Corn (Zea rnays L.) and other crops can utilize both
ammonium-nitrog(eNn H4-N)a nd nitrate-nitrogen (NO3-N),
andn umerousstu dies havei ndicatedt hat cornf requentlyg rows
better when supplied a mixture of both NO3 and NH~ than
whens upplied exclusively NO~.H owevert,h ese observations
were considered to be of limited practical value because NO~
has historically beent he predominaNnt f orma vailable to corn
due to rapidn itrification of NH~to NO3 in mosta gricultural
soils. Witht he advenot f nitrificationi nhibitors,i t is nowp ossible
to supplys ignificant levels of NH4 as well as NO3T. his
article reviewst he past as well as currentr esearchr elated to
response of corn to NH4-N.