Despite the common names ringworm and dermatophyte, the disease is caused by a fungus, not a worm or plant. Trichophyton, Microsporum, and Epidermophyton are the most common genera that cause ringworm in humans. These organisms feed on keratin, the major structural component of hair, skin and nails.
Thuja occidentalis 'Nigra'. Naturally broad, pyramidal evergreen shrub displays deep green, scalelike needles arranged in flat sprays. New light green needles emerge in spring, deepening in color as they mature. Deep green color adds contrast to winter landscape.
'Nigra', also known as 'Dark American', is a popular selection that keeps its deep green color all winter long; it grows 10-20 feet tall and 4-6 feet wide at maturity. 'Smaragd', also called 'Emerald Green', is finer textured and slower growing, reaching 10-15 feet tall and 3-4 feet wide.