Tuesday Florida Native Plant & Wildflower Poetry, Purple Muhly Grass

Tuesday morning Florida native plant and wildflower haiku, Purple Muhly Grass

Florida Wildflower Poetry & Art, Purple Muhly grass, Mulenbergia spp. by Kevin Songer

…
sweetgrass baskets
muhly and pine needles weave
art of carrying rice
…

Purple muhly grass lines the median of many native plant landscaped downtown streets in Florida. During late summer the blooms form a cloud-like top to the grass in brilliant white, purple and pink shades. This grass gives important communal habitat to birds and small mammals and once established is extremely drought tolerant. Muhly grass has a long history of ethnobotanical uses by native Americans and early settlers.  Woven from plant leaf blades, early plantation workers carried rice and other goods up from the fields in muhly grass baskets and satchels.

Muhly grass is a great green roof plant choice too (think C4 photosynthesis).

Green Gardening Matters' post on muhly grass offers helpful hints on growing the grass as well as more of the interesting history of the plant.

Nature's Living Wall Plants

Every season brings a new face one of nature's finest display of living wall plants growing on the stone walls of Castillo De San Marco, St. Augustine, Florida.  St. Augustine is the oldest colonized city in the U.S. and plants have been growing on the hard shell facade of buildings here for centuries.  The fort is an educational paradise for any green roof or living wall designer.

Irrigated only with dew, fog and rain, the wall plants grow out of sheer vertical rock with little or no soil.

Wildlife are drawn to the diverse range of native plants in droves.

Native plants play an important role in supporting worldwide biodiversity heritage.

For a great blog post on just how important native plants are for supporting biodiversity, read the post here at Wildlife Garden.

One of the many ways to learn about native plants in your local downtown area is to 'look up'.  This week I again, spent several hours walking in the moat of the old Spanish Fort in St. Augustine.  In my opinion the National Park Service has it backwards - they charge for going inside the fort but allow you to walk for free in the moat and around the grounds.  The moat is where you can see many, many native and other plants species growing in the coquina walls!

Castillo de San Marco, St. Augustine

As you can see in the above photo, most plants grow underneath the downspouts on the walls.  Though the downspouts provide water primarily when it rains, they also collect dew and fog from surrounding areas and funnel the water to the plants.

Interestingly, learning about green roof and living walls plants from the fort offers insight into those plants that not only do well under the hot Florida sun and with no additional irrigation, but also the plants shed light on soil media composition.

Coquina shell and the limestome mortar have a quite high pH level.  High pH is usually one of the toughest issues to work with on green roofs and living walls.

Samolus valerandi

Florida Green Roofs: Pteris vittata & 2 Cuban anoles

Wildlife seeks out plants, especially those providing resource benefit such as food or nectar or shelter.  Native plants are best suited at providing the most optimum level of ecological benefit to those wildlife endemic to an area.

In otherwords, planting native plants on green roofs and living walls encourages and supports native populations of insects, birds, reptiles, amphibians and other wildlife.

Many popular landscape plants used on green roofs may not offer the same level of resource benefit.

Understanding natural systems through frequent field observations of your local native plants broadens design capabilities for both green roofs and living walls.

Floria Green Roofs: Limestone & Coquina Walls are Harsh Ecosystems

Green Roof Plant Selection. Beauty and the Beast - Are Natives Safe for the Bees?

Using native plants on green and living roofs and across landscapes is currently in vogue for many reasons.

Coral Homeysuckle,  Lonicera sempervires Great Native Plant for Green Roofs

Native plant species typically grow more reliably in a given area than most imported landscape plants.  Additionally, native plant species should be able to survive, once established, without any additional irrigation, fertilization or pesticide usage, so contributing less of a negative impact on the immediate environment.

On the positive side, native plant species can strongly support those insects, pollinators, birds and mammals passing through or endemic to the area.  Research has shown native plant species offer more forage and nutritional value than modern plant hybrids or exotic landscape plants.  So there are many good reasons to use native plant species.

What about negative aspects of native plants?  Are there any?

Yes, possibly.  However the negative aspects are minor in nature, but worth mentioning.  First of all while many native plant species are rather common looking, others have stunning and beautiful flowers.  This has led to the over-harvesting of many native plants from public lands, creating the need to add some native plants, such as wild-azalea here in Florida to the endangered and commercially exploited plant list.

Always purchase native plant species from a reputable and licensed nursery to help preserve native plants in their habitat.

Carolina jessamine or yellow jessamine, Gelsemium sempervirens, is a another showy native plant here in Florida that makes an excellent green roof addition.  Carolina jessamine is presently blooming, making it one of the first native species to flower in the spring.  It is also the South Carolina state flower.

Gelsemium sempervirens, Carolina Jessamine - Green Roof Native

Gelsemium sempervirens, Carolina Jessamine - Green Roof Native

However, when researching Carolina jessamine, there are many warnings about the plant's toxicity.  The plant does contain powerful alkaloids similar to strychnine.  The Cornell University plant website for instance says all parts of the plant are poisonous, depressing central nervous system function and potentially causing death.

Moreover, other institutions and research site, such as Wikipedia, state that the nectar is not only toxic to humans but to bees also, causing brood death.

The reference to brood death and toxicity to humans greatly concerned me for two reasons;

• We plant to adopt bees this year and set up a colony on our green roof, and
• I don't want anyone getting sick from a plant on our greenroof.

And what if the honey were toxic?  Several websites warned of honey from made from Carolina jessamine nectar.  At first, I was determined to dig up the beautiful vine and destroy it.

Then I realized the Wikipedia reference for toxicity to bees was lacking a citation and soon came across another more technical publication in Oecologia that actually pointed out the alkaloids in Carolina jessamine have been used by bees to kill the exotic gut protozoan Crithidia bombi that had been harming bee populations.

So apparently there is research pointing to the fact that Carolina jessamine is nature's medicinal kit for bees, providing a free source of anti-microbial benefits to the bees.

Lets take a step back now.  Bumblebees and others are native to this area.  The honey bees mostly commonly referred to today are considered native to Africa, having then spread to Europe before being imported to the Americas. 

Carolina jessamine, a native species, provides medicine to sick bees, a species that has been imported to food and other uses.  Other literature continues to support the relative safety of having Carolina jessamine around bees by recommending additional variety of other flowering plants complimentary with the jessamine. 

Moderation is always key to success.  Possibly, if the only nectar bees fed on was Carolina jessamine, the honey might be toxic.  There actually have been reported cases of toxic honey made from azaleas, rhododendrons and oleander.  However, integrating a common native into a flowering landscape may provide the bee with natural defenses to its own physical issues and provide beauty and that wonderful spring smell of blooming jessamine.

Beauty and the Beast?  I think not.  For if Carolina jessamine were a deadly killer to both humans and bees then, with its numerous populations across the southeastern US there would be many dead bees and sick humans lying around during spring blooming season.

Respect?  Yes.  Common sense dictates against the use of monocultures.  Provide more than a monoculture of Carolina jessamine. Provide a host of flowering native species and food plants on green roofs and in landscapes.

Native plants are not only to be enjoyed they are also to be respected.   Integrating native species into your green roofs will provide benefit to wildlife and support biodiversity, even to the non-native honeybee.

Nature's own medicine chest.

As always, email your comments and thoughts.

Happy Green Roofing!

Kevin

Green Roof by Nature, Cladina evansii & Wood Shingles

Cladina evansii is commonly referred to in Florida as Deer Moss or Deer Lichen.

Deer moss is an indicator species of clean air.

I found this wood shingle roof today covered in Deer Moss.

Nature Irrigated, Native Species Green Roof Superb.

Cladina evansii Deer Moss Vegetated Roof