Exhibit Harvard Museum of Natural History

There are models that show the fungal and bacterial diseases of fruits in the Rosaceae family that includes apples and pears (The Rotten Apples, shown below).
Rotten apples

Others show insects in the act of pollination such as their depiction of a male fruit fly on an orchid, top image, or the bee on Scotch broom, below. Plants are exhibited from the simplest to the most advanced in the order of evolution.

Glass Flowers Exhibit Harvard Museum of Natural History

Cytisus scoparius (Scotch broom) with bees

This is not an exhibit that you would speed through. Each specimen is so enthralling that it is difficult to move on to the next one. The fact that every item there was created by only two men is mind-blowing and can be attested to by the tens of thousands of visitors each year. If you haven’t been to the exhibit I highly recommend it and if you have been in the past in would be worth going to see it in its restored glory. Visit the Harvard Museum of Natural History site for additional information and to view their videos of the Restoration and the Rotten Apples.

Susan Pelton

The Glass Flower images shown here are the property of Harvard University.

snow and tree

As I sit here inside, watching the cold wind blow and snow pile up outside the warmth and safety of my little writing spot, I wonder just how all those living beings outside are surviving. Trees are swaying in the wind, and birds trying to visit the feeder are forced to alter flight plans while sporting ruffled feathers. The only animals I see are hunkered down squirrels. And just where did the insects go?

A little research tells me all of the annual plants are dead. They completed their life cycle in one year going from germinating a seed to producing seeds which are waiting winter out to make new plants in the spring. In my vegetable garden I call them volunteers. You know those tomato seeds that germinate from last year’s rotted tomato fruit that dropped to the ground and its seed volunteered to grow where I didn’t put this year’s crop. The seed survived through the winter, not the plant. Annual weeds drop seed in this manner, too.

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Perennial plants are a different story, although their seeds can do the same overwintering as annuals, the existing plant can live through the winter to grow another year, hopefully for many years more. Trees and shrubs are woody perennials that have woody above ground structures and roots that overwinter. Herbaceous perennials overwinter their roots and crowns only. The above ground portion of the plant dies back, but the crown and roots are alive at level or below ground. Perennial plants go dormant, living off of stored food until warmer weather returns. Storage organs of plants are the thick roots, rhizomes and bulbs. Just how they prepare themselves to make it through the winter happens at the cellular level long before freezing temperatures begin.

Plants are triggered by the amount of light and the amount of dark they experience, and lower night temperatures signal to get ready for winter rest and dormancy. Different species have varying light and temperature levels signals. Deciduous trees and shrubs must begin the process of losing their leaves by first stopping the production of their food. We notice it in slower growth and in the leaf color. The leaves are the food factory of the plant where photosynthesis happens. Carbohydrates are made then stored in roots and woody parts of the tree or shrub. Lots of light and water results in good growth and food storage, but when light amount lessens, leaves slow down production. Chlorophyll is also produced during photosynthesis, giving the leaf a green color. Once the leaves stop working, no more chlorophyll is produced and the other plant pigments of red and yellow are exposed now that there is no green chlorophyll to cover them. This is when we see beautiful fall foliage. The next change happens in a specialized layer of cells at the point where the leaf stem (petiole), attaches to the twig called the abscission layer. These cells enlarge and harden to choke off water flow to the leaves and the leaf slowly dies and falls off.

tree in fall

The next cellular change is called cold hardening. It happens within the vascular system containing the plant juices and water. If water inside the cells freeze, it will rupture the cells, permanently damaging the plant. The cold hardening process increases the sugar content of the water, and makes other protective chemicals, lowering the freezing level of the plant liquid. Basically the plant makes its own antifreeze. Cell walls are also changed to allow water leakage into spaces just outside the cell so if crystals do form, damage will be avoided. The acclimation of all these changes makes the plant able to tolerate below freezing temperatures. Fall pruning or fertilizing with nitrogen during August and September stimulates new growth interrupting the cold hardening process.

Evergreen trees and shrubs have thick leaves with waxy coatings to prevent moisture loss. Some broadleaved evergreens have gas exchange openings called stomata on the underside of the leaf. In very cold weather the leaves will curl as the stomata close to prevent moisture loss. Rhododendrons are a good example. Evergreen plants will continue to photosynthesize as long as there is moisture available, but much more slowly during the winter.

rhododendron curled in snow

Animals and insect have the ability to move, unlike plants. They can migrate, hibernate or adapt to winter’s cold. Certain birds migrate to warmer areas and better food sources. Hummingbirds, osprey, wood ducks and song birds fly south, and some birds from far north in Canada come south to spend the winter here. Juncos, snowy owls and bald eagles summer at a higher latitude and spend the winter nearer to us. They go where they can find food.

Some animals go into a winter dormancy or hibernation. This phase consists of greatly reduced activity, sleep or rest, and lower body temperatures while their bodies are sustained from stored fat. Bears, woodchucks, skunks, bats, snakes and turtles all have true hibernation, not waking until light levels increase and food sources begin to be available again. Bears and bats find caves, woodchucks, and skunks dig tunnels, snakes and some turtles burrow into soil and leaf litter, all in protected sites.

woodchuck at entrance to tunnel

Woodchuck at the entrance to his tunnel where he will spend the winter.

Other animals such as chipmunks have underground burrows lined with stored nuts and other food. Beavers do the same in lodges they build just above water, and line with stored logs to feed on during the winter. They sleep for long periods, only waking to eat and if maybe take a short walk above ground before returning to their den. Fur bearing animals will grow a thicker winter coat to help keep them warm, and may be a whiter color to provide camouflage in the snow.

Voles are active all through the year. In winter, they will tunnel through the snow, just on top of the ground looking for plants material to eat. They will strip the bark off of young trees and eat the roots. Voles store seeds and other plant matter in underground chambers. Mice are active and breed year round, living in any protected nook or cranny they can find, including our homes. They store food in hidden spots away from human and predator activity. Check for mice tracks around your foundation after a freshly fallen snow to see if mice are using your house for their winter quarters. Moles are active deep underground, below the frost line, in an elaborate array of tunnels. They feed on soil dwelling insects throughout the winter. I guess you could say they go ‘south’ in the soil profile during cold weather of winter.

Squirrels do not migrate nor hibernate, they adapt. They are active all winter, raiding bird feeders, and feeding on stored nuts. They grow a thicker coat of fur and fat for winter. Squirrels make great nests high in trees, well insulted with leaves. Several grey squirrels will share a nest to keep warm. They are often too quick to get a close up photo!

squirrel tail

Insects as a group are very large and diverse. Some migrate in their adult stage such as monarch butterflies and some species of dragonflies. Others overwinter in pupal stages like the chrysalis’ of spice bush swallowtails or cocoons of Cecropia moths.  Others adult and immature insects, depending on species, enter a state of diapause, similar to hibernation in animals, to overwinter during the winter. Diapause is a dormant semi-frozen state for some insects.  And like plants, changes at the cellular level occur, too. These insects produce an alcohol-like chemical and added sugars to the moisture in their bodies to prevent freezing, just like vodka will not freeze when placed in our home freezers. Insects will first seek out a protected place in the soil, leaf litter or under lose tree bark or rotten logs.

The brown and orange woolly bear caterpillar burrows into the forest floor to spend the winter as in its larval stage. In spring it will come out of its dormancy to pupate, later becoming an Isabella tiger moth.

woolly bear

Other insects lay eggs singly or in mass groupings, which are equipped to live through the winter and hatch when conditions are good again. Gypsy moths spend the winter as egg masses, tolerating down to -20 F temperatures. Crickets are another insect group which lays eggs in the fall on the ground that will provide a new generation of night songs for us to enjoy the next summer.

Gypsy moth egg cases, p.cooper photo

Gypsy moth egg mass will overwinter on this tree bark. Hatch will be in late spring.

-Carol Quish

tulips

 

 

 

Every growing season brings a variety of inquiries into the UConn Home & Garden Education office, either by snail mail, email, or in person. This year was no exception and I would like to share some that I found particularly interesting.

As we are entering the Christmas season I will start with an image of a Christmas cactus with raised bumps on its leaves. Although they were the same color as the leaf they had a translucent appearance when viewed with the light from behind. These blisters are edema (oedema)are the result of a disruption in the plant’s water balance that causes the leaf cells to enlarge and plug pores and stomatal openings. Moving the plant to a location with more light and watering only when the soil is dry can control edema.

Edema on Christmas cactus

Christmas cactus with edema symptoms

The cold of winter can cause problems that sometimes aren’t apparent until later in the year. Tree trunks that are exposed to southern light during the winter can suffer from sunscald and frost cracks. Sunshine and warm daytime temperatures can warm a tree enough so that the sap begins to run but the nighttime temps will cause the sap to freeze and expand, weakening the bark and resulting in vertical cracks. Dogwood with sunscald (on left) and willow with frost crack (on right) are among the susceptible species.

 

There were several incidences of huge populations of black cutworm larvae emerging in the spring including a group that appeared to be taking over a driveway! The Noctuidae moth can lay hundreds of eggs in low-growing plants, weeds, or plant residue.

The wet spring weather that helped to alleviate the drought of the past two years also had an effect on the proliferation of slime molds, those vomitus-looking masses that are entirely innocuous. The dog stinkhorn (Mutinus caninus) is another fungus that made several appearances this year.

Hosta plants exhibited several different symptoms on its foliage this year and the explanations were quite varied, from natural to man-made. The afore-mentioned wet spring and summer or overhead watering systems can cause Hosta to have the large, irregular, water-soaked looking spots with dark borders that may be a sign of anthracnose (the below left and center images). In the image below on the right the insect damage that shows up as holes that have been chewed in foliage may be caused by one of Hosta’s main pests, slugs.

But one of the more enigmatic Hosta problems presented itself as areas of white that appeared randomly on the foliage. Several questions and answers later it was determined that the Hosta in question was very close to a deck that had been power washed with a bleach solution! Yeah, that will definitely give you white spots.

Bleach damage 3

That bleach bath also affected a nearby coleus (below on left). Coleus downy mildew (Peronospora sp.) also likes the cool the cool temperatures and humidity of spring (below on right). The gray-purple angular blotches of this fungal disease were first observed in New York in 2005. Fungicides can be helpful if used early and thoroughly, and overcrowding and overhead watering should be minimized.

The grounds of the residence where my in-laws live have a lot of flowering plants in the landscape and as we walked one evening I noticed that the white roses had spots of red on them. These small, red rings are indicative of Gray mold (Botrytis cinerea), a necrotrophic fungal disease that is also a common problem in grapes called botrytis bunch rot. The disease is a parasitic organism that lives off of the dead plant tissues of its host.

The fungus Gymnosporangium clavipes, cedar-quince rust, on Serviceberry warranted several calls to the center due to its odd appearance. The serviceberry fruit gets heavily covered with the aecia tubes of the rust which will release the aeciospores that infect nearby members of the Juniper family, the alternate host that is needed to complete the cycle of the infection.

Two other samples that came in, goldenrod (below on left) and sunflower (below on right), shared unusual growths of foliage. Sometimes plant aberrations can be the result of a virus (such as rose rosette disease), fungus (such as corn smut fungus), or, like these samples, phytoplasma. Phytoplasma is the result of bacterial parasites in the plant’s phloem tissue and can result in leaf-like structures in place of flowers (phyllody) or the loss of pigment in flower petals that results in green flowers (virescence). Phytoplasma parasites are vectored by insects.

A frequent question revolves around ‘growths’ of a different kind, in particular the white projections that can cover a tomato hornworm. These are the pupal cocoons of the parasitic braconid wasp. The female wasp lays its eggs just under the skin of the hornworm and the newly hatched larvae will literally eat the hornworm to death. As the larvae mature they will chew their way to the outside where they will spin their cocoons along the back and pupate. As the hornworm is effectively a goner at this point they should be left undisturbed so that the next generation of wasps will emerge to continue to help us by naturally controlling this tomato pest.

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Tomato hornworm with braconid wasp pupal cocoons

 

Another wasp that was caught in the act was the cicada killer wasp (Sphecius speciosus), a large, solitary, digger wasp. Cicada killers, also called cicada hawks, are so called because they hunt cicadas to provision their nests. It is the female cicada killer that paralyzes the cicada and flies it back to her ground nest. The male cicada killer has no stinger and although its aggressive nature can seem threatening to humans, the male spends most of its time grappling with other males for breeding rights and investigating anything that moves near them.

Cicada killer wasp

A cicada killer wasp paralyzes a cicada

 

Speaking of noticing what’s going on around you, as my husband was walking past a False indigo (Baptisia australis) in July he heard a strange cracking sound and called it to my attention. The plant in question was outside of a gym on the Hofstra University campus where our son’s powerlifting meet had just ended. As many lifters exited the building amid much music and commotion we stood their staring at the Baptisia, heads tilted in that pose that is more often found on a puzzled dog. The bush was indeed popping and cracking as the dried seed pods split open!

 

But none of our inquiries approach the level of oddity reported by a retiree in Karlsruh, Germany, who thought that he had found an unexploded bomb in his garden in September. Police officers called to the scene discovered not a bomb but in fact an extra-large zucchini (11 lbs.!) that had been thrown over the garden hedge.

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This is not an unexploded ordnance!

 

I look forward to next year’s growing season with great anticipation!

Susan Pelton

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