There’s Nothing Wrong With Those Leaves, They’re Just Dying.

One of the best parts about going to plant sales and setting up a booth is that you get to hear everyone’s story about their favorite plants that you may or may not be selling.  Seeing people enthusiastic to learn and share plant knowledge refills my inner reservoir of hope.   We participated in the Hall County Master Gardener’s Fall Expo last weekend and talked to some wonderful people (many of whom were Hall Co. Master Gardeners, y’all were awesome!) and sold a bunch of plants.  One exchange in particular made me incredibly happy because I finally heard someone express the concept I’ve been trying to convey to anyone that will listen for years:  Leaves on a perennial plant (especially in fall ) are expendable and don not necessarily reflect the overall health of the plant.

Agastache leaves showing some yellowing as they break down.

I was talking to a couple as they browsed our plants, and as the wife decided she would like a Giant Hyssop (Agastache scrophularifolia) she picked up two pots and started comparing the plants in them.  She asked her husband, “Which one?” He responded that they looked about the same.  She expressed concern about the yellowing leaves on one of the plants, but it had more stems, so she kind of wanted it more. He turned to me and asked “It’s perennial, right?” I said that it was with a nod.  He said “Well, then you’re buying the roots. Those leaves are going to be gone in a few weeks anyway.”  I think I just found my new best friend.  I’m pretty sure I saw the wife roll her eyes and then select the plant with 2 stems.

Magnolia macrophylla with some leaves that have seen better days, but quite healthy roots

Leaves on a perennial plant go through an annual life cycle that eventually ends with them shutting down and dying.  This is known as ‘leaf senescence’ and most people know it more commonly as “when the leaves change color in Autumn.”  This cycle was summed up incredibly well in a paper about the molecular causes of leaf senescence that I came across:

“Leaves initiate their life as leaf primodia. During their development and growth, they become photosynthetically competent and accumulate nutrients. Leaves then enter the senescence stage, followed by their death. Leaf senescence partly involves the process of ‘wear and tear’ during aging, but mostly is a tightly regulated process with a crucial biological purpose.”    – http://jcs.biologists.org/content/126/21/4823

Leaves are formed, perform their function of collecting solar energy to build roots, stems, more leaves and flowers, and then are systematically dismantled and their components are resorbed and redistributed to other parts of the plant.  The remaining framework is then dropped to the soil, most likely to be reabsorbed by the roots after passing through the soil food web.

In this context, looking for the leaves to be green and healthy on a plant in October seems a bit absurd.  Plants that bloom in spring usually shut down in the summer heat, and the ones that bloom in fall are sending all their resources to make flowers and then seeds before a frost comes along.  Another quote from the aforementioned paper again sums it up well:

“The blooming of spring flowers occurs through the utilization of nutrients that have been relocated from senescing autumn leaves. Thus, senescence and death in leaves are active developmental strategies that crucially contribute to the fitness and survival of a plant.”  –ibid

Just look at this beautiful Georgia Aster bloom:

Now take a look at the leaves closer to the base of the stem:

Not nearly as aesthetically appealing as the flower, but part of a totally necessary and natural process on a healthy plant.

Fall is the best time to plant perennials, so now is the time to shop at one of the many plant sales going on in the next few weeks.  If you see some less than perfect leaves, don’t worry. They won’t be there much longer. They too shall pass, and in doing so enable the roots to survive the winter.


Milkweed for Monarchs….and everyone else!

The recent push to plant Milkweed for Monarchs is a welcome development in the gardening community.  Monarchs are dependent on Milkweed (Asclepias spp.) for their survival, as it is the only food their caterpillars can eat.  But it’s not just for Monarchs! LOTS of pollinators visit the flowers to drink the nectar.  I took my camera out to several of our patches of Orange Milkweed (Asclepias tuberosa) yesterday to document a smapling of the variety of insects I see on the flowers.

One of the common names of Asclepias tuberosa is ‘Butterflyweed’ so one would expect to see butterflies.  This female Tiger Swallowtail (Papilio glaucus) is dipping her long proboscis into the nectar rich base of the flower in order to drink it up.  It’s like a built in straw.

A close cousin, the Zebra Swallowtail (Eurytides marcellus) also feeds on the nectar. Much like the Monarch Zebra Swallowtail caterpillars can only feed on the leaves of the plants in a single genus, Asimina, or Paw Paws.

This Common Buckeye (Junonia coenia) was looking a little tattered, as it was probably approaching the end of it’s ~2 week long adult life.  It was still sipping nectar as it rested on the flowers.

Bees also love the nectar from this plant.  Here a Green Sweat Bee (Agapostemon spp.) perches it’s tiny body atop the flower as it sips nectar from inside. It’s just one of the hundreds of species of native bees here in Georgia.

Another Native bee, possibly a Leafcutter bee (I’m not an entomologist), feeding on nectar.

Another possible leafcutter bee: the whitish mat of hairs on the underside of it’s abdomen are used for collecting pollen.  Look closely to the right of the bee and you’ll see an ant sipping nectar as well.

Speaking of Ants, this Fire Ant also found it’s way up the 3 foot tall stalks for a sugary meal. Ants can be pollinators too, and they are responsible for dispersing the seeds of many spring blooming wildflowers such as Trillium and Bloodroot.

This Great Golden Digger Wasp (Sphex ichneumoneus) feeds on nectar as an adult, but like most wasps it hatched from an egg laid on another insect and fully consumed it before the metamorphosis into it’s current winged form.  Golden Digger Wasps are predators to Grasshoppers, Katydids and Crickets.

This Yellow Jacket adult enjoys sugary nectar, but its larvae need a more protein rich diet, which the adults supply by hunting other insects (many of which are agricultural pests).  Wasps are much maligned by humans, but without their predatory behavior we would be literally drowning in bugs and our crops would be decimated.

And finally, not everyone is there for the nectar! This is one of several clever lizards I’ve seen recently near blooming flowers lying in wait for some distracted pollinator to drift too close…..

Milkweed is for Monarchs, but after they have migrated north it’s for butterflies, moths, bees, wasps, ants, beetles, aphids, and even lizards.


Podcasts for the Plant Enthusiast

Podcasts have become a bit of an obsession for me in the past 12 months.  I spend long hours alone in the greenhouse sowing seed trays, dividing crowns, and potting up plants.  I used to listen to music with an occasional audiobook to keep my sanity, but even 10,000 songs on shuffle got old eventually.  In the course of looking for something to entertain and, hopefully, enrich my mind I have stumbled upon a number of podcasts that are now a part of my daily routine.  If you are already familiar with podcasts and how to get them, feel free to skip to the bullet points for my favorites.  If you haven’t ventured into the world of podcasts just yet a short introduction follows.

First: what is a podcast?  It’s a pre-recorded audio production (‘radio show’) that you download or stream and listen to on your phone/computer/internet-connected device.  Most of the shows NPR produces are also available as podcasts, so that should give you a basic idea of the format.  Unlike NPR or radio, pretty much anyone can make a podcast, which means there is a lot a variability and people trying new things.  The upside is that increased access lends itself to a wide variety of shows about specialized and often esoteric subject matter (like native plants).  The only downside I’ve encountered is that sometimes the quality can be lacking for the more specialized subjects (like native plants), but better shows are coming out all the time. Fortunately, most podcasts are completely free to the listener, and there are ratings and reviews that can guide you to good quality productions.

Now, where to get these podcasts?  If you are into Apple products and/or use iTunes, that will be your best bet.  They did invent the podcast, so I’ll give them credit for that and say that most podcasts are available there first.  If you don’t use iTunes, then there are a few other ways to listen.  There are a number of apps, often referred to as ‘podcatchers’ available for free in whatever app store you use.  Download the app, open it up and start browsing for episodes.  I am using Podcast Republic at the moment and I would say it works quite well for me.  The advantage of installing the app is that you can download the episodes for offline listening.  This is especially great for listening in the car or in areas that have poor cell/wi-fi coverage (like the greenhouse) where streaming is not an option.  If you aren’t into the apps and downloads then you can always just listen through your regular web browser on whatever device you use to internet.

Now that the podcast basics are covered, here are the shows that I enjoy and recommend:

  • The Native Plant Podcast – This is a recent find, but has quickly become one of my favorites. I think I might have met the hosts, Mike and John, at the Cullowhee Native Plant Conference back in 2013.  They are both entertaining, knowledgeable guys that run businesses growing and installing native plants in Tennessee and Virginia respectively.  They bring on a guest each week to interview and discuss various aspects of plants, ecology, horticulture, and the nursery industry.  They also end each show by telling short stories about their dogs and having a toast with their guest, usually involving dark beers.  Native plants, dogs and beers: I’m sold.   This episode with Dr. Doug Tallamy is a great introduction to him and his work, and also has some good new info for those already familiar with him.  A quote from this episode with Dale Hendricks that  made me feel better about some of my nursery failures was:“You find a professional grower and you find a person that, for better or for worse, has killed a lot of plants.” It also has a lot of more positive talk about biochar, his role in founding North Creek Nurseries, his new found interest in permaculture, and Paw paws.

 

  • Plants: From Roots to Riches was a BBC radio program, and is now available as a podcast. It’s a good overview of the history of botanical studies, the people that made went exploring all over the globe and the plants they found, collected, studied and grew.  The host, Prof. Kathy Willis is the director of science at Kew Gardens, one of the oldest botanical gardens in the world and a key institution in the development of botany as a proper science.  She enlists her numerous colleagues at Kew and abroad to explain how empire, industry, and agriculture fueled the need for botanical expertise. The episodes are pretty short (about 14 min. each), so the series of 25 went pretty quickly for me.  It’s a very well produced, accessible, narrative of the past 300 years and the revolutions in scientific studies that have changed the ways we view and interact with plants.

 

 

  • In Our Time – Now, we’re getting away from strictly plant based podcasts, but this one has something for everyone.  It’s from the BBC, and the host Melvyn Bragg moderates a panel of experts on a given topic each week and they discuss the history of said topic.  It is often a work of art, a scientific theory or invention, or a social phenomenon.  This episode about Photosynthesis really helped me to visualize the inner workings of plant cells as they make their make their food and breathe.  This episode about the structure of the cell is also fascinating, as are any of the many episodes about astronomy, geology, physics and paleontology. Tons of episodes all chock full of people that have devoted their lives to studying a subject explaining it to a genial British man in fairly simple terms.  You’re bound to learn something new.

Those are all for the plant enthusiast, but others that I regularly enjoy and recommend are: This American Life,  Nerdist, WTF with Marc Maron, Talking Simpsons, You Must Remember This, Radiolab, Invisibilia, Longform, and Snap Judgement.

Happy listening, and if you know of any other good (native) plant-related podcasts recommend it in the comments!


Sweetshrub: 100 Million Years of Blooms

The flowers of Sweetshrub (Calycanthus floridus) are in full bloom right now.   They are a deep maroon color that contrasts nicely with the bright, glossy green of the foliage.  Some plants have more fragrant blooms than others, but if you can find an aromatic one do yourself a favor and take in the smell.  Kind of like strawberries mixed with bananas and a little cinnamon or clove tossed in: there are not many fragrances like it.  The overripe fruits of Sweetshrub’s cousin, Paw paw (Asimina triloba) are the closest scent that comes to mind.  Sweetshrub flowers are unique in appearance as well with their spidery tepals wrapped around a central cluster of anthers. They look like they haven’t quite opened yet.   The color, structure and smell of these flowers differ from most of the flowers that are familiar to us today because they are the results of adaptive strategies first developed over 100 million years ago.

Fossils from Brazil that date to the Cretaceous period (115 million years ago) have shown us the form of an ancestor of Sweetshrub named Araripia.  The fossil “comprises flowers, buds, and leaves, and exhibits features that suggest that “among the Calycanthaceae, especially flowers of Calycanthus are most similar to the flower of Araripia”  The Earth was a much different place 115 MYA to say the least: Only two massive continents, Gondwana and Laurasia, existed and the climate was much warmer and humid.  Dinosaurs roamed the land and insects of all sizes occupied every niche in the dense tropical forests that covered the entire planet.  Plants and insects were just beginning to respond to one another’s adaptive strategies.  These responses were the first steps on a co-evolutionary path that would lead to very complex and specialized forms and life patterns on both sides of the aisle.  Sweetshrub is a living relic from a time before bees when plants were just “learning” that insects could be used to facilitate cross pollination if they are given a little incentive.

This cutaway picture of a Calycanthus bloom shows the minimal differentiation of flower parts as one passes from outer to inner bloom.  Instead of two separate parts, sepals and petals, there are tepals (a half-way-between-the-two structure more commonly found in monocots) surrounding and enclosing the anthers and ovary.  The pollen producing anthers are very similar in their shape and arrangement to the tepals and very simple in form.  The size is really the only variant in the form of the floral parts; There isn’t a lot of specialization.  There are no nectar bearing parts to appeal to bees and butterflies because this flower form evolved before they did.  Beetles were the most likely insects to transfer pollen between flowers as they ate it, so they are meant to appeal to beetles.

Attracting a beetle to a flower is not the same as attracting a bee or butterfly.  First, there are the visual cues.  Beetles, like moths, are attracted to bright white flowers, such as a Magnolia flower (also ancient and beetle pollinated), that reflects light well, especially at night.  Some beetles are also attracted to deep reddish-brown colors, as several other plants known to be pollinated by flies and carrion feeding beetles such as Pawpaw (Asimina spp.), Carrion Flowers (Stapelia spp.) and Pipevine (Aristilochia spp.) have adopted a similar color scheme;  Possibly to mimic wounded or rotting flesh.  Second, there are olfactory cues.  Many beetles evolved to feed upon the carcasses of other animals or their excrement.  An appealing odor to a beetle is not necessarily the sweet smells that we humans most often associate with flowers or fruits.  A spicy, earthy aroma that suggests some sort of decay is more likely to attract a bunch of beetles. Third, there is the form of the flower itself.  Very simple, no complicated pollen sacs or parts that mimic female insects like orchids; no separate disk and ray flowers like asters, just the tepals in a semi-enclosed arrangement around the pollen bearing anthers and ovary.  Beetles aren’t there for the sweet carbohydrate nectar, they just want the protein rich pollen.  In the process of eating, they get covered in pollen grains that will be transferred to the next flower they feast upon.  Mass appeal with vaguely appetizing aromas and easily accessible flowers were the beginnings of plant-pollinator relationships that grew more specific and specialized over the ensuing 115 million years to give us the biodiversity we see today.

Sweetshrub has been a popular cultivated shrub in the south since Europeans arrived, and continues to do well in the nursery trade to this day.  I don’t think that many people, even among those that plant it and enjoy it, are aware of its ancient lineage.

 

Post Script/Cultivation Note:

The seeds of Sweetshrub are large, easy to collect and fun to grow. They also demonstrate a unique and probably ancient strategy of having no energy reserves stored in the seed.  It’s just the seed leaves (cotelydons) wound tightly in a spiral inside the seed coat waiting to unfurl and capture solar energy.

The relatively huge leaves quickly make up for the lack of stored reserves and the true leaves and stem shoot up through the middle of them.


Caterpillar Host Plants: Harvesting Solar Energy for Wildlife

Plants feed wildlife. Plants feed nearly all life as we know it.  They are the base of the food web and produced much of the oxygen in the atmosphere:  Calories to consume and the fuel to burn them.  Even those creatures that consume other animals are dependent upon plants for their survival.  The solar energy that plants convert to sugars and the minerals that they mine from the soil slowly make their way up the “food chain” to even the most carnivorous apex predators via the bodies of their herbivorous prey.   The somewhat outdated concept of the “food chain” can still help to visualize the process of nutrients and energy cycling through natural communities.  These days it is most often referred to as a “food web” and the following graphic is a simplified representation of how it functions with some familiar examples.

food_web

(There should be more arrows going all over the place, a ‘web’ if you will, but like I said, this is simplified to highlight the cyclical nature of the whole process.)

The main points of this graphic I want to focus on are 1) Energy comes from the sun.  2) That energy is harnessed and stored as carbohydrates by plants.  3) The rest of the system depends upon harvesting that stored energy.  Everything else is standing on that foundation of plants

As omnivores, humans have the ability to derive our energy from many sources, and in fact need a varied diet to acquire all of the nutrients necessary for our bodies to function.  It allows us to occupy nearly any area on the planet, but other creatures are not so easily adaptable to new foods and environments.  Survival strategies are often dependent on the seasonal abundance of plant resources with periods of migration or hibernation to cope with food scarcity.  Many insects have evolved to become specialists at feeding on certain types of plants in response to the annual growth cycles in temperate climates.  Typically, an egg is laid on or in a preferred food source, a larva emerges and feeds on that food source until it consumes enough energy to pupate into a winged adult.  The adult then flies off to find a mate, locate another larval food source, lay egg(s), and repeat, if possible, until they die.  Aphids, Wasps, Bees, Moths, Butterflies, Flies, and Beetles all follow this same basic life cycle.

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Black Swallowtail laying eggs on Meadow Parsnip (Thaspium trifolatum)

Butterflies and Moths, collectively known as Lepidoptera, have adapted specialized strategies to feed on plants and mitigate the effects of their defenses in an evolutionary tango over the past 60-100 million years. Through the process of evolution and adaptation the insect’s fate has been inextricably tied to the fate of the plants they consume.  Lepidopteran larvae, commonly referred to as: caterpillars, grubs, tentworms, silkworms, inchworms, armyworms, etc. are a crucial first step in transferring the sun’s energy throughout the ecosystem.  A feature of their specialized feeding behavior is that they have become much more efficient at converting the plant material into proteins with which they build their bodies.  Those proteins are the main food source for many of the creatures that occupy the next trophic level up the pyramid.

Enigmogramma basigera (Pink-washed Looper Moth)

Freshly emerged Pink-Washed Looper Moth (Enigmogramma basigera) and it’s cocoon on a Cardinal Flower (Lobelia cardinalis). Many of it’s larval siblings were dinner for baby birds.

One of my favorite sources for information on butterflies, moths and caterpillars is BAMONA (Butterflies and Moths of North America), a website/database operated by the Butterfly and Moth Information Network.  It has tons of information and resources for anyone looking to learn more or contribute their knowledge and sightings of Lepidopterans.  I spent a little while browsing their database of species and compiled the following list of common names for Butterflies and Moths. See if you can spot the pattern:

“Elder Shoot Borer Moth, Maple Leaftier, Small Aspen Leaftier Moth, Black-headed Birch Leaffolder Moth, Oak Leaftier Moth, Poplar Carpenterworm Moth, Birch Tubemaker Moth, Pecan Leaf Casebearer Moth, Alder Tubemaker Moth, Birch Dagger Moth, Cottonwood Dagger Moth, Tupelo Leaffolder, Fringe-Tree Sallow, Knapweed Root-borer Moth, Poison Hemlock Moth, Virginia Creeper Borer Moth, Fall Clematis Clearwing Borer, Seagrape Spanworm Moth, Walnut sphinx, Poplar Catkin Moth, Yellow Birch Leaffolder Moth, Consular oakworm moth, Oslar’s oakworm moth, Peigler’s oakworm moth, Orange-tipped oakworm moth, Spiny oakworm moth, Pink-striped oakworm moth, Orange-striped oakworm moth, Chestnut Crescent, Live Oak Antiblemma, Oblong Sedge Borer Moth, Large Boxelder Leafroller Moth, Spring Spruce Needle Moth, Fall Spruce Needle Moth, Cherry Shoot Borer, Hickory Leafroller Moth, Hackberry Emperor, Ten-spotted Honeysuckle Moth, Wavy Chestnut Moth”

(These are just a sampling of the species whose Latin names begin with the letter ‘A’!)

The pattern to which I was referring is that the plant that the larva feeds upon is right there in the adult’s name.  Many even tell you the plant part they consume: Leafroller, Shoot Borer, Root Borer, Poplar Catkin, Spruce Needle, etc.   Being a specialist at consuming such specific plants and plant parts confers the advantage of less competition for food resources, but it is a double edged sword.  If that particular plant or part of the plant is not available then the caterpillars cannot survive.   This is where you, the human, enter the picture.  Many of the native plants that were interwoven into the landscape and served their purpose as a larval food source for millennia have been marginalized or removed altogether.  First, agriculture, next urbanization and development, and then landscapers all took turns removing the native smorgasbord and replacing it with foreign, undigestible plants.  Whereas a human might view a Chinese Cherry tree ringed with a border of Monkeygrass surrounded by a freshly mown lawn as a tidy, beautiful landscape, a butterfly looking for a place to feed and nurture her young might see a desert or a wasteland devoid of food.  That same human would probably derive a very similar aesthetic pleasure from an American Cherry Tree ringed with sedges and surrounded by native bunchgrasses, and over 500 species of Lepidoptera would see food and a nursery for the next generation.

Spring is nearly upon us.  That time of year when everyone briefly turns their attention to beautifying their yards before it gets too hot.  Beware the big box stores and their clone armies of gold medal winning plants injected with systemic insecticides.  “Pest Free” is another way of saying “Useless to Wildlife.”  Resist the impulse buy in the garden center.  Do your research and find some plants that will satisfy your aesthetic wants AND wildlife nutritional needs.

blackswallowtails

Black Swallowtail caterpillars on Meadow Parsnip (Thaspium trifoliatum). The plants responded with lush new growth a week later.

 

Postscript:

In the course of researching moths for this article I stumbled upon an account of a moth with a truly unique larval food source: The Gopher Tortoise Moth (Ceratophaga vicinella).  Based on the naming conventions described above what would you guess that Gopher Tortoise Moth caterpillars eat?  If you guessed Gopher Tortoise Shells you would be correct!  More specifically they consume the solid keratin that binds the many plates of a gopher tortoise shell together.  Keratin is the same protein found in your hair and fingernails and other natural fibers such as wool.  The ability to digest and derive sustenance from keratin is shared by a close cousin of the Gopher Tortoise Moth: the common Clothes Moth that loves to eat (you guessed it!) wool clothing and rugs.  The amazing part of this relationship to me is that there used to be such a surplus of Gopher Tortoise shells laying around that their abundance encouraged an entire new species to branch off and specialize in consuming only tortoise shell keratin.  Sadly, this strategy has proven to be risky with the decline of Gopher Tortoises, which is a direct result of the decline of the Longleaf Pine-Wiregrass ecosystem (and its seasonal fires) on which they are dependent.   There are hundreds of other animals and insects that depend on Gopher Tortoises and their burrows in some form to survive, and none of them are doing well.  Bring back the Longleaf!

 


Summer Blooms

Despite (or because of) the heat and intense thunderstorms our plants are making some beautiful blooms:

IMG_6860

Cedarglade St. John’s Wort (Hypericum frondosum) is a favorite of the bees, and you can see why: pollen for everyone!

IMG_6864

Widow’s Frill (Silene stellata) is indeed frilly, and as the species name suggests, star-like.

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Cardinal Flower (Lobelia cardinalis) is always gorgeous, and a favorite of the hummingbirds.

IMG_6870

Speaking of hummingbirds, this is the result of their work pollinating another plant, Coral Honeysuckle (Lonicera sempervirens).  This is the first time I’ve ever seen a seed pod form on one of these and wouldn’t you know it’s bright red just like the flower.

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Purple Coneflower (Echinacea purpurea) providing both food and shelter from afternoon showers for this bumblebee.

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And finally, Blazing Star (Liatris spicata).  Keep these beauties in mind when planning you fall plantings.

 


Top Ten Native Plants for a Diverse and Beautiful Yard

This article originally appeared in the Wylde Center Fall 2015 Newsletter.

A short list cannot begin to describe the immense diversity and variation in the plant species and communities that evolved in what is now Georgia, USA. This list is just an attempt to get you to think about the plants that are in your yard and garden, where they came from, and what purpose(s) they serve. Landscaping can be beautiful AND provide food and shelter for wildlife.

In selecting these plants my criteria included: Native to Georgia, Number of caterpillar species hosted, Production of fruits/nuts for birds (and humans), Abundant flowers for pollinators (and humans), and cover/shelter for birds. The number of caterpillar species hosted is doubly important: Some lucky caterpillars get to grow up to be butterflies and moths that help pollinate flowers, but the vast majority of them are destined to be eaten by birds and other animals. Baby birds need large amounts of fat and protein to develop their brains and bodies just like baby humans, but unlike humans, birds cannot deliver these nutrients via milk. It takes lots and lots of caterpillars to raise a healthy bird to maturity. Each selection starts with a whole Genus of plants, and then narrows to one or two species that are endemic to the Piedmont. There are two reasons for this structure: The numbers for caterpillar species hosted* are expressed by genus, and if conditions in your yard will not support my selections then you can research the other members of the genus. The wide diversity of plants in the Southeast almost guarantees that there are other species in the genus that will find your yard delightful. Mindful selection of native plants for your yard helps to reunite a fragmented landscape into a larger community, and gives us all a sense of place in the land that we call home.

*All numbers cited for caterpillar species hosted come from Dr. Douglas Tallamy’s invaluable research that can be found on his website at http://www.bringingnaturehome.net/

Wild Cherry – Prunus spp. Prunus_angustifolium_01
Wild Cherry, Chokecherry, Wild Plum, Black Cherry and Laurel Cherry are some of the common names given to the native members of this genus. It also includes the cultivars that give us our plums, cherries, almonds, apricots, and peaches. The native Prunus species host a whopping 429 different species of caterpillars! In addition to the caterpillar smorgasbord, the fruits are also an important food source for birds. Chickasaw Plum (Prunus angustifolia) is a small tree (15 to 25 feet at maturity) that has glossy dark green leaves and reddish-brown bark. Clusters of small white flowers bloom in early spring, which provides much-needed nectar for emerging native bees. The small ½” reddish-orange fruits ripen in the late summer. The fruits are usually a bit tart to our modern tastes, but have a long history as a food source for Native Americans, and were later used to make jams, jellies, and wine by colonists. If you have the space Black Cherry (Prunus serotina) is a full size tree (up to 100 feet) with the same early blooming white flowers. The fruits are small, but abundant, and also have a long history of use in jams and pies, and as a flavoring in many foods and beverages.

Blueberry – Vaccinium spp.

vaccinium
Blueberries should be very familiar to anyone that has spent even a single summer in Georgia. The Vaccinium genus also contains the species commonly known as: Bilberry, Huckleberry, Cranberry, Whortleberry, and Lignonberry. Its members host 286 species of caterpillar in addition to making those delicious berries. The creamy white bell-shaped flowers bloom early in the season providing nectar for bees, and have their own native specialist pollinator, the Southeastern Blueberry Bee, that utilizes “buzz pollination” to efficiently transfer pollen and increase berry production. The Southern ‘Rabbiteye’ Blueberry (Vaccinium virgatum or V. ashei) has numerous named cultivars selected to produce tasty berries if you can beat the birds. It does better in the Southeastern climate than the Highbush Blueberry (Vaccinium corymbosum), which is a more northerly native, and also has numerous named cultivars. Cultivars are all essentially clones, so make sure to plant at least two different ones for good cross pollination and berry set. If you want a true native try the amusingly named Farkleberry (Vaccinium arborescens), for a large shrub with evergreen leaves and smaller, tart berries that birds will still readily eat.

Joe Pye Weed – Eutrochium/Eupatorium spp.**
Eupatorium2
Joe Pye Weed (Eutrochium fistulosum) is already a popular garden plant, especially with butterfly enthusiasts. It grows up to ten feet tall in ideal conditions (part shade, moist soils) and produces large rounded clusters of hundreds of tiny pink flowers. Every shape and size of pollinator will be on this plant at the height of its bloom in late summer. Another member of this genus that also attracts numerous and diverse pollinators is Boneset (Eupatorium perfoliatum). It has a long history of medicinal use by Native Americans and later by colonists. Boneset is easily recognized by its large, fuzzy perfoliate leaves. The opposite pairs are joined at the bases, and the stem appears to perforate them. Rounded clusters of white to pinkish blooms top the stalks in late summer. Eupatorium hosts 40 species of caterpillars, provide abundant nectar for adult butterflies, and follow through with lots of seeds for songbirds.

**Thanks to DNA sequencing all of the plants that used to be in the Eupatorium genus are constantly being shuffled around a few genera, so I am treating these two interchangeably.

Sedges – Carex spp.
Carex
Sedges are very similar to grasses, and are in fact close cousins of the grass family. They tend to be shorter at maturity, have broader leaves, and prefer partly shady moist areas, whereas grasses tend to prefer drier, sunnier habitats. Sedges are very well suited for border plantings at the edges of walkways, flower beds, and around the bases of trees. Anywhere that one might consider planting the dreaded invasive Monkeygrass (Liriope spp.) is a spot that would be much better off with a group of sedges. Broadleaf Sedge (Carex platyphylla) has attractive silvery green leaves that form dense clumps 8-10” tall and put up spiky flower heads that develop into seeds for songbirds. Blue Wood Sedge (Carex flaccosperma) has blue-green leaves, is semi-evergreen, and blooms in early spring. Carex hosts 36 caterpillar species in stark contrast to Liriope’s zero.

(NATIVE) Honeysuckle – Lonicera spp.

Lonicera sempervirens
The sweet smelling and tasting Honeysuckle with the creamy white flowers that is most often associated with that word is actually highly invasive and originally native to Asia. Lonicera japonica was spread all over the world in the 19th century and is now on every continent except Antarctica. Please do not propagate this plant, despite the fact that many nurseries continue to sell it. Scarlet Honeysuckle (Lonicera sempervirens) is native to this country, and is a tree-safe vine that produces clusters of brilliant red tubular flowers in mid-spring. These flowers are an important nectar source for our resident and migratory hummingbirds. The foliage is semi-evergreen, and the plant roots easily at the nodes making it easy to grow and multiply. It can be trained onto a trellis or fence into a very attractive, cascading mass of dark green leaves and bright red blooms. Yellow Honeysuckle (Lonicera flava) is another US Native that is essentially the same as Scarlet Honeysuckle in all respects except flower color. Its yellow tubular flowers are also attractive to hummingbirds. The native Lonicera plants host 33 species of caterpillars.

Goldenrod – Solidago spp.

Solidago
Goldenrod often gets a bad reputation by association. It blooms the same time as Ragweed, and frequently gets blamed by allergy sufferers as the cause of their congestion. Goldenrods are pollinated by insects, and as such do not release clouds of pollen into the air like Ragweed. The beautiful yellow flowers are a favorite of many pollinators when they bloom in late summer as most other flowers have faded. In addition to beautiful, nectar bearing flowers goldenrods host 112 species of caterpillars. Showy Goldenrod (Solidago erecta) is a low-growing set of leaves for most of the year until it sprouts a 3-4 foot tall stem in late summer that is covered in hundreds of tiny yellow flowers. The small seeds that follow the blooms are readily consumed by birds. Wrinkleleaf Goldenrod (Solidago rugosa) is a slowly spreading, rhizomatous, colony-forming plant that has deep green leaves with toothed margins. The low-growing rosettes of leaves put up stalks lined with small yellow flowers in late summer that are followed by abundant seeds.

Hawthorn – Crataegus spp.

Crataegus
Hawthorns are large, thicket forming, woody shrubs in the Rose family. As with roses, they have beautiful flowers and large thorns. A thorny hedge is a great way to deter a nosy neighbor, and it makes ideal cover for nesting birds. Hawthorns flower in early spring, which makes them another important nectar and pollen source for native bees, they produce edible fruits, and host an impressive 150 different species of caterpillars. Yellow Hawthorn (Crataegus flava) is a drought tolerant small tree/ large shrub with clusters of bright white flowers in early Spring, yellow fruits in Summer, and beautiful foliage in Autumn. Parsley Leaf Hawthorn (Crataegus marshalii) is a multi-stemmed upright shrub with small, deeply incised leaves that resemble parsley leaves. Small white flowers are followed by bright red fruits that persist on the plant to become winter bird forage. It does well in average to dry soils and part shade.

Arrowwood – Viburnum spp.
Viburnum
Viburnums are very popular with landscapers and developers. Low water needs, tolerant of many soils, attractive glossy foliage, beautiful flowers, autumn colors: They knock it out of the park. Unfortunately, many of the varieties that are in the nursery trade are either from Asia, or have been hybridized with Asian species. This has made for some very interesting looking cultivars, but there is scant research on whether or not the 97 species of caterpillars that feed on native Viburnum leaves can fully utilize these non-native plants. Best to err on the side of caution on behalf of the caterpillars and plant a native that will also produce viable seeds for the birds to spread around. Mapleleaf Viburnum (Viburnum acerfolium) is a great shrub to grow in the filtered shade of a large tree. It spouts multiple 3-5 foot tall stems lined with large opposite pairs of deep green leaves that are easily mistaken for Maple leaves. Rounded clusters of small white flowers bloom through the spring, and are followed by pea-sized blue-black fruits that birds will devour just as quickly as blueberries. The leaves put on a spectacular color show in autumn shifting through yellow, orange, red and then purplish hues before they drop for the winter. A larger specimen is Rusty Blackhaw (Viburnum rufidulum) which is a thicket forming large shrub/small tree that grows 10-20 feet tall. The young leaves are covered in fine red hairs that give them a “rusty” appearance, and they also turn brilliant colors in the fall. It does best in average to dry soils and full sun to part shade.

Asters – Symphyotrichium spp.

Symphyotrichum
Asters are one of the largest plant families encompassing over 1600 genera of closely related plants with very similar looking flowers including Sunflowers, Daisies, Coneflower, Black Eyed Susan, and many, many more. The members of the Symphyotrichium genus tend to be named “(Person/Place/Adjective) Aster.” Georgia Aster (Symphyotrichium georgianum) should be our state flower. It is a drought tolerant rosette of low-growing leaves for most of the year, but starting in September a 3-4 foot tall branching stalk of blooms emerges. The abundant 2” flowers have deep purple petals with purplish-white centers that often continue to bloom through October into November making it a great source of late season nectar and pollen. Another late bloomer that is also inconspicuous until it flowers is Calico Aster (Symphyotrichium lateriflorum). Its 2-4 foot tall bloom stalk is covered with hundreds of small white flowers with yellow centers that fade to brown as they age. The blooms continue to emerge through November or until they are killed back by frost.
(more…)


Best Pics of 2015

As an ode to the ‘manual’ mode on my camera I thought I’d share my favorite plant-related pictures that I took in the past year.

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‘Monarch Oviposit’

This image finally explained to me how their eggs get on the underside of the leaf as they are perched on top of it.

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‘Ladybug Larva Devouring an Oleander Aphid’

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‘Black Swallowtail Oviposit’ (Look closely and you can see other eggs)

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‘…and the ensuing Black Swallowtail caterpillar swarm….’

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‘Micheaux Lily bulbs’

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‘Chrysoganum close up’

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‘Tiny native bee coming in for a landing on Columbine’

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‘Hoverfly lined up with Sisyrinchium petals’

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‘Marshallia blooms at sunset’

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‘Tiny Caterpillar using Rudbeckia flower parts as cover’

HAPPY NEW YEAR!!


Miniature Worlds: Milkweed Edition

Every plant is a microcosm of the larger world if you look closely. Creatures go about their lives, feeding, mating and reproducing in their little corner of existence unaware of the larger world just beyond the edge of the leaf. Most plants have co-evolved with their insect predators, and with each new defensive adaptation comes a new insect feeding strategy. Specialized plant defenses lead to specialized insect plant eaters and then specialized insect predators that feed upon them. Unique, interdependent communities of plants and animals slowly take shape over the eons. Plants are the foundation upon which these communities are built, the necessary stage on which all the characters will play out their roles.

Milkweeds (Asclepias spp.) are host to a number of insects that are well adapted to feed on this otherwise toxic plant. The most famous is the Monarch Butterfly caterpillar, which like all caterpillars starts out tiny:

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Those lines in the background are my fingerprints. Caterpillars grow quickly because they eat, and eat, and eat. That’s really all they do is eat and grow through stages called instars as they covert leaf matter into body mass. In the final stages they are much larger:
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The bright colors are to warn would be predators (i.e. birds) that their bodies are full of foul tasting, potentially poisonous compounds from the milkweed leaves.

Monarch caterpillars aren’t the only ones to eat milkweed, or to have those black and yellow stripes. The Milkweed Tussock Moth caterpillars (Euchaetes egle) also display the black and yellow warning signs:
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They also have long stiff hairs to deter birds from trying to eat them. Unlike Monarchs, these caterpillars are gregarious and will congregate in large groups. This swarm defoliated 6 plants before I isolated them. The plants have evolved with this, and respond with a new burst of leaf growth a week or two later once the ravenous caterpillars have starved or pupated.

Another denizen of the milkweed patch is the aptly named Large Milkweed Bug (Oncopeltus fasciatus). It also sports bright colors to warn of the toxins it has ingested.
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Seen here are the smaller, wingless nymph stage at left and the winged adult on the right. They are reluctant to stay still long enough for a good picture because I am more often hunting them down with a can of soapy water than a camera. These insects have specialized mouth parts to pierce milkweed seed pods and devour the seeds inside. I am trying quite hard to get fertile milkweed seeds even without them eating the pods, so a watery grave is all I have for them.

Oleander aphids (Aphis nerii) also present problems for those who grow and sell milkweed plants. They are an invasive insect in the US, as they evolved feeding on Oleander plants in the Mediterranean region. Oleander plants just happen to produce the same defensive chemicals, cardiac glycosides, that Milkweed plants do. When Oleander was introduced to the US as a garden plant the aphids came with it and soon began to feed on the native milkweeds as well.
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They are now pretty much synonymous with milkweed, and can rob the plant of its energy by sucking out the juices from leaves and stems. As if that wasn’t bad enough, the aphids secrete a sugary substance called honeydew from their backsides, and this often nurtures the growth of fungi on the plant that can further weaken it and lead to the death of the plant. Controlling the spread of these nasty aphids can be tough. The simplest method is to blast them off the plants with a jet of water. It doesn’t necessarily kill them, but gives the plant a respite until they find their way back. Soapy water is another favorite, and it will actually kill them.
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Soapy water also kills caterpillars and the eggs they hatch from though, so I’ve pretty much given up on spraying the plants with it. I usually just spot treat the larger infestations by knocking the aphids into my trusty can of soapy water. Spraying Neem Oil or soapy water will reduce the aphid numbers, but it will also kill off numerous unrelated insects (like caterpillars) and aphid predators as well. One positive sign I have noticed since discontinuing spraying is the presence of more Ladybug (Coccinella spp.) larvae. The little crocodile-looking larva are predators that love to eat aphids and numerous other plant-feeding insects.
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After eating lots of aphids they pupate into the cheery red and black beetles that continue to feed on many of the insects that we call “crop pests.” Yet another reason to plant milkweed, as the ladybugs and their larvae do not distinguish between the green native aphids and the yellow invasive ones. It’s just another food source that will keep them around to guard your other plants.

Those are just a few of the insects that call Milkweed home. You can invite them into your community simply by planting any of the multiple Asclepias species and they will find it. Of that you can be sure.
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Caterpillars Are Eating My Plants…..and I’m OK With That.

As Summer is upon us, and with a wet spring for encouragement, all of our plants are making verdant new growth. I add fertilizer to the equation to coax even larger, more luscious foliage and flowers from them. This is a common practice in most forms of agriculture and gardening, so most people should have learned by now that all that new growth is a nutrient-dense, tender, food source. As such, we shouldn’t be surprised when insects show up to fill their bellies and feed their offspring. Some insects can be devastating to plants: devouring the foliage, spreading fungal or bacterial diseases, eating the roots, or, something we especially despise here at BHF, eating the seed pods before they can develop. Milkweed Bugs, Leafcutters, Grasshoppers, Lacewings, and Mealybugs all have challenged my patience and devotion to organic practices on more than one occasion. As much as the previous insects fill me with consternation, there is one group of leaf munching insects that I greet with amusement and curiosity: Caterpillars.

Lerema accius
Like this one that was hiding in the base of a rolled up leaf of River Oats (Chasmanthium latifolium). Many caterpillars feed at night and then spend the day hiding in a rolled up leaf, or clinging to plant’s stem hoping to avoid detection by birds and the numerous other predators that would eat them. Part of the fun of finding them is that they are trying very hard not to be found, so it’s usually a surprise. The other fun part is trying to identify the species and see what sort of butterfly or moth it will become. I’m pretty sure this one is a Clouded Skipper which feeds on various broad leaf grasses.

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This one is going to grow up to be a moth: a Gray Half Spot to be exact. It is a more specialized species in that it only feeds on St John’s Wort (Hypericum spp.), and has developed adaptations to blend in with those plants. The bark of St John’s Wort has a dark reddish/burgundy coloring, and so does this caterpillar hiding in plain sight on a stem of Cedarglade St John’s Wort (Hypericum frondosum) seedling. I especially like finding specialists like this one because they are so exacting in their food requirements that they are almost by definition less common than their generalist cousins.

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Speaking of specialist caterpillars, here is their charismatic poster child: The Monarch. Their food source is Milkweed (Asclepias spp.), a plant that is toxic to most other creatures. Compounds in the sap called cardiac glycosides will disrupt the heartbeat and possibly stop the heart altogether if too much of the plant is consumed. Monarch caterpillars and butterflies have evolved immunity to the effects of the plant’s defenses, and also incorporate the toxic compounds into their bodies which discourages predation by birds. This evolutionary strategy of eating toxic plants and utilizing their chemical defenses is shared by several other species of caterpillars including Pipevine Swallowtails, Ornate Moths, and Cinnabar Moths.

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Here’s a few that are eating a non-toxic plant: the apple tree in my front yard. This is where the “I’m OK with it” can be put to the test. No one tends to care if caterpillars are eating the toxic weeds on the wayside, but when they start moving in on plants we wanted to eat, well, they might have to go. I am OK though because I know that they aren’t going to do any long term damage to the tree, especially since they are most likely going to get picked off by birds before they get a chance to spin cocoons. Each caterpillar only needs a few leaves from the plant to reach adulthood, and in this specific instance I don’t even want the leaves; I want apples. Also, this tree is not even old enough to make apples yet, so for the time being it’s just making caterpillar food. Apple and Crabapple trees (Malus spp.) host over 300 species of caterpillars, so it’s doing a great job of that, and still has plenty of leaves and continues to shoot upward.

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This one isn’t a caterpillar at all. It just looks and acts like one. It is a Sawfly larva of the genus Macrophya. It took me a good bit of searching to figure that out because I was operating under the assumption that it was a caterpillar. Sawflies, like butterflies, lay their eggs on specific host plants, and this one uses Elderberry (Sambucus spp.). Interesting to note that Elderberry leaves and stems are toxic, so it looks like these sawflies have similarly adapted an immunity and utilization strategy like the Monarchs.

Caterpillars are critical links in the food web. They facilitate the last leg of the transformation of the sun’s energy into protein. Protein that is a critical food source for many other animals, especially when they are young and growing rapidly. A few tattered leaves on our ornamental plants are a small price to pay to ensure the proper development and survival of a clutch of baby birds. The lucky caterpillars that do escape predation and become butterflies or moths will pollinate the same plants that sustained them as larvae (and many others!), thus ensuring a new generation of plants to keep the circle rolling right along just as it has for millions of years.