Finish the following sentences.
1) Proper application of irrigation water requires …
2) A farmer must know when … and how much …
3) Plants need irrigation only after they have used up most of …
4) There are four general methods of applying irrigation water …
5) In surface irrigation, the farmer runs water over …
6) Two chief types of surface irrigation are … and …
7) Small soil walls called … hold the water on the field.
8) The dikes divide the field into …
9) Flood irrigation works best on … or … terrain where water is plentiful.
10) Most crops that are planted in rows are irrigated by water from …
11) The farmer plants seeds in the … between the furrows.
12) Sprinkler irrigation provides water through pipes that …
13) A pump forces water through a pipe to …
14) The sprinkler heads distribute water to the crops in …
15) … have an engine and wheels built into the sprinkler unit.
16) These systems move across a farm under …
17) Trickle irrigation, also called drip irrigation, furnishes water through … that lie …
18) As water flows through …, it trickles out of … into the soil.
19) Only the soil directly around the plants receives …
20) Subirrigation applies water from beneath the …
21) The water comes from … or …, and the surface of the ground remains …
Answer the following questions.
1) What factors must a farmer consider before irrigating?
2) What are general methods of applying irrigation water?
3) What are the two types of surface irrigation?
4) Flood irrigation covers the entire surface of a field with water, which soaks into the soil, doesn’t it?
5) What holds the water on the field?
6) Where does flood irrigation work best?
7) In which method are rows of furrows dug across a field?
8) Does the farmer plant seeds in the ridges between the furrows?
9) What irrigation provides water through pipes that lie on or are mounted above the ground?
10) What irrigation is also called drip irrigation?
11) Why is trickle irrigation used only for high-value crops, such as fruits and vegetables?
12) Where does subirrigation apply water from?
13) Does the surface of the ground remain dry in subirrigation?
14) Why does the surface of the ground remain dry in subirrigation?
15) What method of irrigation is used in our country?