Sunday, March 22, 2015

Spring Trees - Alternatives

As I walked through my neighborhood the other day, my view was filled with blooming ornamental pears (Pyrus calleryana ‘Bradford’ and others). This neighborhood is about 25 years old and that was a popular landscaping choice then. Thankfully it is less popular now.   

American plum (Prunus americana) in late March

Ornamental spring-blooming trees from other places (Asia, Europe, etc.) are a big part of the selection available to the average gardener. Are non-native trees the only choices for spring blooms in the landscape? Of course, the answer is no. The wild lands of Georgia were full of spring-blooming trees long before Europeans arrived on these shores. Those native trees are perfect candidates for our gardens even today.

Red maple (Acer rubrum) – the earliest tree to bloom with small but numerous red flowers that provide pollen and nectar for early bees. Red maple is also very adaptable to a variety of growing conditions.

Redbud (Cercis canadensis) – pale purple flowers often peek out at us from roadsides, but this tree provides a beautiful shape in the garden and bees love the flowers too. Several cultivars are available.

Serviceberry (Amelanchier arborea and other species) – soft white blossoms flutter in spring breezes. These flowers turn into tasty fruit used by early settlers as well as highly sought after by birds.

Plums (Prunus americana and others) – white flowers are held close to the branch but they light up the tree because they are so numerous. Pollinated flowers become juicy small fruits favored by humans and wildlife alike.

Hawthorn (Crataegus sp.) – clusters of white flowers are joined by emerging leaves to create a pleasing effect. Clusters of bright red berries appear in summer and persist into fall, waiting for flocks of birds to discover them. Several cultivars are available.

Hawthorn (Crataegus viridis 'Winter King') at the elementary school nearby

Black cherry (Prunus serotina) – elongated clusters of creamy flowers provide a feast for native bees. Ripening berries beckon birds who often find tasty caterpillars too.

Sassafras (Sassafras albidum) – pale yellow flowers are held in clusters before the leaves emerge. Only female flowers turn into the showy blue and red fruits. The tree also provides one of the best fall color shows around.

Crabapple (Malus angustifolia) – southern crabapple flowers are pale pink and can be delightfully fragrant. Edible small fruits follow and were often used by early settlers.

Crabapple (Malus angustifolia

Red buckeye (Aesculus pavia) – is a small tree form shrub that is perfect for small spaces. The early flowers are an important source of nectar for returning hummingbirds and bees.

Fringetree (Chionanthus virginica) – the delicate white petals are especially showy on male trees, but it is the female that produces the dark blue berries in the fall. As a specimen tree, this one never fails to grab attention.

Pagoda dogwood (Cornus alternifolia) – a lesser known species of dogwood, this one has alternate leaves and an especially pleasing shape. Tiny flowers held in clusters turn into fruit that is much appreciated by birds.

Pagoda dogwood (Cornus alternifolia)

Flowering dogwood (Cornus florida) – a long admired ornamental tree, this is generally available as cultivars in nurseries. Tiny flowers surrounded by large white bracts turn into showy red fruits that birds love. Don’t be fooled by Kousa dogwood, it is not native.

Silverbell (Halesia sp.) - this small to medium tree is perfect for a specimen tree location. The showy white bells decorate a gracefully shaped tree.

Snowbell (Styrax grandifolius and S. americana) - similar to the silverbell, but the white petals are more open to show the yellow stamens.

Bigleaf snowbell (Styrax grandifolius)

Wow, that is a lot of choices once you write them all down! I hope that if you are looking for something native that you can find something on this list to suit you and your landscape conditions.

Sunday, March 15, 2015

Winning Weeds

About the time that the common violets (Viola sororia) started blooming this week, Doug Tallamy had an op-ed in the New York Times about essential plant/insect relationships. For those of you that haven’t heard of Dr. Tallamy and his entomological message about plants and insects, it’s a compelling tale. If you know about the monarch butterfly and its relationship with milkweed (Asclepias sp.) then you already have the gist of it.

Tiny bluets (Houstonia) can be found in thin grassy areas

The op-ed included a photo gallery of plants and wildlife (insects, birds, and others - beautiful pictures as always) that have a relationship with those plants. While some relationships were about wildlife that eat the plants’ fruit, others were about insects that use the plants as larval hosts: monarch butterflies and milkweed, zebra swallowtail butterflies and paw paws (Asimina sp.), and violets (Viola sp.) and fritillary butterflies.

Of course the common violet is considered a pesky lawn weed by many folks but it’s time that it and other “weeds” get the credit they deserve for their important role in keeping butterflies flying. Here are just a few of the butterflies that depend on plants that might otherwise be considered weeds:

Great spangled fritillary butterfly – Violets (Viola sp.)
American lady butterfly – pussytoes (Antennaria  sp.), cudweed (Gnaphalium sp.), and ragwort (Senecio sp.)
Spotted thyris moth – bluets (Houstonia sp.)
Skippers, wood nymphs and satyrs – native grasses (Panicum sp., Andropogon sp. and others)
Cloudless sulphurs – native legumes such as partridge pea (Chamaecrista sp.)
Gray hairstreaks, skippers and eastern tailed blues – tick-trefoil (Desmodium sp. and related plants)
Question mark, comma, painted lady, and red admiral butterflies – nettles (Urtica sp. and related plants)

Cloudless sulphur butterfly

The next time that you come across a "weed" and decide to get rid of it, you might just want to check whose breakfast, lunch and dinner it is. Some of these native weeds are real winners.

Red admiral butterfly

Now if you'll excuse me, I think I need to go find some nettles.

If you're interested in learning more about butterflies? Check out the North American Butterfly Association and its new Georgia chapter. 

Sunday, March 8, 2015

Connect the Dots For a More Natural Landscape

Trees are wonderful things and I love to see them planted in suburban landscapes. In today’s smaller lots, they are often plopped right in the middle of a lawn with a neat ring of mulch around them. Having mowed a lawn or two, I can’t help but think about how difficult that is to mow around.

This tree ring could be connected to the bed behind it
Some people put several of these in their lawn, each one with a dedicated circle of mulch. Each circular object probably adds 3-4 minutes to the mowing job, making it even more of a chore.

These mini islands of arboriculture are more than just a pain in the neck, they are downright unnatural and not healthy for the trees.

What a chore!

How unnecessary to separate these!

In nature, trees are arranged in groups with natural leaf litter covering the ground around them. The deep and wide expanse of that leaf litter allows surface roots to be protected and fosters a healthy population of the bugs, worms and fungi that support the tree. Those bugs, worms and fungi help break down those leaves, releasing nutrients at root level for the tree.

Special types of fungi, called mycorrhizal fungi, forge relationships with the rootlets of the tree, helping to bring even more nutrients and moisture to the tree. The fungi benefit from the relationship as well, and this win-win arrangement contributes to your tree being healthy and happy.

You might think that the mulch ring around your tree performs a similar role, but tree roots extend farther than you think. Arranging trees in a group brings not only a more natural look but also benefits to the soil with more root cover.

Here a single large bed handles trees and shrubs

A simple path is all that is needed for access to the back

There are several other benefits to connecting your tree dots. Standalone tree circles chop up what might already be a small yard, emphasizing even more how small the area is. Joining smaller beds together creates a smoother look and using wide curves evokes a more natural landscape. Mowing chores will be easier and take less time.

An example of trees in a large, joined bed

A more natural look puts trees in a group

An alternative to grass paths 
With wider beds and less grass, you can incorporate more interesting plants like perennials or annuals.

For shady areas, use native ferns. For sunny areas, pollinator-powerhouses like perennial sunflowers, coneflowers and black-eyed Susans will contribute more to the local pollinators than the lawn ever would.

When you're ready to support more of nature, connect the dots in your landscape. I think you'll find it to be a win-win solution.

Sunday, March 1, 2015

A Perfect Plant for Birds in Georgia

Finding the perfect plant for gardeners who want to support birds would be a wonderful thing. Every bird lover would rush to purchase such a plant. Time to be amazed: such a plant exists and is native throughout Georgia. The plant is black cherry (Prunus serotina) - pronounced PROO-nus sair-OTT-ih-nuh - and it is found from far northern Georgia to the very southernmost counties. From east to west and north to south, black cherry thrives in the varied soils and climate of Georgia.

Black cherry (Prunus serotina) in bloom

Knowing what birds eat is the key to understanding why this plant, and its close native relatives, is such an ideal plant. Here is a quick review of the diet of adult birds. Adult birds, you see, are rather specific eaters.

Female red-bellied woodpecker on suet
Those adults that eat seed will flock to your seed feeders: cardinals, goldfinches, pine siskins, sparrows and finches of all kinds. You’ll also get birds like mourning doves, titmice, chickadees, bluejays and the occasional woodpecker. If you have some suet feeders, especially in winter, then you’ll bring in birds like warblers, wrens, bluebirds, and more woodpeckers that need some high energy food. Cold temps and snow cover will encourage even more species to stop by for a winter bite.

The plump fruits of black cherry 

In the spring and summer, birds focus more on their traditional adult diet and that’s where black cherry really shines. Birds that are frugivores (fruit is a large part of their diet) thrive on the small fruits of the native cherry trees, and as many as 53 different species of birds have been observed eating them (not all of them frugivores). These include birds like cedar waxwings, mockingbirds, catbirds and tanagers. Other wildlife eat the fruit too.

While adult diet is very important, we need also consider the diet of baby birds. That’s where the foliage of black cherry is important. A large percent of baby birds are raised on insects – 96% of bird species feed insects to their chicks. It takes an enormous amount of insects to feed just one clutch: an estimated 6000 to 9000 insects for a nest of chickadees and those are small birds.

Caterpillar of Furcula borealis on black cherry
While some of those insects are spiders and other things, most of them are caterpillars. Birds find caterpillars on the leaves of plants, primarily native plants. As most of you know, caterpillars are the larval form of butterflies and moths. Our native butterflies and moths have host plant relationships (think monarch butterfly and milkweed) with the plants they evolved with. Watch an entomologist explain it better in this short video.

Black cherry happens to be a host plant for over 450 different species of butterflies and moths. Species include those as familiar and beautiful as the Red-spotted Purple, the Viceroy, the American Lady, the Cecropia silkmoth, the Coral Hairstreak, and our state butterfly, the Eastern Tiger Swallowtail.

Of course there are still many more species, some of them drab colored moths (see White Furcula moth pictured) that we don’t notice. These make up the bulk of the caterpillar population that feeds these birds; they are most of the 6000-9000 insects that are needed to raise just one set of baby birds.

The yellow-rumped warbler eats insects in the spring and summer
You'll also be supporting the many adult birds that rely on an insect diet. Birds that are insectivores include the warblers, flycatchers like the Eastern phoebe, bluebirds, wrens, robins and our state bird, the brown thrasher.

The flowers of black cherry are numerous and attract a wide variety of pollinating insects, especially native bees of several types. If you like to support native bees, you now have another reason to want black cherry in your landscape.

All in all, black cherry has extremely high wildlife value. If you only want to have it for the birds, that reason is plenty is good enough. All the other critters will enjoy the fringe benefits.

Sunday, February 22, 2015

The Solution to Fewer Native Plants is Fewer Native Plants?

Recently someone on a message board was advocating that we respond to the decline in native plants by planting more non-native plants. The issue in question was having fewer nectar sources for butterflies due to habitat destruction and development of wild lands into subdivisions, shopping areas and commercial real estate.

This is not the first time that I've seen someone advocate using non-native plants specifically because there are fewer native nectar sources than before. It implies a “we can make nature better” mindset.

This approach demonstrates a lack of understanding in regards to insect life cycle, a lack that was all the more startling given that it was being demonstrated by someone that was arguing on behalf of the monarch butterfly. The monarch butterfly is THE “poster butterfly” for the larval-host plant relationship. Monarchs need milkweed (Asclepias spp.) to lay their eggs on, right? Without milkweed plants, monarch butterflies cannot survive and the last two years have dramatically demonstrated that.

One cannot focus only on nectar plants - nectar is only used by the adults. The needs of the larvae are completely different from the adults. By advocating that non-native plants be used for nectar instead of the nectar-producing natives that disappeared, this person is saying that some butterflies and moths are more worthy than others.

This wingstem (Verbesina alternifolia) supports bees, provides nectar, and  is a host plant

You see, the rest of the native Lepidoptera (butterflies and moths) in North America have similar relationships with their own host plants just like monarchs and milkweed and they need those plants to be available as well. Goldenrod (Solidago spp.) is a top native late summer nectar plant and host to well over 100 different species of butterflies and moths. Here is a short list of some of those special relationships:

  • Silvery Checkerspot (Chlosyne nycteis): host plants include native sunflowers (Helianthus spp.) and common wingstem/crownbeard (Verbesina spp.).
  • Gulf Fritillary (Agraulis vanillae) and Zebra Longwing (Heliconius charithonia vazquezae): both of these lay eggs only on members of the passionvine (Passiflora spp.).
  • Great Spangled Fritillary (Speyeria cybele): host plant is violet genus only (Viola spp.).
  • Zebra Swallowtail (Eurytides marcellus): host plant is only paw paw (Asimina spp.)
  • Great Purple Hairstreak (Atlides halesus): Mistletoe (Phoradendron tomentosum).
  • Henry's Elfin (Callophrys henrici): Redbud (Cercis canadensis).
  • American Lady (Vanessa virginiensis): host plants include cudweed (Gnaphalium) and pussytoes (Antennaria).
  • Cloudless Sulphur (Phoebis sennae) and Sleepy Orange (Abaeis nicippe): both host on what most people might consider weedy legume plants like partridge pea (Chamaecrista fasciculata) and sickle-pod (Senna obtusifolia).
  • Coral Hairstreak (Satyrium titus): Sandhill plum (Prunus angustifolia), and black cherry (Prunus serotina).
  • Spicebush Swallowtail (Papilio troilus): hosts on spicebush (Lindera benzoin), sassafras (Sassafras albidum), tuliptree (Liriodendron tulipifera).
Some Lepidoptera are even named for their host relationships: Hackberry Emperor (Asterocampa celtis) hosts on hackberry (Celtis spp.), the Yucca Giant Skipper (Megathymus yuccae) hosts on Yucca, and Pipevine Swallowtail (Battus philenor) hosts on pipevine (Aristolochia).

This Red Admiral butterfly hosts on stinging nettles

There are some species that have evolved relationships with more than one host such as the Painted Lady (Vanessa cardui) and Common Buckeye (Junonia coenia). Those butterflies have choices, but still they are hosting on native plants, not crape myrtle, not ligustrum, not forsythia or knock-out roses and definitely not on butterfly bush (Buddleja).

While this Zebra Longwing happily nectars on Lantana, there won't be any new ones
unless you have passionvine (Passiflora)

"What about Black Swallowtail butterflies?", you say. They lay their eggs on parsley and fennel, two non-native herbs that are frequently used in "butterfly" gardens. The scientific answer is that both parsley and fennel are in the Apiaceae family which is the same family that contains the native host plants for this butterfly. These same butterflies would naturally host on plants like golden Alexander (Zizia aurea) and any species of Angelica as well as many other native members of the Apiaceae family. Black Swallowtails benefit from this close chemical similarity in plants.

Golden Alexander (Zizia aurea) hosts Black Swallowtail butterflies

For the vast majority of Lepidoptera, however, when you choose to use non-native plants for nectar, you are depriving another Lepidoptera of its host plant. I’m not suggesting this is always a big deal, especially when done in moderation and in consideration of 3 things: quantity, quality and invasive tendencies:

Quantity: having relatively few non-native plants while having mostly native plants is the best approach.
Quality: choosing non-native plants that have abundant nectar and pollen gives you the most bang for the space.
Invasive tendencies: avoiding non-native plants that have invasive tendencies in your area is important.

I will plant a few non-native nectar sources this year, but I'll be mindful of those 3 considerations when I make my choices. We can help some butterflies without hurting others if we make informed choices. 

Nature has already set these relationships between plants and Lepidoptera. We can't change them and we can't make nature "better." We can understand them and we can help to keep them going. That's why we have the big brains.

Sunday, February 15, 2015

Avoid the 'Noids in 2015

This subject is on my mind way too often, but I don’t want to be the only one thinking about it. We all need to be concerned and educated when it comes time to choose our plants this spring.

I’m talking about neonicotinoids (NEO-nik-oh-teh-noids). Neonicotinoids are a type of pesticide that has been widely touted in the last few years as a “safer” type of pesticide against sap-sucking and leaf-chewing insects because it is taken up by the plant through the roots (it is watered in or applied to the seed as a pre-treatment) and doesn’t involve the hazards to humans from treatments like spraying.

These pesticides have been found to not be “safe” for insects that eat or gather pollen and nectar from the treated plants because there are residual amounts of the chemical in the pollen and nectar. That means we don't want these chemicals applied to any plants that require insect pollination (like our fruits and vegetables) or the plants that we use to attract and sustain butterflies.

Neonicotinoids are now considered a likely contributor to problems with bees, problems as serious as killing them outright or at least causing disorientation such that they cannot find their way back to their hives (in the case of European honey bees) or their nests (in the case of native bees). Bees leave the hive or nest to gather pollen and nectar to bring back. Along the way, they will eat some of what they gather for their own nourishment.

Frankly if they cannot find their way back to the hive or nest, they are as good as dead anyway because they are not helping the next generation of bees.  

So what's a conscientious gardener to do? Both plants and seeds need to be considered. One approach is to pre-research everything. A blogger on the West Coast has put together a fabulous collection of information on many of the large growers and seed providers. She contacted them and has published their responses. 

Gardeners who are concerned about purchasing products treated with neonicotinoids have asked for companies to label their plants so that treated plants can be avoided. The Home Depot announced last year that they would require their suppliers to let them know about treatments so that they could label the plants. Bravo! I'm not aware of any other major plant retailer in Georgia that has agreed to provide labeling.

Blueberries treated with neonics

The new labels have now arrived at Home Depot and I thought I'd take a field trip to see how plants and seeds are being labeled there. What is clear is that the labeling on plants is being used to definitely indicate which plants have been treated. Plants that are not labeled can - I assume - be considered as not having been treated by neonics. 

Or the label fell out. Or that pot was missed. You might have to search around to see if other plants (same kind of plant) in the area have tags and the one you picked up was just not labeled. You can see here that the label is just tucked into the pot, and sometimes it is shoved all the way to the soil line.

Here is a picture of the label and it looks like they are probably being applied at the store once the plants are delivered (in other words, it is Home Depot's tag, not the grower's tag). 

I examined all the seed packets at Home Depot and none of them are labeled for neonicotinoids. Several have "non-GMO" labels but that is not the same thing. One package was labeled as "organic" but I am not sure that is a guarantee.

This package happens to be from Ferry-Morse which is not using neonics according to the blog on referenced earlier. It would be more clear if they'd say that.

Non-GMO does not mean no neonics
Does organic mean no neonics?

You also need to consider the pesticide products that are sold for use in the home garden. Look at the labels. Neonicotinoids include chemicals like imidacloprid, clothianidin, thiamethoxam, acetamiprid, and dinotefuran so look for these on the labels. The Xerces Society has a great page about products that are available for home use and which ones should be avoided by consumers.

So if protecting pollinators (bees, butterflies, etc.) is important to you, start reading labels - plant labels and package labels. If you're not sure, ask at the store. Retailers won't realize it is important to us unless we speak up.

Sunday, February 8, 2015

Awaiting the Turn from Brown to Green

American beech (Fagus grandifolia)
As we move into February, warmish and sunny days tease our senses. We long for spring, but these are some of the brownest days of all. 

Perennial stems, once tall and straight even in death, have collapsed under the rains and cold nights. Their ragged, soggy limbs lie crumpled against the withered leaves of fall.

Sparkling rays of sunshine fall on empty seed capsules, highlighting their vacant vessels. Their job is done and their emptiness has a beauty of its own. After all, the capsule is a testament to their fertility.

Hibiscus coccineus capsule

Among the brown, in Georgia, there are spots of green. They are plants that never really go away; they are just dozing in the sunshine. I’m sure they are gathering energy; I've never known nature to let good stuff go to waste.  

A Christmas fern (Polystichum acrostichoides) here, an ebony spleenwort (Asplenium platyneuron) there … plus a scattered assortment of perennial herbs like green and gold (Chrysogonum virginianum) and the leafy rosettes of cardinal flower (Lobelia cardinalis).  

Tiny Christmas fern in the grass

I am glad to have the green, but by now I yearn for more than that. I want flowers. I want flowers, not just for themselves but for the rest of life that they bring. With flowers come insects: bees, butterflies, moths and caterpillars. Even flies (flower flies, that is) would be welcome. With insects come birds in abundance. The whole place comes alive!

A few more brown days I must endure. Nature comes in her own time, but … I just saw a single trout lily leaf (Erythronium umbilicatum) poking through the pine straw. The end of brown is near.