Sunday, April 18, 2010

Wood Spurge - Euphorbia commutata

Wood spurge (Euphorbia commutata) is a member of the Euphorbia family and quite rare in Florida.  It is reported from only two counties in the Florida panhandle in rich calcareous woods, and from 2 counties in northern west-central Florida in and around the Brooksville Ridge.  Because of its limited distribution, it is classified as a state endangered species. 
Woodland spurge is a beautiful bright lime green and sprawls in multiple directions from the main stem.  Eventually, individual plants may stand nearly 1 foot tall and more than that across.  Flowering occurs in the early spring.  The individual male and female flowers are surrounded by a round bract.  Eventually, the female flowers produce a three-chambered capsule with tiny seeds.
Wood spurge has never been offered commercially to the home gardener and is not likely to.  It obviously has some ability to thrive across much of the northern third of the state, but also seems to require alkaline soils and rich deciduous woodlands.  Although these conditions could be duplicated in home landscapes - especially near home foundations on the north side, this plant's lack of showy blooms would relegate it to use by the true connoiseurs of the unique. 
This is yet another one of Florida's interesting flora that we should admire in the wild and take pride in its preservation.

Mountain Spurge - Pachysandra procumbens

Mountain spurge (Pachysandra procumbens) is exceedingly rare in Florida, being found only in calcareous woodland habitat in Jackson County; the region in and around Florida Caverns State Park.  It is a state endangered species, but its range extends throughout much of the Southeast Coastal Plain and it is more common in the lower Appalachians. 
Mountain spurge is characterized by its palmate leaves, each leaflet with noticeable teeth along the outer margin. The older leaves are spotted as shown in the second photograph above, though the newer leaves are lighter in color and the spots are barely visible.  These leaves stay close to the ground surface and stand only a few inches above it. 
Flowering occurs in the spring.  The elongated racemes of white flowers appear many inches away from the basal leaves, arising from the ground on a separate spike.  Each flower is composed of spidery petals, tipped in pinkish brown.  They are not especially showy, but quite interesting to observe.
Mountain spurge will never likely be offered in Florida from Florida stock for home gardeners.  It would make a very interesting groundcover wildflower for deciduous woodland gardens with alkaline soils - the same environment that would support trilliums, Walter's violet, fringed campion and the like, but its rarity and lack of showy bloom will likely keep it as one of Florida's many rare and interesting "oddballs" - species left here after the last ice age in small pockets of habitat more in line with the present climate of the Appalachian Mountains.  It is enough that this interesting wildflower maintains its foothold here in Florida Caverns State Park.

Sunday, March 28, 2010

Mayapple - Podophyllum peltatum

Mayapple (Podophyllum peltatum) is one of several northern species which finds its southern terminus in a few special places in north Florida.  This was always one of my favorite early woodland wildflowers while growing up in southern Wisconsin.  In Florida, it is confined to Jackson County; specifically the area in and adjacent to Florida Caverns State Park.  Here, it thrives in the rich deciduous forest floor in soils influenced by limestone near the surface.
In early spring, mayapple sends its solitary leaf up and out of the leaf litter.  It looks something like an unfurled beach umbrella at this time.  Once fully up, the leaf unfolds and forms an umbrella over the single white flower.  The leaves are quite large; reaching a diameter of nearly 1 foot.  The flowers are also large and may be 2 inches in diameter.  Pollinated flowers form a green, apple-like fruit that ripens in summer.
Mayapple is sold by a large number of northern native plant nurseries, but no nursery in Florida propagates it and none are likely to in the future.  Its narrow growing requirements in Florida make it a difficult species to provide for here.  As such, it is best admired in nature and not coveted for the home landscape.

Underwood's Wakerobin - Trillium underwoodii

Underwood's wakerobin (Trillium underwoodii) is found in the understory of hardwood hammocks throughout much of the eastern half of the Panhandle.  Like other native trilliums, it prefers calcareous soils and emerges in early spring before the canopy leafs out.  In some respects, it looks similar to the spotted wakerobin, but the stems are much shorter and the plants stand just inches above the forest leaf litter.  These photos were taken at Torreya State Park and in Angus Gholson County Park, near Chattahootchie.
We have grown Underwood's wakerobin in our Pinellas County woodland landscape for three years now, and though it has not prospered in the same way the specimens above have, they have bloomed and slowly multiplied.  If you wish to attempt any of the native Florida trilliums in your landscape, give them soils with good drainage, high pH, and abundant leaf litter on the surface.  Make sure the growing location is sunny in the late winter and spring and shady the rest of the year.  Many spring-blooming ephemerals will do well outside of their range, but they require deciduous forests - not live oak dominated ones. If you wish to try them, several nurseries are currently propagating them from seed.  Make sure you purchase your plants from reputable sources.

Friday, March 26, 2010

Spotted Wakerobin - Trillium maculatum

One of Florida's other four spectacular trilliums is spotted wakerobin (Trillium maculatum).  This species has much the same distribution as Chattahootchie River wakerobin, but it occurs eastward into Alachua County as well.  These photographs were taken the same day as the photos taken of Chattahootchie River wakerobin in Florida Caverns State Park near Marianna, Jackson County, Florida.  Spotted wakrobin has similar leaves and stands the same distance above the ground.  The most obvious difference lies in the shape of the petals.  Both the petals and the sepals are a rich maroon in color and the petals are erect and several inches in length.
Spotted wakerobin, like all our native trilliums, is confined to the understories of deciduous forests in soils overlying limestone.  In these settings, their populations can be quite dense and they are especially noticeable in the spring.  As summer approaches, the leaves wither and disappear - only to emerge again the next spring.
Spotted wakerobin makes an extremely interesting addition to a deciduous hardwood understory planting and is available from a few reputable nurseries which propagate it from seed.  Do not attempt it if you cannot duplicate the conditions it requires - good drainage with a rich organic surface layer and high alkalinity.  Under these conditions, it is relatively easy to grow - even outside its normal range.

Chattahootchie River Wakerobin - Trillium decipiens

Chattahootchie River wakerobin (Trillium decipiens) is one of the most unique of Florida's four native trilliums.  In Florida, it is only known from 2 counties in the central Panhandle and it occurs only sporadically elsewhere in Georgia and Alabama.  The photos above were taken in Florida Caverns State Park outside Marianna in Jackson County.  All of our native trilliums bloom in early spring and occur in the understory of deciduous hardwood hammocks on top of limestone outcroppings.  The population at Florida Caverns is nothing short of spectacular.
All of our native trilliums have three-lobed mottled leaves.  In Chattahoochie wakerobin, these leaves are on a rather long stem and stand 6-8 inches above the ground.  The reproductive portions of the flowers of all trilliums are quite small and hidden inside the showy petals.  In this species, the petals are several inches long and vary between yellow and maroon in color. 
Trilliums require the conditions found in the understory of deciduous hardwoods hammocks to prosper and should not be attempted in the home landscape unless these conditions can be duplicated - well-drained sandy soils overlain with leaf litter.  Also of extreme importance is the presence of limestone.  This species, and its other Florida relatives, are offered by a few reputable nurseries who propagate them from seed.  Do not purchase plants from others who may dig them from wild populations.  If you can provide the conditions this species requires, trilliums make for extremely interesting additions to a woodland understory planting.

Thursday, February 25, 2010

Curtiss' Milkweed - Asclepias curtissii

Curtiss' milkweed is an extremely rare endemic species, listed as endangered by the state and confined to deep excessively well-drained sandy habitats in the peninsula.   Although widespread throughout the peninsula, its populations are widely scattered and localized.  It occurs only in excessively well drained sands with lots of sunlight.  
This deciduous species eventually becomes quite long and lanky.  The thick main stems may reach 2-4 feet long, but they often lean over and this makes them seem shorter.  The leaves are deep green and oval in shape, usually with a noticeable undulating margin. 
Flowering occurs in the summer.  The few flower heads (umbels) are confined to the ends of the main stalk and consist of 20-30 individual flower buds.  These open to become clear white in color.
Although Curtiss' milkweed would make an excellent addition to a butterfly garden, given its abundant foliage and large stature, I am not aware of anyone ever propagating it.  Perhaps this will change someday given the increased interest in native plants and butterfly gardening.  Until then, we can only hope that the wild populations will be protected sufficiently to maintain this interesting and truly Florida species in our flora.