Frenchman's Forest

In January of this year, I visited Frenchman's Forest, a natural area in northern Palm Beach County. At that time, we had severe drought conditions and many of the plants were stressed. One indication of that stress was that I had never been to a natural area in which so many different kinds of plants had insect or disease damage.

Most gardeners view insect herbivores and diseases with dismay; however, for the most part, native plants take them in stride and are usually able to resist them when better conditions return. The most serious problems usually lie with introduced, non-native insects and diseases that native (and garden) plants have not had a co-evolutionary history with. Thus, in a natural area like Frenchman's Creek, native insect herbivores and plant pathogens can be viewed as yet another group of organisms that keep things in balance and add to the biodiversity of the natural area.

A single leaf of Chromolaena odorata (jack-in-the-bush) with evidence of three different organisms sustaining themselves on the plant: (1) powdery mildew as seen in the fuzzy white area in the upper left portion of the leaf; (2) leaf miner producing the large milky white area in the upper half of the leaf; and (3) an unidentified organism that is causing the speckling of tiny dots.

Crocanthemum corymbosum (synonym: Helianthemum corymbosum) (pine barren frostweed) is adapted to dry sandy sites and was unaffected by the drought. However, many of the colonies appeared to lack vigor due to overly shady conditions. Long considered congeneric with the Old World Helianthemum, there is molecular genetic evidence that the New World frostweeds should be placed in their own genus (Crocanthemum). See, e.g., Guzmán & Vargas 2009.

Hamelia patens (fire bush) was abundant in Frenchman's Forest and this was the first time that I had seen it as a native plant growing wild in Palm Beach County.

Hamelia patens (fire bush) bears abundant berries that are eaten by various birds and mammals.

Iresine diffusa (blood leaf) has tiny 1-seeded fruits that bear fluffy hairs and are dispersed by the wind. It is a common plant of disturbed, open, sunny and semi-shaded sites in Palm Beach County.

Physalis pubescens arenicola (husk-tomato) was beginning to sprout new shoots from deep, subterranean rhizomes.

Psychotria nervosa (wild-coffee) was abundant at Frenchman's Forest. This carefully rolled up leaf is the handiwork of a moth caterpillar that feeds on wild-coffee.

Psychotria sulzneri (velvet-leaf wild-coffee) tended to grow in more shady or moist areas than Psychotria nervosa. Both plants are outstanding landscape plants whose flowers provide pollen for native bees and nectar for a wide variety of both large and small butterflies. Their red berries are dispersed by birds and provide additional value to wildlife.

Pteridium aquilinum (bracken) grew to enormous heights in one location and covered many square yards of ground.

Richardia grandiflora (large-flowered Mexican-clover) seems to occur in every open, sunny, terrestrial habitat in Palm Beach County. It readily takes over lawns and is now a much-hated lawn weed that is resistant to most broad-leaf herbicides.

Sambucus nigra ssp. canadensis was common at Frenchman's Forest. This plant had foliage with the unmistakable signs of being infected with a plant virus.

Solidago fistulosa (pine barren golderod) was greatly stressed by the drought and was afflicted with powdery mildew as well as by goldenrod blister galls. The latter are caused by the larvae of a tiny midge with the aid of a mutualistic fungus. The larvae never occur without the fungus and there is a possibility that they feed solely on the fungus and never directly eat the leaves (see Stireman et al. 2008).

Stipulicida setacea is a tiny plant that forms rosettes an inch or two wide. It will later bear tiny white or pinkish flowers, each not much bigger than a pinhead.

Vitis rotundifolia (muscadine grape) is sometimes host to a rust (a type of fungus) that produces yellowish to brownish lesions on the leaves.

Images and text © 2012 Rufino Osorio

Okeeheelee County Park Nature Center – Part 1

The following are photographs taken during a hike at the Okeeheelee County Park Nature Center on Friday, December 23, 2011. This set of photographs was taken at the parking lot and at the Visitor's Center. The next set of photographs (Part 2) was taken on the hiking trails.

Immediately upon getting out of my car in the parking lot, I saw a nine-banded armadillo (Dasypus novemcinctus) rooting in the soil for worms or grubs just a few feet from the car. He was completely fearless, or perhaps oblivious, and casually went about his business while I snapped about 4 dozen pictures. Since he was in constant motion, all of the pictures were blurry except for four of them, two of which are reproduced below.

The little pink flowers visible in the armadillo pictures is large-flowered Mexican-clover (Richardia grandiflora), which is seen in close-up below. The plant is neither Mexican nor a clover. It is, in fact, from South America and is in the same family as coffee. It is now one of the most ubiquitous weeds of lawns, roadsides, parks, fields, and the disturbed portions of natural areas in Palm Beach County. It was first seen in Palm Beach County about 15 years ago and in that span of time its population has grown to such an extent that it is perhaps among the top 10 most common herbaceous, non-grassy perennials in the county. It was ever-present along the trails of the nature center and in one area its thick growth was shading a population of the small, native wildflower, Stenandrium dulce (pine pinklet).

The following pictures were all taken around the perimeter of the visitor's center, which is landscaped with both native and non-native butterfly garden plants. These plants were very effective as there were numerous butterflies, both small and large, visiting these plants that day.

Clerodendrum ugandense (blue butterfly plant), from Africa, was in full bloom. It is said to be a minimally invasive Clerodendrum, some of which are extremely aggressive in gardens due to an abundance of root sprouts. In many ways, it reminded me of the native blue curls, Trichostema dichotomum, on steroids, which is not surprising since both plants are in the mint family (Lamiaceae).

And here is an image of the native blue curls, Trichostema dichotomum, for comparison:

Koanophyllon villosum was an interesting addition to the Okeeheelee County Park Nature Center butterfly garden. It is an endangered relative of the thoroughworts (Eupatorium species) and occurs in Florida, as a non-cultivated native plant, only in Miami-Dade County. It is unusual in being a woody shrub, most other related plants in Florida being herbaceous perennials. It bears innumerable tiny white daisies when in full bloom, at which time it is extremely attractive to nectar-seeking butterflies. Of additional interest is the aromatic foliage, which has an unusual mildly spicy scent or, in some forms, a slightly minty scent.

Around the corner from the Koanophyllon, and on the west side of the nature center, was a large clump of Leonotis leonurus, a plant native to Africa. Its bright orange flower buds were extremely attractive and eye-catching . . .

. . . but they opened into slightly dingy-orange flowers. Eagle-eyed readers might notice that the leaves above the flowers in the photo immediately below have crinkled edges. This is due to a viral infection. Such infections were rare in native plants but, as people bring cultivated virus-infected plants into close proximity with native plants, I am beginning to see native plants afflicted with viruses.

After the flowers have faded, they leave behind an interesting set of green calyces.

The aptly named fire-spike (Odontonema cuspidatum) from the American tropics grew in a large clump at the front of the nature center and it was visited by numerous brilliant yellow sulphur butterflies, none of which stood still long enough to be photographed. As one can imagine, the combination of yellow butterflies and bright red flowers created a very colorful scene.

Pentas lanceolata, is one of the most common butterfly garden plants in south Florida; however, I have seen insects visiting this plant exactly twice in 20 years. As usual, no butterflies were to be seen on the brilliant red pentas at the nature center on the day of my visit.

Golden polypody (Phlebodium aureum) grew in a large cabbage palm (Sabal palmetto) and its yellowing leaves provided a bit of "autumn" color on a warm subtropical winter's day. It is a very large fern with a dramatic presence and it is mostly ignored by Florida gardeners, perhaps because it is so common. Were it rare and endangered, it would surely be greatly sought after by plant collectors.

Tropical sage (Salvia coccinea was well-represented in the butterfly garden. This was, of course, no surprise since this native plant is a staple of South Florida butterfly gardens where it attracts both butterflies and hummingbirds. All three color forms—red, pink, and white—were present in the garden.

Another staple of butterfly gardens, and equally attractive to hummingbirds, is Sophora tomentosa (necklace pod). The plant in the image below clearly has leaves densely covered with tiny silvery hairs. This identifies it as the non-native var. occidentalis, whose native range is Texas and tropical America. The Florida native var. truncata has leaves that are hairless, or nearly so, at maturity. In the background, is firebush, Hamelia patens, another favorite of butterfly gardeners.

Go to Part 2.

All images and text © 2010 Rufino Osorio.