Cloverleaf

 

Crimson Clover (Trifolium incarnatum) in a mountain meadow.  
Ashe County, North Carolina. 

Clovers (Trifolium sp.) are small herbaceous plants with a large impact; agriculturally, ecologically and culturally.  Trifolium is a member of family Fabaceae which includes peas, beans, vetches and acacias.  Clovers are usually low growing annuals and are native to all continents except Australia and Antarctica.  A defining characteristic of clovers is their three-part, compound leaves that give the genus its name. 

The leaves of clover play a major role in myth and legend.  Patrick, the patron saint of Ireland, is reputed to have used the three leaflets of clover to explain the Trinity to the pagan Irish he came to convert to Christianity.  However, clovers never appeared in St. Patrick’s writings so this story is probably apocryphal.  The ancient Irish word for clover was corrupted in English to give us shamrock. The association of shamrock/clover with St. Patrick led to its adoption as a symbol of Ireland.

I found a four-leaf and three leaf White Clover (Trifolium repens) in the same patch.  
Rowan County, North Carolina. 

Another interesting tradition is that four-leaf clovers are lucky.  Normally a clover has three leaflets but rarely a plant will make a leaf with four.   Since four-leaf clovers are rare, about 1 in 5000, finding one is considered good luck.  I think finding a four-leaf clover has more to do with persistence than luck.  

Roots of White Clover with root nodules containing
nitrogen fixing bacteria.
Rowan County, North Carolina. 

Clovers make small flowers grouped in compact heads.  They flower from early spring to late summer and are important nectar sources for a variety of bees.  Clover honey has a mild taste and is much in demand.  Clover plants have a high protein content.  Farmers grow it for silage and as a ground cover in crop rotation.  The large amount of protein in clover is a result of nitrogen fixing bacteria (Rhizobium sp) in the roots.  The bacteria invade the roots and induce the plant to make nodules where the Rhizobium converts nitrogen gas to amino acids.  The clover transfers organic nutrients to the bacteria in the nodule and the bacteria in turn provides amnio acids to the plant. Clover and its bacteria can add hundreds of pounds of nitrogen to an acre of soil during a season as a cover crop. 

Flowers of White Clover.
Ashe County, North Carolina.

Many of the species of Trifolium in the Southeast United States are native to Eurasia that have been become naturalized and now grow wild. Perhaps the most common clover in our area is White Clover (Trifolium repens).  This import from Europe is also called Dutch Clover and, of course, has white flowers.  The leaflets of this species often sport white, V-shaped marks.  

Red Clover (Trifolium pratense) in flower. 
Ashe County, North Carolina.

The flowers of Trifolium pratense, Red Clover, are not really red but rather a delicate pink.  Like White Clover, Red Clover leaflets can have V-shaped markings.  

Low Hop Clover (Trifolium dubium). 
Davidson County, North Carolina. 

Low Hop Clover, Trifolium dubium, is a low-growing clover with small yellow flowers.  This plant gets its name from the flowers that occur in heads that resemble the fruits of Hops (Humulus lupulus), an essential ingredient in beer. 

Rabbit Foot Clover (Trifolium arvense).
Rowan County, North Carolina. 

Rabbit Foot Clover (Trifolium arvense) has dense heads of rose-colored flowers.  The flowers have sepals that are tipped with long white hairs that give the plant a furry appearance and its name, Rabbit Foot.  Trifolium arvense thrives in dry, sandy soil, along roadsides and in what botanists call waste places.  

Crimson Clover.
Ashe County, North Carolina.  

Trifolium incarnatum, Crimson Clover, has the most stunning flowers of all the clovers in the Southeast.  They are bright crimson and are often found growing in large patches along highways and in meadows.   

A field of Crimson Clover.
Ashe County, North Carolina. 

All the clovers discussed so far were imported to North America, mostly to serve as cover crops or livestock feed.  There are two native clovers in North Carolina, both of which have limited ranges and small population sizes.  Carolina Clover (Trifolium carolinianum) is native to the Coastal Plain and is significantly rare.   Buffalo Clover (Trifolium stoloniferum) is an endangered species.  As its name suggests, Buffalo Clover was associated with eastern prairies and savannahs that were maintained by American Bison (Bison bison) herds. With the loss of these large herbivores in the east, the habitat for Buffalo Clover has diminished and it is now found in only a few locations.

Red Clover. 
Rowan County, North Carolina. 

Clovers come in a satisfying range of colors, shapes and sizes.  A meadow with clovers and abuzz with bees is a treat in springtime.  These humble plants fix nitrogen that reduces the need for fertilizer for crops.  Although most of the clovers we see in our area are introduced species, I am a fan. 

Panama insects

 

The beautiful Polymnia Tigerwing, Merchanitis polymnia.
Canopy Tower, Panama.

The exuberance of tropical diversity is on display in the insect world.  We went to Panama in June to see birds but insects kept drawing our attention.  Our travels took us to the Canopy Tower near the Panama Canal and to the Canopy Lodge in the mountains west of Panama City.  Panama has about 1000 different birds, but may have over 20,000 species of insects.  We tended to see the large and showy insects like butterflies, cicadas, and beetles, but many more were all around.

 An impressive Cicada (Zammara sp.) showed up in our room one day in the Canopy Tower.  This bright blue insect was about two inches long and its clear wings were marked with black.  Like the annual and periodical cicadas of North America, these tropical insects make loud buzzing calls from their perches in trees.  Cicadas feed on the sap of plants and are eaten by many species of birds.

Zammara sp, a brilliant blue Cicada.
Canopy Tower, Panama. 

 Another large insect that we found inside the Canopy Tower was a Peruvian Shield Mantis (Choeradodis rhombicollis).  This mantis was four inches long, bright green, with a shield covering the head and thorax, and large green wings over the abdomen.  The Peruvian Shield Mantis is camouflaged to look like the plant leaves on which it sits, waiting for prey.  The Mantis is a fierce predator that feeds on insects or even small lizards and hummingbirds.

Peruvian Shield Mantis (Choeradodis rhombicollis).
Canopy Tower, Panama. Photo by Diane Coggin.

Leaf cutter ants (Atta sp.) play a vital role in the ecology of tropical forests. Large colonies of these social insects send their workers into the forest.  These ants cut pieces of leaves from a variety of plants and return to the nest along cleared trails.  The ants use the plant material to grow a fungus, which is their real food, in underground chambers.  Humans and Leafcutter Ants are the most sophisticated farmers on earth. 

 

Leafcutter Ants (Atta sp.) foraging in the forest. 

Valle de Anton, Panama. Video by Diane Coggin

While hiking in rainforest one day, we saw a paper nest covered by blue wasps (Synoeca septentrionalis) on the trunk of a tree.  Synoeca septentrionalis belongs to a group called the Warrior Wasps because their sting is particularly painful. 

Warrior Wasps, Syneoca septentrionalis on nest. 
Valle de Anton, Panama. 

We also saw a number of beetles in the Panamanian forests.  A Flat-faced Longhorn Beetle Ptychodes taeniotoides was on the side of a bright yellow building above Valle de Anton.  The name longhorn refers to the very long antennae of beetles in this group.  

Flat-faced Longhorn Beetle (Ptychodes taeniotoides).
Valle de Anton, Panama.

Another beetle was walking the wire rail at the top of the Canopy Tower.  This beetle, Exophthalmus jekelianus is a weevil and uses its long snout to drink sap from leaves.  Exophthalmus jekelianus feeds on a variety of trees and is a major pest of shade-grown coffee.  The weevil we saw was innocent of this crime because no coffee is grown in this area.  

Exophthalmus jekelianus a small weevil.
Canopy Tower, Panama. 

The most impressive beetle we found was another weevil, Cholus cinctus. Its yellow body with black spots, large compound eyes and black snout made this weevil very striking.  The antennae of Cholus cinctus emerge halfway down the snout, giving it a slightly comical appearance.  This beetle was feeding on a ginger plant (Costus sp.) and is considered a pest by commercial growers of these showy flowers.    

Cholus cinctus, a large weevil, on Ginger (Costus sp).
Valle de Anton, Panama. 

The largest damselfly in the world was flying around the forest near the Canopy Tower.  Megaloprepus caerulatus has a wingspan of over seven inches.  The head sports two giant eyes, the thorax is black with green stripes and the abdomen is long and black.  But it is the wings that get your attention.  They are clear near the base with black bands near the end.  The males are larger than the females and they have white bands on the wings just inside the black bands.  These impressive insects fly slowly and the wing movement gives them their common name, Helicopter Damselflies.   

Megaloprepus caerulatus,
the largest damselfly in the world.
Canopy Tower, Panama. 

Butterflies were the most noticeable insects in Panama.  The skippers (Hesperiidae) are in a family of butterflies that have their greatest diversity in Central America.  We were lucky enough to see a number of skippers.  Two brightly colored skippers, called flashers, were feeding on Verbena planted outside the Canopy Tower. They are called flashers because their wings, heads and abdomens flash blue in flight.  The larger one was the Two-barred Flasher (Astraptes fulgerator) with two white bars on the wings.  The similar looking Astraptes egregious, the Small-spotted Flasher, had blue on the wings and body but lacked the white on the wings.  The Long-tailed Skipper (Urbanus proteus), which ranges from Argentina to Canada, was in Panama too.  This is a regular visitor to our North Carolina garden in summer so it was surprising to see this skipper among the tropical butterflies.  

A Two-barred Flasher, Astraptes fulgerator, feeding
one Verbena sp. 
Canopy Tower, Panama. 

Small-spotted Flasher (Astraptes egregious).
Canopy Tower, Panama. 

Long-tailed Skipper (Urbanus proteus). 
Valle de Anton, Panama. 

The Red Postman (Heliconius erato) is a striking butterfly with black wings, decorated with red and white bars.  This color pattern is a warning for predators, this butterfly is toxic.  The Red Postman is among a number of Heliconius species that exhibit Mullerian mimicry.  Mullerian mimics species are all toxic and resemble each other in color and pattern so all gain protection from predators. Another brightly colored butterfly that is common in Panama is Mechanitis polymnia, the Polymnia Tigerwing.  Its wings are black, yellow and orange.  It is also toxic and belongs to another group with Mullerian mimicry. 

Red Postman (Heliconius erato)
feeding on Lantana camaro.
Summit Ponds, Panama.

Polymnia Tigerwing on Hot Lips plant (Palicourea elata). 
Canopy Tower, Panama. 

Hades noctula is a beautiful little butterfly with black wings, an orange spot near the body and white stripes along the back edge of the wings.  It often perches on the underside of leaves.  Adelpha iphiclus is a butterfly with an interesting name, Pointed Sister.  It has brown wings with large white bars and yellow spots.  The genus name Adelpha is from the Greek meaning sister because the coloration of the butterfly resembles the habit of a Catholic nun. 

Hades noctula. 
Panama Rainforest Discovery Center, Panama. 

Pointed Sister (Adelpha iphiclus).
Panama Rainforest Discovery Center. Panama. 

The largest butterflies we saw were the Owl and Morpho butterflies.  The Dusky Owl Butterfly, Caligo illioneus is truly a giant, measuring over six inches long.  It is dark, mottled brown in color with large eyespots on the hind wings that bears a striking resemblance to the eyes of owls.  These spots may protect the butterfly because they resemble the eyes of a predator. 

Dusky Owl Butterfly (Caligo illioneus). 
Canopy Tower, Panama. 

The most spectacular butterfly we saw was the Menelaus Blue Morpho (Morpho menelaus).  The underside of the Morpho wings resemble those of the Owl Butterfly but the top of the wings flash electric blue.  Blue Morphos have a slow, flapping flight as they move through the forest seeking rotting fruit.  The iridescent blue color is structural, caused by the refraction of light from nanostructures in wing scales rather than blue pigments. As a Morpho flaps, its color can appear to change from black to blue depending on the angle of view.

Morpho menelaus, the Menelaus Blue Morpho. 
Pipeline Road, Panama. 

Menelaus Blue Morpho. Pipeline Road, Panama. Video by Diane Coggin 

The dazzling diversity of tropical insects we experienced stands in stark contrast with the well documented decline of insects populations around the world.  Forty percent of insects worldwide are declining and perhaps a third of insect species are endangered.  Insects provide a myriad of ecosystem services that range from pollination to waste recycling.  They are important links in many food chains and some parasitic insects control populations of agricultural pests.  So this is a salute to the insects, from the showy to the obscure.