Tuesday, November 25, 2014

Chile Pequín

Chile pequín, Capsicum annuum
A native of southern North America, Central America, and parts of South America, Capsicum annuum has many common names including cayenne pepper, cherry pepper, and turkey pepper. Thanks to extensive cultivation and over fifty cultivars, other names linked to this species include paprika, red pepper, pimento pepper, sweet pepper, chili pepper, jalapeno, and poblano pepper. When referencing the wild progenitor, chile pequín or bird pepper are most often used. A deciduous shrub in the nightshade family, chile pequín is a perennial that will remain evergreen in warmer climates. It may grow up to 1 m (3 ft) and is most often found in thickets, groves, and ledges along rivers. The shrub tolerates shade, sun, and drought as well as loam, clay, limestone, and well drained sandy soils.

While the fruits are edible, the leaves contain toxic alkaloids.
Chile pequín has an extensive history with cultivation since 5000 B.C. It became more widespread when Columbus came to the New World and brought chile pequín back with him. Compared to many of the cultivars, chile pequín is noticeably more pungent. The spiciness is due to the presence of capsaicin which while odorless, colorless, and flavorless, irritates the mouth which in turn causes the brain to release endorphin; however, birds do not have the same reactions, but rather, no reaction. It is one reason they readily consume the fruits of chile pequín.

Note: There will be no post this Thursday. Have a happy Thanksgiving day!

Thursday, November 20, 2014

Copepods: Cyclops

A fresh water pond copepod, likely Cyclops spp.
Copepods are a subclass of the animal kingdom composed of tiny crustaceans. Of the Crustaceans, copepods are the largest and most diversified group with over 14,000 species identified. Although visible to the naked eye, they are often no larger than 2 mm in length, but a few species may reach 10 mm in length. Copepods can be found in ponds, marshes, streams, lakes, and coastal waters. Some species can tolerate more extreme habitats of hypersaline conditions, caves, and leaf litter.

Copepod bodies are composed of the cephalothorax and abdomen.
As the most numerous multi-cellular animal within the water community, copepods are very important ecologically. They, like many other plankton, are an important food source. Some species feed on mosquito larvae and have the potential to act as a malaria control mechanism. At the same time, some species are intermediate hosts to parasites including the guinea worm, tapeworms, and flukes.

As with other crustaceans, copepods are invertebrates with hard outer cells.
Cyclops is one genus of copepods named for the singular red or black eye. The eye is very simple, only able to detect light differentiation and not image detection. Rather than rely on the eye, the more complex antennae are the main sensory organs of plantonic copepods. They detect gravitational and inertial forces to help sense disturbances within the water generated by predators and prey. Their movements within the water are a characteristic jerking movement.

Thursday, November 13, 2014

Hackberry Gall Psyllid

Hackberry gall psyllid, Pachypsylla spp.
Hackberry gall psyllids, also known as hackberry nipplegall makers, hackberry blister gall psyllid, and jumping plant lice, are a 4-5 mm insect seen in autumn near hackberry trees. When the adults exit the galls during autumn, they search leaf litter, bark, and other crevices for a place to overwinter. In spring, they emerge to lay eggs on the new hackberry leaves. The nymphs feed on the leaves and cause the characteristic nipplegall for which the psyllids get one of their common names.

Hackberry gall psyllids often conjugate on window screens.
When the weather is warm, the adult psyllids swarm to houses, particularly on screens of windows and doors. Although a nuisance, they are not harmful to people, pets, or property. Control is difficult and not always recommended. Some parasitic wasps including Torymus pachpsyllae, Psyllaephagus pachypsyllae, and Eurytoma semivenae reportedly kill up to 51% of hackberry gall psyllids. As the wasps overwinter in galls on hackberry, it is not recommended to destroy the leaves of the tree. It should also be known that while hackberry gall psyllids can be numerous, the galls do not kill the host plant.

Thursday, November 6, 2014


Jimsonweed, Datura wrightii
Jimsonweed goes by a number of other common names including Jamestown weed, sacred thorn-apple, datura, sacred datura, moonflower, angel trumpet, devil's trumpet, stink weed, mad apple, Indian-apple, and tolguacha. There are several species found in North America, and in Texas, but they are all ill-scented, annual or perennial herbs within the nightshade family. The trumpet-shaped, crepuscular blooming flowers, often white or purplish, are large and showy, appearing between April and October. The spherical spiny seedpods split into four parts when they are ripe.

Ripe seedpod of Jimsonweed.
The less common name Jamestown weed comes from the mass poisoning of soldiers in Jamestown, Virginia during the Rebellion of Bacon in 1676. A salad prepared with boiled jimsonweed caused the soldiers to be overcome with the hallucinogenic properties of the herb. According to a written account of the event, the soldiers were confined after their comedic actions for their safety, and returned to normal after eleven days had passed. While the account of the incident focuses on the good-natured humor caused by the hallucinogenic effects of jimsonweed, death is a very possible outcome.

The spiky seedpods split in four when the seeds are mature.
Toxicity results from three main tropane alkaloids: atropine, scopolamine, and hyoscyamine. All parts of the plant are poisonous and can result in a rapid pulse, dilated pupils, restlessness, muscular twitching, weak pulse, irregular breathing, convulsions, coma, and death. While toxic to humans and livestock, it should be noted that a number of moth species, including sphinx moths, use the plant for both as a source of nectar and as a food source during their larval stage.

Tuesday, November 4, 2014

Texas Kidneywood

Texas Kidneywood, Eysenhardtia texana
Texas kidneywood is a native, deciduous, open shrub that reaches heights up to 3 m (10 ft). From April to October it blooms intermittently with spike white fragrant flowers. As a member of the legume family, Texas kidneywood has a pod-like fruit and compound leaves, but does not have thorns. The foliage in particular gives off a very pungent citrus smell. Although drought tolerant, extreme drought can cause defoliation. Texas kidneywood has been called an "ice cream" plant for deer due to it being highly palatable browse and highly nutritious. In addition to deer, various bees are known to be attracted to the flowers and the Dogface butterfly uses kidneywood as a host plant. Although kidneywood was once used in remedies for urological ailments, it is now mainly used in restoration projects, for nectar, and for dyes.