Yesterday there were huge numbers of the Giant Mayfly (Hexagenia limbata) covering building surfaces facing the shoreline of Leech Lake in Walker Minnesota. The images below were taken on Walker’s public dock.
In the central image above, the Mayfly to the right is male and the one to the left is a female. Males typically are smaller, darker, and have larger eyes.
This species of Mayfly can be found throughout most of North America, but is most common in the Great Lakes region. There are several interesting facts about Mayflies.
Mayflies are one of the first insect species to evolve, appearing more than 300 million years ago.
As commonly known, they only live 1-2 days in their adult stage (imago), but can live up to two years in the nymph stage, and spend 2-3 days in a sub-adult stage (subimago).
The yearly emergence of Mayflies from nymph to subimago stages commonly happens over a very few days. This results in thick swarms of mayflies, so huge that the swarms can be mistaken for storms on weather radar.
Mayflies are a critical food source for fish in lakes and slow-moving streams, where they can comprise a significant proportion of the aquatic biomass.
Fly fishermen study the habits of Mayflies closely, in particular the Hexagenia, known by them as the “Hex”. Avid trout fishers flock to northern streams when the Hex emerges in late June and early July.
This is one more look at trees of SE Louisiana, where Magnolia and Mimosa trees bloom in the late spring. The next blog post will shift focus back to the lake country of Minnesota.
Southern magnolia (Magnolia grandiflora) are highly valued trees that are strongly associated with the southern United States. It is the state tree of Mississippi and the state flower of Louisiana.
The ancient genus Magnolia includes over 200 flowering plants. This genus was among the first flowering plants to evolve, around 95 million years ago. It is thought that the magnolia flower developed before bees were available as pollinators, which is likely why magnolias rely mainly on beetles for pollination.
The Magnolia genus is named for French botanist Pierre Magnol.
There are positive and negative aspects to the mimosa tree, also known as the Persian silk tree. As implied by the name, it is native to southwestern Asia.
In late spring and summer the beautiful pink flowers of the mimosa bloom with a pleasing scent attractive to butterflies, bees, and hummingbirds. It is also a fast-growing tree with a spreading form that effectively provides shade.
On the negative side, the tree is weak and short-lived. It is also messy when it drops its blooms, and later when it drops its large seed pods. It is not native to North America and is restricted in some areas as an invasive species.
This is a fragrant time of year in Louisiana. Two of our most sweetly scented flowers are blooming, Gardenia and Star Jasmine.
There are over 200 varieties of gardenia in a wide variety of sizes that are available for landscaping. As pictured above, we have several types thriving in our backyard. The scientific name for gardenia is Gardenia jasminoides; it is also called Cape Jasmine. However, it is actually in the family of coffee plants, Rubiaceae, while true jasmine is in the olive family, Oleaceae. Gardenia is native to SE Asia, and is now used worldwide in gardens in temperate to subtropical climates.
Trachelospermum jasminoides has several common names; Star Jasmine, Confederate Jasmine, Asiatic Jasmine and several others. However this plant is not truly jasmine either. It is in the family Apocynaceae, a family known as “dogbane” because several members in it are poisonous to dogs. In our area Star Jasmine vines are commonly used to climb over residential fences.
Eastern Band-Winged Hover Fly on Gardenia bloom
The “Insect ID” app identifies the insect on this gardenia bloom as a Eastern Band-winged hover Fly, Ocyptamus fascipennis. Hoverflies have mimicked the body shape of wasps and hornets, but are actually harmless. They are beneficial to garden plants because they feed on aphids and serve as pollinators.
Cherrybark oak (Quercus pagoda) is a large and valued Red Oak found in the southern United States. They commonly attain heights well over 100 feet and can have trunk diameters of up to five feet. I have an awesome specimen of this tree in my backyard in SE Louisiana — because of it, my backyard is perpetually shaded in summer.
Cherrybark oak in November (left) and February (right). It gradually sheds leaves from late November through January and already in February next year’s leaves are budding. Also appearing in late February and early March are the flowers of the oak, called catkins — they are small but evident in the picture from February shown above.
Here is a closer view of the flowers (catkins) of the Cherrybark Oak, fallen and draped over a camellia bush. In early March catkins drop from the oak, creating quite a mess and filling the air with oak pollen.
Cherrybark oak’s name reflects that its bark is similar to that of the black cherry tree. Its bark, along with a fallen leaf is shown above in the photo to the left (December). A new leaf in spring (March) is shown in the photo on the right. The scientific name of the tree is Quercus pagoda. The term “pagoda” was used because the shape of the leaf somewhat resembles the roof of a pagoda.
White blooms of the Cherokee Rose (Rosa laevigata) are a common sight along southeastern Louisiana roadways in early March. A native of southeast Asia, in the United States it is an invasive species. It has thrived in the southern US since its introduction here long ago (~1780), and was adopted as the state flower of Georgia in 1916.
Cherokee Rose climbs aggressively over other vegetation forming dense mounds of thorny canes. So, even though its springtime bloom is impressive, it is not always welcome in the landscape.
The name Cherokee Rose comes from its association with the Trail of Tears, the route taken by Cherokees and other native tribes when they were forcibly relocated to the west from the southeastern US.