Dendrosenecio adnivalis

Dendrosenecio adnivalis is a species of giant groundsel found in the mountains of Eastern Africa. It grows on the Rwenzori Mountains and Virunga Mountains in Uganda and the Democratic Republic of the Congo.

Description
Dendrosenecio adnivalis can reach heights from 3 to 11 feet (6 to 10 meters) tall. The trunk can be 40 centimeters in diameter with the pith being 1 to 2 inches (3 to 4 centimeters) in diameter. The stems have 25 to 60 leaves arranged in a dense rosette shape at the top. The old leaves are persistent, with withered leaf-bases covering the stalk for 1 to 3 meters below the leaf rosettes. The surfaces of the leaves are either elliptic or heart-shaped, and can reach 40 inches (96 centimeters) long and 11 inches (26 centimeters) wide, being hairy on the top, and with little or no hair on the bottom. The flowers are borne in clusters reaching 68 inches (160 centimeters) tall, and 25 inches (60 centimeters) wide. The heads of the flowers have 9 to 20 ray florets, reaching 16 millimeters long, or with no ray florets at all, and 90 to 250 disc florets.

Distribution
The Congo Basin is very wet, due to the humid air which is trapped by the mountains, and that rain falls on most days, including those in dryer months. Above 8200 ft (2500 meters), clouds can persist for several days, making the Rwenzori and the Virunga a wetter environment than most mountains found in East Africa. Dendrosenecio adnivalis lives at altitudes of 9800 to 12,000 feet (3000 to 3800 meters) on the Rwenzori Range, along with another giant groundsel, Dendrosenecio johnstonii, which is less common on wetter soils than Dendrosenecio adnivalis.

On the Virunga Mountains, groves of Dendrosenecio adnivalis grow after tree heaths of the Erica genus in clearings with Lobelia wollastonii, until reaching about 14,000 feet (4300 meters), where vegetation is sparse.

Synonyms
Most herbariums that contain specimens of Dendrosenecio adnivalis file them under the name, Senecio johnstonii.


 * Senecio adnivalis Stapf
 * Senecio erioneuron Cotton
 * Senecio refractisquamatus De Wild.