Plants called ___________________ _ take up and retain unusually large amounts of heavy metals in
their above-ground parts.
Fill in the blank(s) with the appropriate word(s).
Question 2In northern states, the most common roadway ___________________ _, common salt (sodium
chloride), is used in huge amounts and creates saline or even sodic soil conditions that sometimes
reach toxic levels.
Fill in the blank(s) with the appropriate word(s).