MANILA, Philippines ? Thousands of rice farmers in northern Philippines are facing hardship and going further into debt after a typhoon mowed down stalks a week before harvest, officials said.

Swaths of rice farms were laid to waste or heavily flooded after typhoon Pepeng (international name: Parma) scythed through the farming provinces of Cagayan, Isabela, and Ilocos with hurricane-force winds and heavy rains.

"No amount of preparation would have prepared us for this," Cagayan province Governor Alvaro Antonio said, after Parma dumped nearly half a meter (20 inches) of rain across the rice bowl over the weekend.

Disaster officials and farmers in these areas described scenes in which large rice farms were turned into massive lakes and rice stalks with their nearly ripened grain blown down.

"The floodwaters started rising before dusk Sunday, one week before the rice harvest," David Ortal, 44, a farmer near the town of Batac in Ilocos, told AFP by telephone.

"The waters ebbed at dawn Monday, so the mature grains may be saved yet. However, the late plantings that had just flowered are likely lost."

The Cagayan Valley and Ilocos regions account for nearly 17 percent of the Philippines' total rice farming area, according to the statistics office.

Hundreds of thousands of farmers and their families depend on farming for their livelihood, with many in northern Philippines tenants or owners tilling small farms.

Aside from difficulties brought by the weather, they face challenges such as low un-husked rice prices versus expensive inputs like fertilizer and pesticides.

Poor irrigation, post-harvest facilities, and risks brought by pests and disease compound damage from the frequent storms that hit the country.

Typhoon damage in the past has only pushed farmers deeper into debt because they rely on money earned from selling their harvest to pay for the high input costs.

"We saw rice crops mowed down mercilessly by the winds. It's tragic because they are ready for harvest," said police Superintendent Salonga Abbugao, the operations and plans officer for Isabela.

He told AFP farmers would still try to salvage whatever they could from the crops. They were hoping for sunny weather in the next few days that would allow them to dry the harvested grains before they sprouted shoots or grew mold.

Pepeng?s devastation came just a week after tropical storm Ondoy (international name: Ketsana) triggered heavy rains further south on Luzon island, inundating large sections of Manila and surrounding areas.

Presidential spokesman Anthony Golez said initial damage to the farm sector wrought by the two storms stood at P5.5 billion ($117 million) and would certainly rise.

Golez said Agriculture Secretary Arthur Yap had assured that the country's food supplies would not be affected this year because there was enough buffer stock.

?(But the impact) could be felt by the first half of next year," he told reporters.

The Philippines relies heavily on imports to feed its rapidly growing population of 92 million.

In 2008, the country was forced to buy 2.3 million tons of rice despite record world prices at the time. President Gloria Macapagal-Arroyo announced on the weekend she had ordered more imports of the staple to head off a supply crunch.

However Roehlano Briones, a senior research fellow with the Philippine Institute for Development Studies, said he did not think the storms would lead to a sharp increase in rice prices in the medium term.

Other unaffected rice-producing regions, as well as the extra imports could, help the country meet demand, he told AFP.

Agriculture Secretary Yap also said the extra rain could help future harvests, as it filled up dams that would irrigate crops later.