goldenrod

One of many goldenrod species

Goldenrods, Solidago ssp., form one of the most interesting interrelationships between flora and fauna of the late-season flowering plants in New England. The name solidago is from two Latin words meaning ‘to make’ and ‘whole’, referring to its use as herbal remedies in the form of teas or compresses, among other uses. Goldenrods are perennial herbs that are members of the Asteraceae, or aster, family. Flowering from August through September, they are often found blooming together with Joe-Pye weeds and asters. The time of year that they bloom has made them a scapegoat for many allergy sufferers who believe they are to blame them for symptoms that are actually due to ragweed that flower at the same time.

 

honey bee on downy goldenrod Pamm Cooper

Honey bee on downy goldenrod.

 

Goldenrods naturally produce rubber, and Thomas Edison actually experimented with the cultivation process to increase the rubber content in the plants. George Washington Carver and Henry Ford devised a process to make a much needed rubber substitute from goldenrod during World War II. It was rather tacky and not as elastic as true rubber, but goldenrods and other native plants such as Asclepias and Chrysothamnus have rubber in sufficient quantity that may one day prove worthwhile. Tall goldenrod (Solidago altissima) had the most rubber content at 6.34 %.

Goldenrods have a unique type of inflorescence that consists of many tiny flowers that aggregate together in a flower head and form a ‘false flower’. The individual flowers are most commonly in the form of ray flowers or disk flowers. Identification of species is often done by observing the hairs on the seeds, which may be visible when the plant is still in flower. Goldenrods vary in height, with the tallest (Solidago altissima) at six feet. Some, such as sweet goldenrod (Solidago odora) have pleasant odors.

Joe pye and goldenrod Harkness Park 9-2-2018

Joe- pye weed and goldenrods blooming together at Harkness Park in Waterford, Connecticut

One of the most common goldenrods in New England is the Canada goldenrod (Solidago canadensis). It is considered alleopathic to sugar maple seedlings, producing chemicals that inhibit their growth. Habitat is disturbed areas like meadows, fields or roadsides. This is a tall plant with hairy stems and a plume flower arrangement.

goldenrods and asters in a field

Asters and goldenrods growing together in a waste area

It is associated with the goldenrod gall fly (Eurosta solidaginis) whose larva feed inside a round gall on the stem which is formed by the reaction of the plant to the larva’s saliva. You can easily find these galls when green or later in the season when stalks turn brown. The larva chew an exit hole before the plant tissue hardens up for the winter. In the spring, the adult fly will exit through this hole. Downy woodpeckers and chickadees will peck at these galls to access the larva, especially in harsh winters. Studies have shown the larger the larva inside the gall, the less likely it is to be parasitized by other insects or eaten by birds like downy woodpeckers in the winter. The goldenrod gall moth also causes a stem gall, but this is a spindle- shape rather than a ball. The caterpillar hatches from an egg laid the previous autumn and feeds its way into a stem.

goldenrod bunch gall and stem gall caused by the goldenrod Gall Fly (Eurosta solidaginis)

goldenrod bunch gall on left and stem gall on right, caused by the goldenrod gall fly (Eurosta solidaginis)

Licorice goldenrod (Solidago odora) has a licorice or anise scent and the leaves were used in a tea by the Cherokee for colds, coughs, and fevers. This plant is found in the southernmost parts of the New England states, but is absent in Maine. Found in woodlands, along roadsides, disturbed sites and old fields, the flowers have been used to make deep yellow dyes and attract beneficial insects such as lady beetles and lacewings.

White goldenrod (Solidago bicolor) is found at the edges of woodlands. It is also sometimes called ‘silverrod’ in reference to its white flowers. It is the only goldenrod with white flowers in the eastern part of the country. The stamens and pollen will give it a slightly yellow look. Sometimes the spectacular brown hooded owlet caterpillar can be found on this plant where it primarily eats the flower buds and flowers. Found more often on any goldenrods with longer flower spikes, this caterpillar is a favorite of many lepidopterists.

silver rod on the edge of woods Pamm Cooper

Silverrod at the edge of the woods.

Early goldenrod (Solidago juncea) gets its common name from its bloom time, which can be as much as a month prior to many other goldenrod species. This attractive, slender plant has a very delicate appearance and can be distinguished from other goldenrods by the lack of, or near lack of hairs on the stems and leaves. White-tailed deer, woodchucks, cottontail rabbits and livestock may feed on the plant if less desirable food is available.

Goldenrods provide a source of seeds for eastern goldfinch, tree, swamp and song sparrows as well as some migrating warblers such as the yellow- rumped warblers. Mice and other rodents eat the seeds throughout the winter and have a better time of it when seed heads are pressed down against the ground by heavy snows.

asteroid

The asteroid caterpillar

Any insects still around in late summer that have an interest in flowers may be found on goldenrods, especially pollen and nectar seekers and their predators. Some of the many insects and other arthropods that rely on goldenrods for survival are bees, wasps, butterflies, moths, flies, beetles, grasshoppers and spiders. Many of these visit for the pollen and nectar often in shorter supply as the season winds down. Migratory butterflies, especially along their shoreline routes, depend upon goldenrods for food sources as they travel south for the winter. Bloom periods are extended for at least two months as different species of goldenrods bloom in succession or coincide with each other.

gray hairstreak on goldenrod

Gray hairstreak butterfly

Black and margined blister beetles are often found on these plants in the late summer and early fall. Many beneficial insects, such as soldier beetles and assassin bugs use the flowers as either food sources or hideouts where they wait to ambush other insects. If you see a butterfly hanging upside down without moving, check and see if an ambush bug or crab spider is feeding on it. Caterpillars such as the asteroid and flower moth caterpillars, aphids, tarnished plant bugs, and many other insects feed on flowers, stems and leaves. Wasps, goldenrod and crab spiders, praying mantids, lacewings, ambush bugs, assassin bugs, spined soldier bugs and birds prey on insects that visit or live on the plants. Cucumber beetles also feed on goldenrod pollen. Some flies cause galls on stems and upper foliage as their larvae feed.

brown hooded owlet caterpillar on goldenrod from Belding September 3 2015

brown hooded owlet caterpillar on goldenrod

Chinese mantids also hang out around goldenrods, and often lay their egg masses on its stems. Look for these in the winter if heavy snows have not mashed the plants into the ground. I sometimes take a stem with the mantid egg case and stick it in my garden. The mantids usually emerge by mid- May, and they disperse quickly

mantids emerging from egg case on goldenrod stem 5-20-12

Mantid egg cases are often found on goldenrods where the adult females were hunting the year before. These are mantids just hatching

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There is a great interconnection between goldenrods and vertebrates and invertebrates, and nature reveals such things to the careful observer. If you happen upon some goldenrod, or seek it out on purpose, just a few moments of careful observation will be rewarded with a peek into the drama that is on display in a simple stand of yellow flowers.

By Pamm Cooper, UConn Home & Garden Education Center

 

Autumn brings to mind the crisp, crunching sound of leaves underfoot, meadow grasses casting a golden hue over the once green fields, and roadsides dotted with brilliant goldenrods and vibrant pink and purple asters. Not having very much fall color in my childhood backyard, oh how I loved the thought of cutting bouquets of cheerful asters for my room – that is until I discovered that those large black and yellow garden spiders were as attracted to this plant as I was! Better to just leave Mother Nature alone.

IMG_1576

Field of goldenrod. Photo by dmp, UConn

Asters used to be easy. There were over 600 species of them until molecular and morphological research in the 1990s determined there weren’t. Taxonomists pretty much divided the lot into New World and Old World species but kept them in the Asteraceae family. New World asters were put into new genus’ with tongue twisting names like Almutaster, Canadanthus, Doellingeria, Eucephalus, Eurybia, Ionactis, Oligoneuron, Oreostemma, Seriocarpus and Symphyotrichum. Now there are about 180 species in this group. Fortunately, all these plants are still referred to as asters making them easier to ask for when looking to purchase some new additions to your garden beds.

asters

Double asters on picket fence. Photo by dmp, UConn


The European Michaelmas daisy remains an aster (A. amellus). According to Dr. Allan Armitage’s Herbaceous Perennial Plants, the original species is infrequently encountered but numerous cultivars have been bred and selected for. Despite the fact that many species of plants in the aster family are native to North America, much breeding was done in England and Germany beginning in the 1890s.

In the United Kingdom, many species we commonly think of as asters are called Michaelmas daisies. The feast of St Michael and All Angels falls on September 29th as the days shorten and nights grow longer. It is written that St. Michael was an archangel who fought against Satan and protected believers during the dark nights. The celebration of this feast occurs during the asters’ bloom time, hence their nickname Michaelmas daisies. Asters are also one of the birth flowers for September.

St Michael httpswww.britannica.comtopicMichael-archangel

St. Michael from http://www.brittanica.com

The flowers of an aster are simple yet beautiful. They resemble daisies with their central yellow disk florets and their purple, pink, blue or white ray florets. The word, aster, means ‘star’ in Greek, most probably named for its rayed flowers. Pollinators flock to these plants. Native bees are continuously collecting pollen and the later blooming ones are especially sought after by both migrating and resident butterflies.

aster with bee

Aster visited by native bee. Photo by dmp, UConn.

Two types of asters most commonly found in our New England gardens are the New York aster (Symphyotrichum novi-belgii) and the New England aster (S. novae-angliae). In the wild, both species prefer sunny, moist areas but cultivated hybrids are perfectly content when planted in your average well-drained soil. Cultivars prefer being kept moderately moist during active growth periods but resent soggy soils when dormant. These unnamed asters were purchased at a garden club plant sale. The purple variety seems far more vigorous than the pink one these days.

asters in birdhs garden 2

Asters in bird house garden. Photo by dmp, UConn


 

Another interesting native aster is Eurybia divaricata, the white wood aster. The stems may reach 2 to 3 feet but they typically are a bit zig-zaggy and flop over so it looks like plants are only 18 inches high. The blossoms are small but many and the leaves are coarsely toothed and heart-shaped. White wood asters serve as a host plant for caterpillars of the pearl crescent and checkerspot butterflies.


A second great attribute of this plant is that it grows in dry shade. I have it both in my white garden under a Clethra barbinervis and 2 ‘Bridal Wreath’ spireas and also in Treebeard’s garden under a Sawara cypress mixed in with ferns, epimediums and vinca. White wood asters thrive in both and multiply in a contained manner.
White wood asters

White wood aster. Photo by dmp, UConn

For a spectacular back of the border show, the Tatarian aster (Eurybia sibirica) cannot be beat. Growing to a height of 7 to 8 feet, the plants are covered with sprays of large, bluish, daisy-like flowers starting in late September and lasting well into October. Tatarian asters will spread rapidly I quickly learned after a gardening friend gave me an innocuous looking pot full. And, they are quite drought tolerant. Staking is usually not necessary if grown on the dry side. This year because of all the rain, they have grown quite tall and might need something to hold them up.

tatarian aster w bees

Tatarian aster with bees. Photo by dmp, UConn


Dwarf asters used to be more available. These are usually crosses between two or more species. I had a cultivar called ‘White Opal’ growing in my white garden for almost a decade. It was so delightful because clear white flowers opened on 8 to 10 inch stems. It died out during a particularly warm and wet winter and I have been unable to find it for sale either online or at local garden centers.

Standard varieties of asters are generally sheared at the nursery to produce more compact plants or growth regulators are used. Then in year two in your garden, the delightful, once 14-inch high bushy plants send up stems 3 or more feet tall completely disrupting your design. Asters, for the most part, have a tendency to be somewhat loose, rangy perennials.

purple view 1

Tatarian aster, zebra grass flower heads and purple smokebush make a fine late autumn display. Photo by dmp, UConn


If you prefer more compact plants, late blooming varieties can be pinched twice, once in mid-May and again in late June. Otherwise, plan on staking the plants early in the season or position them so their sprays of blossoms have another plant or object to lean over. Pinched plants also send out side shoots so you get more blooms.

Asters grow in full sun to light shade. Fertilize them lightly each spring. Excess nutrients have been implicated in disease problems. Rapidly growing asters need to be divided every third year as the center of the clump often dies out. As with other fall blooming perennials, division is best done in the spring. Dig up the whole clump and divide the outer portion into groups of 3 to 5 stems. Discard the old woody center. Replant divisions at 18-inch intervals. Pot up extras to donate to plant sales.

As with garden phlox, it is advisable to remove spent blossoms. Seedlings are often more vigorous than parent plants and will crowd out choice selections.

The only real problem I have encountered with asters is their susceptibility to powdery mildew. Keeping them well spaced and divided to increase air circulation usually keeps this fungus problem under control. Some varieties are bred for resistance to this disease.

Asters make wonderful additions to perennial beds and borders, and are suitable for naturalizing. They will surely be as much of a star in your fall gardens as they are in mine.
Dawn P.

Viceroy butterfly on 'Miss Molly' butterfly bush September 2017

Viceroy butterfly on ‘Miss Molly’ butterfly bush

“By all these lovely tokens
September days are here,
With summer’s best of weather
And autumn’s best of cheer.”
–   Helen Hunt Jackson, September, 1830-1885

September brings a wealth of inspiration to the senses. Leaves of Virginia creeper are red already, there is the intoxicating scent of wild grapes in the pre-dawn foggy mornings, asters and goldenrods bring colorful splashes to the landscape and sunsets may fill the cooling sky with brilliant deep reds and oranges. Tree Hydrangeas, Hydrangea paniculata, had a great year, and many still have panicles of colorful flower heads. While many plants and insects are winding down to an early retirement, there is still a lot going on in the great outdoors.

Hydrangea paniculata dwarfing a visitor to Wickham Park, Manchester Pamm Cooper photo 2017

Hydrangea paniculata dwarfing a visitor to Wickham Park

It may be the time of year for oddities, now and then. For instance, there is a horse chestnut outside our office on the Storrs campus that has several flowers in full bloom this week. While many shrubs and fruit trees, like cherries and azaleas, may have a secondary bloom in the fall after rains, cool weather with a late autumn warm spell following, a chestnut blooming at this time of year is a more remarkable event. A bumblebee spent time visiting the flowers, so a second round of pollen and nectar is a bonus in that quarter.

bumblebee on horse chestnut flower 9-28-2017

Horse chestnut with visiting bumblebee – an unusual bloom for September

Red-headed crickets are a first for my gardens this September. These small crickets have a distinctive red head and thorax, iridescent black wings, and yellow legs.  At first glance, they really do not appear to be crickets because of how they move around vegetation. They also have large palps with a paddle-like end that they wave around almost constantly, giving the appearance of mini George Foremans sparring in the air before a fight. Found mostly only three feet above the ground, they have a loud trill and are usually more common south and west of Connecticut.

red headed bush cricket backyard garden 2017

Red-headed bush cricket

While visiting Kent Falls recently, I came upon a few small clumps of American spikenard. Aralia racemose, loaded with berries. Highly medicinal, this native plant is found in moist woodland areas such as along the waterfall trail at Kent Falls. Roots are sometimes used as a substitute for sarsaparilla, another Connecticut wildflower.

spikenard Kent Falls 9-11-17

American spikenard berries ripen in September

Many migrating butterflies like monarchs and American Ladies are on the move now and may be found on late season flowers like butterfly bush, zinnias, Tithonia, Lantana, cohosh, goldenrod, asters and many other flowers. In annual plantings where I work, honey bees are especially abundant on Salvia guaranitica  ‘ Black and Blue ’  right now.  And while many butterflies and bees can be found on various butterfly bush cultivars, the hands on favorite seems to be the cultivar ” Miss Molly” which has deep red/pink, richly scented flowers that attract hummingbirds, flower beetles, fly pollinators, people and bees galore. This is a great addition to a pollinator or butterfly garden. Other late season bloomers for our native insects and butterflies are black cohosh and Eupatorium  rugosum, (chocolate Joe-Pye weed), as well as asters and goldenrods.

American lady on Tithonia sunflower

American Lady on Tithonia sunflower

Black and blue salvia

‘Black and Blue’ salvia is great for attracting hummingbirds and honey bees

Snapping turtles are hatching now.  The other day while mowing fairways, I spotted long dew tracks and there at the end were two little snapper hatchlings. Very soft upon hatching, they are often heron chow, and these little turtles will travel long distances to find a good habitat.

newly hatched snapping turtle 9-25-2017 Pamm Cooper photo

Newly hatched snapping turtle

Every day at my house, we engage in a “Where is Waldo?” type hunt in the backyard gardens. What we are looking for are the tiny gray tree frogs that are hanging out on certain plants during the day. Snapping up any insects that get too close, these guys are a lot of fun to watch and look for. Most of ones we are finding are green, and are slightly larger than a thumbnail right now.  It gives us all some free entertainment before the leaves fall and we move on to- raking leaves…

two thumbnail size gray tree frogs Pamm Cooper photo

Two tiny gray tree frogs in my garden

Katydids, crickets and sometimes tree frogs are making a racket at night. Although really not unpleasant, to me, they are loud. But more enjoyable to listen to than the neighbor’s barking dog…I found a katydid eating a hyssop flower recently, but who cares about that this late in the year?

katydid eating hyssop flowers in September

katydid eating hyssop flwer

Bees are having their last hurrah now as the blooming season winds down. While native goldenrods and asters are important food sources of food for late season bees and wasps, there are many garden plants that are important nectar and pollen sources as well. In my own garden, I have two hyssops- anise and blue giant hyssop. There were bumblebees and honeybees that went on both, but there were small bees that preferred only the anise hyssop. These bees were very noisy, and hovered near flowers before landing, behaving like hover flies. Most likely these bees were in the Megachilid genera- the leaf-cutting bees. Abdominal hairs collect the pollen in these species and may take on the brilliant colors of pollen from the flowers they visit.

Megachilid leaf cutting bee on aster Belding September 2017

Megachile family leaf-cutting bee on aster

As the season winds down, there are still some caterpillars to be found, like the beloved wooly bears and other tiger moth cats like the yellow bear. A spotted Apotelodes was a good find. A robust, densely hairy caterpillar, this large fellow is notable for three sets of long hairs called “pencils” along the dorsum, and for its equally conspicuous red feet, making it look like it is wearing five pairs of little red shoes.

spotted apatelodes on honeysuckle Cohen Woodland field 9-12-2017 Pamm Cooper photo

Spotted Apatelodes caterpillar showing its little red feet

And just for fun, next year consider planting a candy corn vine, Manettia inflate, on a small trellis.  An annual vine, flowers last well into the fall before the first killing frost. This South American native has tubular flowers that resemble candy corn, and they are a favorite of the hummingbirds (and myself!) in my backyard.

candy corn vine an annual fun plant Pamm Cooper photo

Candy corn vine

 

Pamm Cooper