Pumpkins (南瓜) have all shapes and sizes and have colors of golden orange, white and green. Cooked in a pie, they are symbols of autumn that are grown in every county of Washington.

U.S. farmers grow more than a billion pounds of pumpkins every year, and many farmers use sheets (膜) of plastic blocking the grass and preventing water loss to make their plants grow well. In the country, farmers use about a billion pounds of plastic every year. Unfortunately, that plastic is thrown away finally, and in some areas, burned in the fields.

For several years, Carol Miles has studied a new product—the soil-biodegradable (土壤生物降解的) plastic cover that can be left in the ground after harvest, then broken down by things in the soil. “You don't need to pull it out of the field and throw it away every autumn, saving time and money,” Miles said.

Most pumpkins grow along vines (藤蔓) that spread through the grass-blocking cover, and Miles wanted to see how pumpkin fruit performed over the plastic cover. That brought a challenge: the soil-biodegradable cover stuck to the bottom of the fruit.

“We have a lot of dew (露水) in the morning, and we found that if we let the fruit dry after harvest, the cover would stick more strongly to the pumpkins,” Miles said. “Nobody wants plastic stuck to pumpkins, even if it's biodegradable. But if you wipe the fruit before the dew dries, the plastic comes right off.”

Farmers who grow plants that don't set fruit on plastic covers won't meet this challenge. For those who do, it means an extra step that they'll have to weigh against advantages and disadvantages for the development.

“Challenges aside, working with this crop can bring on a happy picture,” the farmer Tymon said. “Pumpkins are great. They have bright colors, and are really fun to work with.”

【小题1】How did farmers deal with the sheets of plastic in old farming method?

A．They collected them and recycled them.

B．They burned them or threw them away.

C．They covered them under the ground.

D．They broke down them and buried them in the soil.

【小题2】What's the advantage of Mile's new product?

A．It prevents water loss.

B．It blocks the grass.

C．It is stuck to pumpkins easily.

D．It's environment-friendly.

【小题3】How can farmers do to prevent the plastic sticking to pumpkins?

A．Let the pumpkins break down plastic sheets.

B．Wipe the dew from the plastic cover.

C．Clean the pumpkins when they're wet.

D．Put some powder on the plastic sheets.

【小题4】What does the underlined words “weigh against” means?

A．Balance against.	B．Fight against.
C．Remove.	D．Measure.