Singletary Pea (Lathyrus hirsutus), also known as Caley pea, hairy vetchling, and rough pea, is an annual legume native to Europe, North Africa, and much of Asia. It has naturalized in other continents, including North America, completing its life cycle within a single growing season.
Identifying Singletary Pea
Singletary Pea is an herbaceous annual that exhibits a vining, sprawling, and climbing growth habit, often utilizing tendrils to cling to nearby vegetation for support. Its stems are winged, flattened, and generally hairless, branching occasionally as the plant matures.
The compound leaves consist of two long, narrow leaflets, typically up to 3.5 inches long, which terminate in a branched, coiling tendril. At the base of each compound leaf, a pair of lanceolate stipules can be observed.
The plant produces small, pea-like flowers, measuring up to 0.5 inches across, which emerge from leaf axils, usually one or two per inflorescence. These flowers can display a range of colors including pink, blue, purple, or white, with blooming occurring from late spring to summer.
Following flowering, oblong, flat-sided seed pods develop, covered with hairs from minute bulbous bases. These pods, typically 1 to 1.5 inches long, transition from green to brown as they mature and contain four to ten mottled, round, and flattened seeds.
The plant’s root system includes a taproot. It often forms nodules, a characteristic of legumes.
Agricultural Benefits and Applications
Singletary Pea offers several advantages when integrated into agricultural systems, particularly as a cover crop. Its primary benefit stems from its ability to fix atmospheric nitrogen into the soil through a symbiotic relationship with rhizobacteria in its root nodules. This nitrogen enrichment improves soil fertility, reducing the need for synthetic nitrogen fertilizers.
The dense growth of Singletary Pea also aids in soil erosion control. It provides ground cover, which prevents runoff and allows water to infiltrate the soil more effectively.
As a cover crop, it contributes to increased soil organic matter content, enhancing soil structure and overall health. Its vigorous growth also suppresses weeds by competing for light, water, and nutrients, reducing weed populations during its growth phase and subsequent cash crop seasons.
Beyond its role in soil health, Singletary Pea can serve as a valuable forage crop for livestock and wildlife. Its vegetation is nutritious, providing protein and other essential nutrients for animals. When properly managed, it can offer a high-yielding, palatable feed source. Singletary Pea is also utilized in wildlife food plots, attracting and providing sustenance for various species, including white-tailed deer and certain bird species like quail.
Cultivation and Management Practices
Singletary Pea thrives in full to partial sunlight and well-drained loamy soils, preferring a slightly acidic to neutral pH (5.8-7.5). It is sensitive to waterlogged conditions, so good drainage is important. Incorporating compost or well-rotted manure before planting can improve soil texture and fertility.
Planting occurs in fall or early spring, as Singletary Pea is a cool-season annual. Direct sowing is recommended due to the plant’s sensitivity to root disturbance. Seeds should be planted 0.5 to 1 inch deep. Seeding rates are typically 75-85 plants per square meter, or 80-100 pounds of pure live seed per acre for broadcasting. For rows, space 18-24 inches apart.
Singletary Pea requires moderate water, watering when the soil partially dries out. While resistant to many pests and diseases, it can face issues like root knot nematodes, anthracnose, dodder, scab, powdery mildew, and seedling diseases. Crop rotation and proper soil drainage help mitigate these problems. For cover crops, termination is by mowing or tillage. For forage, graze before blooming or seed production to prevent toxicity.
Important Considerations and Potential Challenges
Despite its agricultural benefits, Singletary Pea contains neurotoxins in its seeds, specifically BOAA (or ODAP). This can cause lathyrism, a neurological condition leading to irreversible neurological damage, especially in livestock. Horses are particularly sensitive, showing incoordination and hind leg paralysis, known as stringhalt.
Cattle, chickens, and swine are also susceptible, with chronic consumption potentially causing skeletal deformities in growing animals and birth defects in calves. Though less common in humans, lathyrism can manifest as spastic paraparesis if large quantities of seeds are consumed over extended periods. Caution is important when using Singletary Pea as forage.
Safe grazing practices are important. Remove animals from pastures with mature Singletary Pea, especially when seeds are present. Grazing should occur before blooming or seed production to minimize toxin exposure. Hay with intact seed pods should never be fed to horses or other susceptible animals. Avoid relying on Singletary Pea as a sole forage source; this is an important management strategy.
Furthermore, Singletary Pea can escape cultivation and become a weedy species in disturbed areas like roadsides, pastures, and field edges. Mechanical control, such as mowing, or careful herbicide application may be necessary to manage its spread.