The Colima Plant, scientifically Zanthoxylum fagara and sometimes Zanthoxylum clava-herculis, is a distinctive species known for its unique features and adaptability. These plants belong to the Rutaceae family, which also includes citrus, and are notable for their aromatic qualities and often thorny nature. While Zanthoxylum fagara is commonly called Wild Lime or Lime Prickly Ash, it also goes by regional names like Colima, Uña de Gato, and Corriosa. Zanthoxylum clava-herculis is known as Hercules’ Club or Toothache Tree. These species hold a significant presence in various ecosystems and have notable historical uses.
Identifying the Colima Plant
Zanthoxylum fagara typically grows as a large shrub or small tree, reaching heights of up to 10 meters (approximately 33 feet). Its branches are usually armed with hooked spines. Its leaves are oddly pinnately compound, meaning they have an odd number of leaflets, with 5 to 9 sessile, ovate to elliptic leaflets, each about 2 cm long. When crushed, they release a citrus scent.
Zanthoxylum clava-herculis grows as a small tree or large shrub, typically 15 to 30 feet tall, characterized by its spiny trunk and branches. The bark often develops distinctive spined, corky lumps or wart-like projections, giving it a gnarled, armored appearance. Both species produce small, inconspicuous flowers that range from greenish-yellow to white. These flowers are followed by small, spherical fruits, which mature into capsules containing shiny black seeds.
Native Habitat and Distribution
Zanthoxylum fagara is native to tropical and subtropical regions across the Americas. Its natural range includes southern Florida and Texas in the United States, extending through Mexico, Central America, the Caribbean, and as far south as Paraguay. It thrives in dry broadleaf evergreen shrublands and disturbed areas, often found in coastal hammocks and inland hammocks with calcareous soil influence.
Zanthoxylum clava-herculis is primarily distributed in the southeastern United States, from southern Virginia to mid-Florida, and west to Texas and Oklahoma. This species is often found in sandy soils along river banks, island bluffs, or dunes, and can also grow in maritime forests and shell middens.
Cultural and Ecological Significance
The Colima Plant, including Zanthoxylum fagara and Zanthoxylum clava-herculis, holds various cultural and ecological roles. Historically, the bark and leaves of these plants have been utilized in traditional medicine due to their numbing properties. Chewing on the bark or leaves can produce a tingling and numbing sensation, which led to their use as a remedy for toothaches, earning one of the species the common name “Toothache Tree”. Various parts of the plant, including the roots and fruits, have been used to create teas or tinctures for treating conditions such as fevers, rheumatism, dyspepsia, and poor circulation.
Beyond medicinal applications, the wood of Zanthoxylum fagara has been sought after for cabinetry and furniture making. The leaves and bark can also be crushed and used as a bitter-tasting spice, and the fruit of Zanthoxylum fagara offers a lemon zest flavor that initially tingles before numbing the mouth, similar to Szechuan pepper. Ecologically, these plants offer significant benefits to wildlife. They serve as a food source for birds, which consume their fruits, aiding in seed dispersal. They are also important host plants for the larvae of the Giant Swallowtail butterfly (Papilio cresphontes).
Growing the Colima Plant and Important Considerations
Cultivating the Colima Plant, especially Zanthoxylum fagara, can be a rewarding choice for gardeners seeking a hardy and unique specimen. These plants thrive in full sun to partial shade and require well-drained soil, though they can tolerate a range of soil types including acidic, alkaline, sandy, loamy, and clay. Once established, they exhibit high drought tolerance, meaning they do not require frequent watering; allowing the soil to dry out between waterings is beneficial. Regular watering is more important during prolonged dry periods.
A key consideration when handling the Colima Plant is its thorny nature. The sharp spines on its branches and trunk can cause painful punctures, so protective gear is advisable during pruning or other maintenance activities. Pruning can help maintain the plant’s shape and size, especially if grown as a shrub, and is best done in early spring before new growth emerges. These species are generally low-maintenance plants once established, with no serious insect or disease problems commonly reported. They can naturalize in suitable climates and may freely colonize through root suckers, forming dense thickets if left unchecked.