A local official here claimed that no less than 80 houses have been buried beneath the limestone and soil erosion affecting sitios Ilaud and Balikbayan.
He said some 600 residents left homeless by the continuous landslides have been evacuated to safer grounds.
"The worst fear happens during night time when soil movement is faster and stronger," according to Mayana barangay chairman Alberto Aleria.
Aleria claimed that even the improvised paths they have constructed simply disappear within 48 hours because of the erratic movement of the soil underneath.
Dionisio Sibidon, a 48-year-old farmer who was forced to evacuate with his family because of the landslides, said they have to repeatedly move out because the soil is constantly shifting, making it difficult for them to build even a temporary shelter.
He said other evacuees, left homeless by the landslides, have been deprived of their livelihood because of the damage to their farmlands.
Barangay Mayana, considered the highest point in the province, is known for its banana plantations. Its products are primarily exported to Japan.
The barangay also produces cut flowers, vegetables and lanzones.
Jagna Mayor Exuperio Lloren said the abundant water supply in the area, ironically, was among the factors that caused the shifting of the soil.
Lloren pointed out the water pipes of the rural waterworks system in the barangay still overflow to roadside canals even after they were cut by the landslide.
The highway from Jagna town proper to Mayana is not passable, Lloren said.
Going to Mayana requires passing through Sierra-Bullones town, but motorists taking this route cannot reach Jagna town because of the soil erosion and felled trees blocking the highway, he said.
Lloren said he has already constructed an evacuation center for the landslide victims, located in front of the elementary school.