They found that, compared with the cold barrenness of the Rongbuk valley north of Everest, the Kharta and, even more noticeably, the Kama valleys were warm and verdant. Rhododendron, and scrub birch and juniper cover the valley slopes and willow borders the lower streams. On a practical level they were well afforested with plenty of wood for fuel - at Rongbuk the only fuel had been yak dung.