Thursday, January 29, 2015

Sacred Bamboo

Sacred Bamboo, Nandina domestica
Sacred bamboo, Nandina domestica, is sometimes also known as heavenly bamboo or simply as nandina. It is a semi-evergreen woody shrub that can reach 2.5 m (8 ft) in height. While visually similar to bamboo, sacred bamboo is within the family Berberidaceae rather than the grass family Poaceae like bamboo. It blooms white flowers which become red berries that persist until consumed. It tolerates drought and shade, but this non-native shrub, introduced from Asia in the early 1800s, has become very invasive in many southern states including Texas and Florida.

Tuesday, January 27, 2015

Fragrant Honeysuckle

Fragrant Honeysuckle, Lonicera fragrantissima
Fragrant honeysuckle is a deciduous shrub that can grow up to 3 m (10 ft) in height. It can grow in either full sun or part shade and adapts to a wide range of soils. As early as January, it blooms very fragrant white flowers and is sometimes considered a harbinger of spring. Fragrant honeysuckle is resistant to both drought and deer; however, it can also become very invasive.

Blooming branch of fragrant honeysuckle.
Sweet breath of Spring, Winter honeysuckle, and Standing honeysuckle are other names for Lonicera fragrantissima, but it is not native to North America. It originates from eastern Asia and was first introduced in the late 1800s as an ornamental plant not long after it was introduced in Europe. Fragrant honeysuckle was often planted near frequently-used gates for its high fragrance and hardy character.

Fragrant honeysuckle is a dense shrub, not a vine like other honeysuckles.
Unfortunately, fragrant honeysuckle spreads rapidly by seeds favored by birds even though they are not a high-fat, nutrient-rich food needed for migration. In addition, fragrant honeysuckle provides dense cover which, while useful for wildlife, crowds out native plant species and alters soil chemistry. The native coral honeysuckle is one recommended alternative to winter honeysuckle.

Thursday, January 22, 2015

Mistletoe

Mistletoe, Phoradendron spp.
Mistletoe are dioecious, parasitic plants within the order Santalales and can be found on almost all continents of the world. The berries of the female plant are small and white and a favorite of many species of birds. They have a sticky aspect to them that allows the seeds to remain attached to any branch on which they land. When the seed germinates, it grows through the bark of the tree. Rootlike structures called haustoria develop in the water-conducting tissue of the tree and gradually extend up and down the branch. An old, mature mistletoe may be several feet in diameter and cause large swollen areas to develop on the tree branch where it has affixed itself.

Another angle of the mistletoe infestation.
Many species of trees, from cottonwoods and oaks to maples and conifers, can be attacked by the broad range of mistletoe. A healthy tree can tolerate a few mistletoe branch infections, but a heavily infested tree can be killed. A tree may be saved by removing as many infected branches as possible. If allowed to grow for too long, though, the mistletoe may have established itself enough to return.

A more in-depth post on Mistletoe can be found on my Google+ post here written a month ago.

Tuesday, January 20, 2015

Hiatus

At the very least, here is a photograph for today from one of my hikes.
It has been busy so there will be no post for today, but I will have one ready for this Thursday!

Thursday, January 15, 2015

Agarita

Agarita, Mahonia trifoliolata (Berberis trifoliolata)
Also known as Agarito, Agarita is an evergreen shrub with grey-green, trifoliated, holly-like leaves. The three sharp pointed leaflets join at a central point which helps distinguish it from the similar Texas mahonia, M. swaseyi and red barberry, M. haematocarpa. Agarita can be found throughout most of Texas, New Mexico and Arizona, and into Mexico. It can grow up to 1.8 m (6 ft), is drought and heat tolerant, and prefers full sun, but can grow in partial shade. In many desert shrub and grassland communities, agarita is dominant or codominant. In addition to providing as valuable cover for many species of wildlife, it also provides as a source of food. The fragrant yellow flowers that bloom in February and March are followed by red berries from May to July that are a favorite of songbirds, small mammals, and humans.

Tuesday, January 13, 2015

Frostweed

Frost flower on Frostweed, Verbesina virginica
A shade loving biennial, Verbesina virginica can be found in portions of the southern United States. It has dark green leaves with white autumn flowers and can grow up to 1.8 m (6 ft) tall. It is a favorite nectar plant of many bees and butterflies, including migrating monarchs and has past use as tobacco by some Native American tribes. There are many common names for this plant including white crownbeard and Indian tobacco, but it’s mostly known as frostweed.

A shade loving plant that does well around oak trees.
As it is, Verbesina virginica is not the only plant known as frostweed. Others share this common name including Helianthemum canadense and H. bicknellii for the reason that when temperatures get cold enough, the stems exude water which forms beautiful ice crystal formations. These formations have many names: frost flowers, ice ribbons, frost castles, crystallofolia, and rabbit butter; but the process itself is known as ice segregation.

It is not the full stem that splits, but rather the epidermis of the stem.
Ice segregation is when cold water moves through a medium towards the presence of ice, freezes at the interface, and adds to the ice structure. For a frost flower to form, the air temperature must be below freezing, but the moisture in the stem must remain liquid. The ground must also be warm enough for the roots to be active in moist soil. Water in the stem is drawn upward, expands as it starts to freeze, and results in a vertical split on the stem, specifically in the epidermis. As more water is drawn from the ground, the thin ice layer exudes further to form beautiful and interesting shapes.

Each frost flower is unique and different for each plant and season.
While frost flowers are the most common instance of ice segregation, it is not limited to the stems of plants. Similar phenomena occur in loose soils forming ice needles, also known as kammeis or pipkrake, as well as dead tree branches forming hair ice, also known as haareis, silk frost, or cotton candy frost, and also on rocks forming pebble ice.

Different location from above with frostweed growth and frost flowers.
In addition to Verbesina virginica, Helianthemum canadense and H. bicknellii, the phenomenon of frost flowers has also been reported for Cunila origanoides, Pluchea odorata, P. foetida, and P. camphorata, as well as on the lower stems of some species of Lamiaceae, Verbenaceae, and Apocynaceae. The key to all species confirmed to form frost flowers is that they are herbaceous and perennial, and thus they maintain a root system that overwinters.

Splitting stems of frostweed surrounded by new and old Turk's Cap growth.
The adaptive role of frost flowers is still speculative, especially considering that it occurs in many different species. Plants that adapt to live in a freezing climate have three options for survival: die and leave seeds, remain active, or become dormant. While annual herbaceous species most often follow the first option, long-lived woody species often follow one of the other two. For the plants that exhibit frost flowers, they don’t seem to fit either category nicely. For now, the best guess, provided by Dr. Bob Harms who coined the term crystallofolia, the phenomenon is an adaptive self-pruning. It is possible that frost flowers allow for a head start on spring growth, but as it is, it is simply a best guess for now.


The original post on frost flowers can be found on Google+ here with different photos than the ones shown here, but with the same text that has been provided above.

Thursday, January 8, 2015

Inland Sea Oats

Inland Sea Oats, Chasmanthium latifolium
Inland Sea Oats is a clump forming perennial grass which grows up to 1.2 m (4 ft) in height. It can be found throughout eastern and central North America. The oat-like seed heads start of green, but gradually turn from an ivory to a brown within a few months before dropping off. With its easy reseeding, dislike for intense sunlight, and tolerance of salt, it is the plant often used for critically eroding shaded areas. Some birds and mammals use the seeds as a source of food, and it is a host plant for a few species of butterflies including skippers. Inland Sea Oats are a popular addition to cut and dried arrangements.

Tuesday, January 6, 2015

Texabama Croton

Texabama Croton, Croton alabamensis var. texensis
A variety of Alabama croton, a semi-evergreen shrub once thought to be endemic to only three counties in Alabama and Tennessee, Texabama croton was discovered in 1989 in three Texas counties. The main difference between the variations are the pigmentation of the scales. With preference for limestone and loamy clay soils, and rocky slopes, Texabama croton is found in Central Texas canyons. It can grow between 1.8 to 3.7 m (6 to 12 ft) in part shade. Texabama croton blooms yellow flowers as early as February and as late as October. In autumn, the foliage turns a bright orange with a copper scaling on the lower surface.