Soil science

Question 1 of 10

Nitrogen deficiency in plants shows as

Question 2 of 10

The soil with the smallest particles is

Question 3 of 10

A soil sample weighing 120 g wet and 100 g oven-dry has a moisture content (dry basis) of

Question 4 of 10

The soil with the largest particles is

Question 5 of 10

Soil air is important because roots need

Question 6 of 10

Which of the following is an organic manure?

Question 7 of 10

Earthworms improve soil mainly by

Question 8 of 10

Yellowing of older leaves (chlorosis) in maize is usually a sign of lack of

Question 9 of 10

The horizon of a soil profile richest in humus is the

Question 10 of 10

The three primary (major) plant nutrients are